/***********************************************************************/        /***********************************************************************/
/* FreeVR OpenGL tutorial example 14a: ex14a_button.c                  */        /* FreeVR OpenGL tutorial example 14b: ex14b_slider.c                  */
/* Last tested with: FreeVR version 0.6a                               */        /* Last tested with: FreeVR version 0.6a                               */
/* Last Modified: January 11, 2007                                     */        /* Last Modified: January 11, 2007                                     */
/* URL: http://freevr.org                                              */        /* URL: http://freevr.org                                              */
/***********************************************************************/        /***********************************************************************/
/* This example code demonstrates a VR application program that        */        /* This example code demonstrates a VR application program that        */
/*   allows the user to use special objects in the virtual world.      */        /*   allows the user to use special objects in the virtual world.      */
/*   Because these objects can be used to control the functionality    */        /*   Because these objects can be used to control the functionality    */
/*   of the virtual world, they are refered to as "virtual controls".  */        /*   of the virtual world, they are refered to as "virtual controls".  */
/*   Specifically, in this example toggle-button virtual control is    */        /*   Specifically, in this example a slider virtual control is         */
/*   introduced.  The button is toggled by touching it with the wand.  */        /*   introduced.  The slider platter can be grabbed and slid, or       */
                                                                                 /*   clicking on the vertical bar will cause the slider to jump to     */
                                                                                 /*   that value.                                                       */
/*                                                                     */        /*                                                                     */
/*                                                                     */        /*                                                                     */
/* The new features of this example include:                           */        /* The new features of this example include:                           */
/*   - the use of the expanded wrs_shapes.c file.                      */        /*   - nothing new provided by the library.                            */
/*                                                                     */        /*                                                                     */
/* Considerations:                                                     */        /* Considerations:                                                     */
/*   Intersection testing with an object must be done it its space     */        /*   - Should the slider always move with the wand or just with button?*/
/*     (ie. UI objects in rw space, and virtual objects in vw space    */        /*   - How do the user interface objects affect the virtual world?     */
/*   Actions from contacted object are specific to the object type.    */     
/*   Don't forget to read/write lock all references to 'wd'.           */     
/*   How does the user interface object affect the virtual world?      */     
/*                                                                     */        /*                                                                     */
/* This application uses the files:                                    */        /* This application uses the files:                                    */
/*   - wrs_shapes.c  (Bill Sherman's simple OpenGL shapes)             */        /*   - wrs_shapes.c  (Bill Sherman's simple OpenGL shapes)             */
/*                                                                     */        /*                                                                     */
/* Copyright 2010, William R. Sherman, All Rights Reserved.            */        /* Copyright 2010, William R. Sherman, All Rights Reserved.            */
/*   In particular, the right to republish this file in whole or in    */        /*   In particular, the right to republish this file in whole or in    */
/*   part, in any form (including electronic forms) is prohibited      */        /*   part, in any form (including electronic forms) is prohibited      */
/*   without written consent of the copyright holder.                  */        /*   without written consent of the copyright holder.                  */
/***********************************************************************/        /***********************************************************************/
#include <stdio.h>      /* needed for printf(), etc. */                          #include <stdio.h>      /* needed for printf(), etc. */
#include <stdlib.h>     /* needed for exit() & getenv() */                       #include <stdlib.h>     /* needed for exit() & getenv() */
#include <signal.h>     /* needed for signal() and its arguments */              #include <signal.h>     /* needed for signal() and its arguments */
#include <unistd.h>     /* not sure why/whether this is needed */                #include <unistd.h>     /* not sure why/whether this is needed */
#include <math.h>       /* needed for fabs() */                                  #include <math.h>       /* needed for fabs() */
 
#include <GL/gl.h>      /* needed for all OpenGL functions & values */           #include <GL/gl.h>      /* needed for all OpenGL functions & values */
 
#include "freevr.h"     /* needed for FreeVR functions & values */               #include "freevr.h"     /* needed for FreeVR functions & values */
#define WAND_SENSOR     1       /* TODO: this should really be based on the c    #define WAND_SENSOR     1       /* TODO: this should really be based on the c
 
/* Define some values to adjust the compilation of this example */               /* Define some values to adjust the compilation of this example */
#define DRAW_UITEXT                                                              #define DRAW_UITEXT
#define USE_SOCKETS                                                              #define USE_SOCKETS
#define MAX_OBJECTS     1000                                                     #define MAX_OBJECTS     1000
                                                                                 #define SLIDER_LENGTH     3.0
 
 
/* Define a structure for information about each individual object. */           /* Define a structure for information about each individual object. */
typedef struct {                                                                 typedef struct {
                float                   x, y, z;                /* location o                    float                   x, y, z;                /* location o
                float                   size;                   /* size of th                    float                   size;                   /* size of th
                GLubyte                 color[3];               /* color of t                    GLubyte                 color[3];               /* color of t
                enum {  cube,                                                                    enum {  cube,
                        sphere,                                                                          sphere,
                        pyramid,                                                                         pyramid,
                        ud_pyramid }    shape;                  /* shape of t                            ud_pyramid }    shape;                  /* shape of t
                enum {  vw_normal,                                                               enum {  vw_normal,
                        ui_button }     type;                   /* type of th                            ui_button,
                                                                                                         ui_slider }     type;                   /* type of th
                int                     ui_button_value;        /* button val                    int                     ui_button_value;        /* button val
                                                                                                 float                   ui_slider_value;        /* slider val
        } ObjectType;                                                                    } ObjectType;
 
/* Define a structure for holding a database of the virtual world. */            /* Define a structure for holding a database of the virtual world. */
typedef struct {                                                                 typedef struct {
                int             quit_bit;                       /* a flag to                     int             quit_bit;                       /* a flag to 
                int             number_of_objects;              /* number of                     int             number_of_objects;              /* number of 
                int             contacted_object;               /* object con                    int             contacted_object;               /* object con
                int             last_contacted_object;          /* object pre                    int             last_contacted_object;          /* object pre
                ObjectType      object[MAX_OBJECTS];            /* array of o                    ObjectType      object[MAX_OBJECTS];            /* array of o
                vrLock          lock;                           /* to avoid b                    vrLock          lock;                           /* to avoid b
        } WorldDataType;                                                                 } WorldDataType;
 
 
/****************************************************************************    /****************************************************************************
/* These function declarations are very important -- they will be used as arg    /* These function declarations are very important -- they will be used as arg
void    exit_application(int signal);           /* cleanly close down operati    void    exit_application(int signal);           /* cleanly close down operati
 
void    init_gfx();                             /* initialize the graphics       void    init_gfx();                             /* initialize the graphics   
void    draw_world(WorldDataType *wd, vrRenderInfo *rendinfo); /* render the     void    draw_world(WorldDataType *wd, vrRenderInfo *rendinfo); /* render the 
void    init_world(WorldDataType *wd);          /* initialize the world param    void    init_world(WorldDataType *wd);          /* initialize the world param
void    update_world(WorldDataType *wd);        /* perform the world simulati    void    update_world(WorldDataType *wd);        /* perform the world simulati
 
void    end_world();                            /* close down the world opera    void    end_world();                            /* close down the world opera
void    init_objects(WorldDataType *wd);        /* initalize the objects in t    void    init_objects(WorldDataType *wd);        /* initalize the objects in t
 
 
/***********************************************************************/        /***********************************************************************/
main(int argc, char* argv[])                                                     main(int argc, char* argv[])
{                                                                                {
        WorldDataType   *wd;                                                             WorldDataType   *wd;
 
        /**********************************/                                             /**********************************/
        /*** initialize FreeVR routines ***/                                             /*** initialize FreeVR routines ***/
        /**********************************/                                             /**********************************/
        signal(SIGINT, SIG_IGN);                                                         signal(SIGINT, SIG_IGN);
        vrConfigure(&argc, argv, NULL);         /* allow CLAs to affect confi            vrConfigure(&argc, argv, NULL);         /* allow CLAs to affect confi
        vrStart();                                                                       vrStart();
        signal(SIGINT, exit_application);                                                signal(SIGINT, exit_application);
 
        /********************/                                                           /********************/
        /* create the world */                                                           /* create the world */
        wd = (WorldDataType *)vrShmemAlloc0(sizeof(WorldDataType));                      wd = (WorldDataType *)vrShmemAlloc0(sizeof(WorldDataType));
        wd->lock = vrLockCreate();                                                       wd->lock = vrLockCreate();
        init_world(wd);                                                                  init_world(wd);
 
        /***************************************/                                        /***************************************/
        /* set up the FreeVR library functions */                                        /* set up the FreeVR library functions */
        vrFunctionSetCallback(VRFUNC_DISPLAY_INIT, vrCallbackCreate(init_gfx,            vrFunctionSetCallback(VRFUNC_DISPLAY_INIT, vrCallbackCreate(init_gfx,
        vrFunctionSetCallback(VRFUNC_DISPLAY, vrCallbackCreate(draw_world, 1,            vrFunctionSetCallback(VRFUNC_DISPLAY, vrCallbackCreate(draw_world, 1,
 
        /********************************************************/                       /********************************************************/
        /* define the application name, authors, controls, etc. */                       /* define the application name, authors, controls, etc. */
        vrSystemSetName("example 14a -- button widget");                                 vrSystemSetName("example 14b -- slider widget");
        vrSystemSetAuthors("Bill Sherman");                                              vrSystemSetAuthors("Bill Sherman");
        vrSystemSetExtraInfo("An example to demonstrate a button virtual cont            vrSystemSetExtraInfo("An example to demonstrate a slider virtual cont
        vrSystemSetStatusDescription("Application running fine");                        vrSystemSetStatusDescription("Application running fine");
        vrInputSet2switchDescription(0, "Terminate the application");                    vrInputSet2switchDescription(0, "Terminate the application");
        vrInputSet2switchDescription(1, "Move the selected object");                     vrInputSet2switchDescription(1, "Move the selected object");
        vrInputSet2switchDescription(3, "Reset the travel matrix (take us hom            vrInputSet2switchDescription(3, "Reset the travel matrix (take us hom
        vrInputSetValuatorDescription(0, "Rotate us in the world about the Y-            vrInputSetValuatorDescription(0, "Rotate us in the world about the Y-
        vrInputSetValuatorDescription(1, "Move us though the world in the dir            vrInputSetValuatorDescription(1, "Move us though the world in the dir
        vrInputSet6sensorDescription(WAND_SENSOR, "Move a short cyan pointer             vrInputSet6sensorDescription(WAND_SENSOR, "Move a short cyan pointer 
 
        /***************************/                                                    /***************************/
        /*** do world simulation ***/                                                    /*** do world simulation ***/
        /***************************/                                                    /***************************/
        vrUserTravelReset(VR_ALLUSERS);                                                  vrUserTravelReset(VR_ALLUSERS);
        /* run until the user has indicated it's time not to */                          /* run until the user has indicated it's time not to */
        while(!wd->quit_bit) {                                                           while(!wd->quit_bit) {
                vrFrame();                                                                       vrFrame();
                update_world(wd);                                                                update_world(wd);
        }                                                                                }
 
        /*********************/                                                          /*********************/
        /*** close up shop ***/                                                          /*** close up shop ***/
        /*********************/                                                          /*********************/
        exit_application(0);                                                             exit_application(0);
}                                                                                }
 
 
/********************************************************************/           /********************************************************************/
/* exit_application(): clean up anything started by the application */           /* exit_application(): clean up anything started by the application */
/*   (forked processes, open files, open sockets, etc.)             */           /*   (forked processes, open files, open sockets, etc.)             */
/********************************************************************/           /********************************************************************/
void exit_application(int signal)                                                void exit_application(int signal)
{                                                                                {
        end_world();                                                                     end_world();
 
        vrExit();                                                                        vrExit();
 
        exit(0);                                                                         exit(0);
}                                                                                }
 
 
 
/* ----------------8<-----------------8<-----------------8<----------------*/    /* ----------------8<-----------------8<-----------------8<----------------*/
/* In a non-example applicatation, the following would be a separate file. */    /* In a non-example applicatation, the following would be a separate file. */
 
                /**********************************/                                             /**********************************/
                /**********************************/                                             /**********************************/
                /** The World Simulation section **/                                             /** The World Simulation section **/
                /**********************************/                                             /**********************************/
                /**********************************/                                             /**********************************/
 
#ifdef USE_SOCKETS /* { */                                                       #ifdef USE_SOCKETS /* { */
static int      listen_sock = -1;       /* socket to receive commands */         static int      listen_sock = -1;       /* socket to receive commands */
                                        /*   listen_sock is not in wd                                                    /*   listen_sock is not in wd        
                                        /*   because it needs to be                                                      /*   because it needs to be          
                                        /*   available to exit_application()                                             /*   available to exit_application() 
                                        /*   which can have no arguments.                                                /*   which can have no arguments.    
#endif /* } USE_SOCKETS */                                                       #endif /* } USE_SOCKETS */
 
 
/****************************************************************/               /****************************************************************/
/* init_world(): create the initial conditions of the dynamic   */               /* init_world(): create the initial conditions of the dynamic   */
/*   simulation.  If the "VR_PORT" environment variable is set, */               /*   simulation.  If the "VR_PORT" environment variable is set, */
/*   then its value is used as the initial server socket port.  */               /*   then its value is used as the initial server socket port.  */
/*   Otherwise, the arbitrarily chosen port number 4000 is used.*/               /*   Otherwise, the arbitrarily chosen port number 4000 is used.*/
/*   Since IRIX, and perhaps other Unicies have a "feature" in  */               /*   Since IRIX, and perhaps other Unicies have a "feature" in  */
/*   which a socket port isn't usable again until after 60      */               /*   which a socket port isn't usable again until after 60      */
/*   seconds have passed since the connection was closed, if the*/               /*   seconds have passed since the connection was closed, if the*/
/*   initial socket isn't available, we try the next two ports  */               /*   initial socket isn't available, we try the next two ports  */
/*   in succession.  The selected port is reported to the tty.  */               /*   in succession.  The selected port is reported to the tty.  */
/****************************************************************/               /****************************************************************/
void init_world(WorldDataType *wd)                                               void init_world(WorldDataType *wd)
{                                                                                {
#ifdef USE_SOCKETS /* { */                                                       #ifdef USE_SOCKETS /* { */
        int     inet_port;                                                               int     inet_port;
        int     inet_port_max;                                                           int     inet_port_max;
        char    host_machine[128];                                                       char    host_machine[128];
#endif /* } USE_SOCKETS */                                                       #endif /* } USE_SOCKETS */
 
        /*************************/                                                      /*************************/
        /* set world state flags */                                                      /* set world state flags */
        vrLockWriteSet(wd->lock);                                                        vrLockWriteSet(wd->lock);
        wd->quit_bit = 0;                                                                wd->quit_bit = 0;
        vrLockWriteRelease(wd->lock);                                                    vrLockWriteRelease(wd->lock);
 
        /***************************/                                                    /***************************/
        /* setup the world content */                                                    /* setup the world content */
        init_objects(wd);                                                                init_objects(wd);
 
#ifdef USE_SOCKETS /* { */                                                       #ifdef USE_SOCKETS /* { */
        /******************************/                                                 /******************************/
        /* initialize the socket port */                                                 /* initialize the socket port */
        gethostname(host_machine, 128);                                                  gethostname(host_machine, 128);
 
        /* loop through N possible internet ports to hopefully find one that             /* loop through N possible internet ports to hopefully find one that 
        if (getenv("VR_PORT") != NULL)                                                   if (getenv("VR_PORT") != NULL)
                inet_port = atoi(getenv("VR_PORT"));                                             inet_port = atoi(getenv("VR_PORT"));
        else    inet_port = 4000;                                                        else    inet_port = 4000;
        for (inet_port_max = inet_port + 2; listen_sock < 0 && inet_port <= i            for (inet_port_max = inet_port + 2; listen_sock < 0 && inet_port <= i
                printf("Port %d -- ", inet_port);                                                printf("Port %d -- ", inet_port);
                fflush(stdout);                                                                  fflush(stdout);
                listen_sock = vrSocketCreateListen(&inet_port, 0);                               listen_sock = vrSocketCreateListen(&inet_port, 0);
        }                                                                                }
        inet_port--;                                                                     inet_port--;
        if (listen_sock < 0)                                                             if (listen_sock < 0)
                printf("WARNING: Unable to find an open socket port.\n");                        printf("WARNING: Unable to find an open socket port.\n");
        else    printf("\rConnect to '%s:%d' to send commands to the simulati            else    printf("\rConnect to '%s:%d' to send commands to the simulati
#endif /* } USE_SOCKETS */                                                       #endif /* } USE_SOCKETS */
}                                                                                }
 
 
/***************************************************************/                /***************************************************************/
/* init_objects(): place objects into the world data structure */                /* init_objects(): place objects into the world data structure */
/*   at some initial positions.                                */                /*   at some initial positions.                                */
/***************************************************************/                /***************************************************************/
void init_objects(WorldDataType *wd)                                             void init_objects(WorldDataType *wd)
{                                                                                {
        int     objnum = 0;                                                              int     objnum = 0;
 
        vrLockWriteSet(wd->lock);                                                        vrLockWriteSet(wd->lock);
 
        /* object 1 - a blue cube */                                                     /* object 1 - a blue cube */
        wd->object[objnum].type = vw_normal;                                             wd->object[objnum].type = vw_normal;
        wd->object[objnum].shape = cube;                                                 wd->object[objnum].shape = cube;
        wd->object[objnum].size = 1.0;                                                   wd->object[objnum].size = 1.0;
        wd->object[objnum].color[0] = 100;                                               wd->object[objnum].color[0] = 100;
        wd->object[objnum].color[1] = 100;                                               wd->object[objnum].color[1] = 100;
        wd->object[objnum].color[2] = 255;                                               wd->object[objnum].color[2] = 255;
        wd->object[objnum].x =  0.0;                                                     wd->object[objnum].x =  0.0;
        wd->object[objnum].y =  5.0;                                                     wd->object[objnum].y =  5.0;
        wd->object[objnum].z = -4.0;                                                     wd->object[objnum].z = -4.0;
        objnum++;                                                                        objnum++;
 
        /* object 2 - a red pyramid */                                                   /* object 2 - a red pyramid */
        wd->object[objnum].type = vw_normal;                                             wd->object[objnum].type = vw_normal;
        wd->object[objnum].shape = pyramid;                                              wd->object[objnum].shape = pyramid;
        wd->object[objnum].size = 1.0;                                                   wd->object[objnum].size = 1.0;
        wd->object[objnum].color[0] = 255;                                               wd->object[objnum].color[0] = 255;
        wd->object[objnum].color[1] = 100;                                               wd->object[objnum].color[1] = 100;
        wd->object[objnum].color[2] = 100;                                               wd->object[objnum].color[2] = 100;
        wd->object[objnum].x = -4.0;                                                     wd->object[objnum].x = -4.0;
        wd->object[objnum].y =  5.0;                                                     wd->object[objnum].y =  5.0;
        wd->object[objnum].z = -4.0;                                                     wd->object[objnum].z = -4.0;
        objnum++;                                                                        objnum++;
 
        /* object 3 - an upside-down green pyramid */                                    /* object 3 - an upside-down green pyramid */
        wd->object[objnum].type = vw_normal;                                             wd->object[objnum].type = vw_normal;
        wd->object[objnum].shape = ud_pyramid;                                           wd->object[objnum].shape = ud_pyramid;
        wd->object[objnum].size = 1.0;                                                   wd->object[objnum].size = 1.0;
        wd->object[objnum].color[0] = 100;                                               wd->object[objnum].color[0] = 100;
        wd->object[objnum].color[1] = 255;                                               wd->object[objnum].color[1] = 255;
        wd->object[objnum].color[2] = 100;                                               wd->object[objnum].color[2] = 100;
        wd->object[objnum].x =  4.0;                                                     wd->object[objnum].x =  4.0;
        wd->object[objnum].y =  5.0;                                                     wd->object[objnum].y =  5.0;
        wd->object[objnum].z = -4.0;                                                     wd->object[objnum].z = -4.0;
        objnum++;                                                                        objnum++;
 
        /* object 4 - a user interface button */                                         /* object 4 - a user interface button */
        wd->object[objnum].type = ui_button;                                             wd->object[objnum].type = ui_button;
        wd->object[objnum].shape = cube;                                                 wd->object[objnum].shape = cube;
        wd->object[objnum].size = 0.4;                                                   wd->object[objnum].size = 0.4;
        wd->object[objnum].ui_button_value = 1;                                          wd->object[objnum].ui_button_value = 1;
        wd->object[objnum].color[0] = 200;                                               wd->object[objnum].color[0] = 200;
        wd->object[objnum].color[1] = 100;                                               wd->object[objnum].color[1] = 100;
        wd->object[objnum].color[2] = 255;                                               wd->object[objnum].color[2] = 255;
        wd->object[objnum].x = -4.0;                                                     wd->object[objnum].x = -4.0;
        wd->object[objnum].y =  4.0;                                                     wd->object[objnum].y =  4.0;
        wd->object[objnum].z = -2.0;                                                     wd->object[objnum].z = -2.0;
        objnum++;                                                                        objnum++;
 
                                                                                         /* object 5 - a user interface slider */
                                                                                         wd->object[objnum].type = ui_slider;
                                                                                         wd->object[objnum].shape = cube;
                                                                                         wd->object[objnum].size = 0.4;
                                                                                         wd->object[objnum].ui_slider_value = 1.0;
                                                                                         wd->object[objnum].color[0] = 208;
                                                                                         wd->object[objnum].color[1] = 113;
                                                                                         wd->object[objnum].color[2] =  33;
                                                                                         wd->object[objnum].x = -4.0;
                                                                                         wd->object[objnum].y =  4.0;
                                                                                         wd->object[objnum].z = -1.0;
                                                                                         objnum++;
                                                                                
        wd->number_of_objects = objnum;                                                  wd->number_of_objects = objnum;
        wd->contacted_object = -1;                                                       wd->contacted_object = -1;
        wd->last_contacted_object = wd->contacted_object;                                wd->last_contacted_object = wd->contacted_object;
 
        /* sanity test */                                                                /* sanity test */
        if (objnum > MAX_OBJECTS) {                                                      if (objnum > MAX_OBJECTS) {
                printf("DANGER: Number of objects (%d), exceeds maximum allow                    printf("DANGER: Number of objects (%d), exceeds maximum allow
        }                                                                                }
 
        vrLockWriteRelease(wd->lock);                                                    vrLockWriteRelease(wd->lock);
}                                                                                }
 
 
/*******************************************************/                        /*******************************************************/
/* end_world(): clean up anything opened by simulation */                        /* end_world(): clean up anything opened by simulation */
/*******************************************************/                        /*******************************************************/
void end_world()                                                                 void end_world()
{                                                                                {
#ifdef USE_SOCKETS /* { */                                                       #ifdef USE_SOCKETS /* { */
        vrSocketClose(listen_sock);                                                      vrSocketClose(listen_sock);
#endif /* } USE_SOCKETS */                                                       #endif /* } USE_SOCKETS */
}                                                                                }
 
 
/*********************************************************************/          /*********************************************************************/
/* update_world(): In this version, we handle the user interactions. */          /* update_world(): In this version, we handle the user interactions. */
/*   Both selecting, and moving the contacted object.                */          /*   Both selecting, and moving the contacted object.                */
/*********************************************************************/          /*********************************************************************/
void update_world(WorldDataType *wd)                                             void update_world(WorldDataType *wd)
{                                                                                {
#define JS_EPSILON      0.125                           /* the dead-zone befo    #define JS_EPSILON      0.125                           /* the dead-zone befo
#define MOVE_FACTOR     2.5                             /* a scale factor to     #define MOVE_FACTOR     2.5                             /* a scale factor to 
#define TURN_FACTOR     25.0                            /* a scale factor to     #define TURN_FACTOR     25.0                            /* a scale factor to 
#define SUB_JS_EPSILON(a)       ((a)-copysign(JS_EPSILON,(a)))  /* a macro to    #define SUB_JS_EPSILON(a)       ((a)-copysign(JS_EPSILON,(a)))  /* a macro to
#ifdef USE_SOCKETS /* { */                                                       #ifdef USE_SOCKETS /* { */
static  char    *help_msg = "Socket commands:\n"                                 static  char    *help_msg = "Socket commands:\n"
                                "\thelp -- this message\n"                                                       "\thelp -- this message\n"
                                "\tquit -- quit the application\n"                                               "\tquit -- quit the application\n"
                                "\tclose -- close the connection\n"                                              "\tclose -- close the connection\n"
                                "\treset -- reset the application\n"                                             "\treset -- reset the application\n"
                                "\tbutton? -- report the value of the UI butt                                    "\tbutton? -- report the value of the UI butt
                                "\tbutton on -- set the value of the UI butto                                    "\tbutton on -- set the value of the UI butto
                                "\tbutton off -- set the value of the UI butt                                    "\tbutton off -- set the value of the UI butt
                                                                                                                 "\tslider? -- report the value of the UI slid
                                                                                                                 "\tslider <n> -- set the value of the UI slid
                                "\tmove cube up -- translate the cube up 2 fe                                    "\tmove cube up -- translate the cube up 2 fe
                                "\tmove cube down -- translate the cube down                                     "\tmove cube down -- translate the cube down 
                                "\twhere -- report the user's position in the                                    "\twhere -- report the user's position in the
                                "\twhere am i -- report the user's position i                                    "\twhere am i -- report the user's position i
                                "\tshow ActiveWalls -- report some CAVE confi                                    "\tshow ActiveWalls -- report some CAVE confi
                "";                                                                              "";
static  int     cmd_socket = -1;        /* socket to get commands from */        static  int     cmd_socket = -1;        /* socket to get commands from */
static  char    buf[128];               /* socket read buffer          */        static  char    buf[128];               /* socket read buffer          */
static  char    msg[128];               /* socket send buffer          */        static  char    msg[128];               /* socket send buffer          */
        int     result;                 /* result of reading a socket  */                int     result;                 /* result of reading a socket  */
#endif /* } USE_SOCKETS */                                                       #endif /* } USE_SOCKETS */
 
static  vrTime          last_time = -1.0;               /* initially set to a    static  vrTime          last_time = -1.0;               /* initially set to a
        vrTime          sim_time = vrCurrentSimTime();  /* the current time o            vrTime          sim_time = vrCurrentSimTime();  /* the current time o
static  vrPoint         last_wand_vw_locpnt;            /* VW location of the    static  vrPoint         last_wand_vw_locpnt;            /* VW location of the
        vrPoint         wand_vw_locpnt;                 /* current location o            vrPoint         wand_vw_locpnt;                 /* current location o
        vrPoint         wand_rw_locpnt;                 /* current location o            vrPoint         wand_rw_locpnt;                 /* current location o
#define last_wand_vw_loc last_wand_vw_locpnt.v                                   #define last_wand_vw_loc last_wand_vw_locpnt.v
#define wand_vw_location wand_vw_locpnt.v                                        #define wand_vw_location wand_vw_locpnt.v
#define wand_rw_location wand_rw_locpnt.v                                        #define wand_rw_location wand_rw_locpnt.v
        vrVector        wand_rw_pointvec;               /* current vector poi            vrVector        wand_rw_pointvec;               /* current vector poi
        double          delta_time;                     /* time since last up            double          delta_time;                     /* time since last up
        double          delta_move;                     /* distance an object            double          delta_move;                     /* distance an object
        double          joy_x, joy_y;                   /* Joystick values */            double          joy_x, joy_y;                   /* Joystick values */
        int             touch_obj = -1;                 /* the currently touc            int             touch_obj = -1;                 /* the currently touc
        int             objnum;                         /* for looping throuh            int             objnum;                         /* for looping throuh
        ObjectType      *object;                        /* pointer to object             ObjectType      *object;                        /* pointer to object 
        float           size;                           /* size of object --             float           size;                           /* size of object -- 
        int             button_value;                                                    int             button_value;
                                                                                         float           slider_value;
 
        /*****************************************************/                          /*****************************************************/
        /** Determine delta time from last simulation frame **/                          /** Determine delta time from last simulation frame **/
        /*****************************************************/                          /*****************************************************/
        if (last_time == -1.0)                                                           if (last_time == -1.0)
                delta_time = 0.0;                                                                delta_time = 0.0;
        else    delta_time = sim_time - last_time;                                       else    delta_time = sim_time - last_time;
        last_time = sim_time;                           /* now that delta_tim            last_time = sim_time;                           /* now that delta_tim
 
        /* skip the update if the delta isn't big enough */                              /* skip the update if the delta isn't big enough */
        if (delta_time <= 0.0)  /* can also choose a non-zero epsilon */                 if (delta_time <= 0.0)  /* can also choose a non-zero epsilon */
                return;                                                                          return;
 
        /**********************************/                                             /**********************************/
        /** Handle Manipulation via wand **/                                             /** Handle Manipulation via wand **/
        /**********************************/                                             /**********************************/
 
        /**********************************************************/                     /**********************************************************/
        /* check for contact between the wand and all the objects */                     /* check for contact between the wand and all the objects */
        vrLockReadSet(wd->lock);                                                         vrLockReadSet(wd->lock);
 
        vrPointGetVWFromUser6sensor(&wand_vw_locpnt, 0, WAND_SENSOR);                    vrPointGetVWFromUser6sensor(&wand_vw_locpnt, 0, WAND_SENSOR);
        vrPointGetRWFrom6sensor(&wand_rw_locpnt, WAND_SENSOR);                           vrPointGetRWFrom6sensor(&wand_rw_locpnt, WAND_SENSOR);
 
        for (objnum = 0; objnum < wd->number_of_objects; objnum++) {                     for (objnum = 0; objnum < wd->number_of_objects; objnum++) {
                object = &(wd->object[objnum]);                                                  object = &(wd->object[objnum]);
                size = object->size;                                                             size = object->size;
 
                switch (object->type) {                                                          switch (object->type) {
                case vw_normal: /* determine contact with normal object */                       case vw_normal: /* determine contact with normal object */
                        if ( (wand_vw_location[VR_X] < object->x + size)                                 if ( (wand_vw_location[VR_X] < object->x + size)
                          && (wand_vw_location[VR_X] > object->x - size)                                   && (wand_vw_location[VR_X] > object->x - size)
                          && (wand_vw_location[VR_Y] < object->y + size)                                   && (wand_vw_location[VR_Y] < object->y + size)
                          && (wand_vw_location[VR_Y] > object->y - size)                                   && (wand_vw_location[VR_Y] > object->y - size)
                          && (wand_vw_location[VR_Z] < object->z + size)                                   && (wand_vw_location[VR_Z] < object->z + size)
                          && (wand_vw_location[VR_Z] > object->z - size) ) {                               && (wand_vw_location[VR_Z] > object->z - size) ) {
                                touch_obj = objnum;                                                              touch_obj = objnum;
                        }                                                                                }
                        break;                                                                           break;
                                                                                                 
                case ui_button: /* determine contact with button widget */                       case ui_button: /* determine contact with button widget */
                        if ( (wand_rw_location[VR_X] < object->x + size)                                 if ( (wand_rw_location[VR_X] < object->x + size)
                          && (wand_rw_location[VR_X] > object->x - size)                                   && (wand_rw_location[VR_X] > object->x - size)
                          && (wand_rw_location[VR_Y] < object->y + size)                                   && (wand_rw_location[VR_Y] < object->y + size)
                          && (wand_rw_location[VR_Y] > object->y - size)                                   && (wand_rw_location[VR_Y] > object->y - size)
                          && (wand_rw_location[VR_Z] < object->z + size)                                   && (wand_rw_location[VR_Z] < object->z + size)
                          && (wand_rw_location[VR_Z] > object->z - size) ) {                               && (wand_rw_location[VR_Z] > object->z - size) ) {
                                touch_obj = objnum;                                                              touch_obj = objnum;
                        }                                                                                }
                        break;                                                                           break;
                                                                                
                                                                                                 case ui_slider: /* determine contact with slider widget */
                                                                                                         /* check intersection with the (moving) grab bar */
                                                                                                         /* NOTE: this crudely assumes vertically aligned slid
                                                                                                         if (
                                                                                                                 /* contact with the grab-plate */
                                                                                                             ((wand_rw_location[VR_X] < object->x + size)
                                                                                                           && (wand_rw_location[VR_X] > object->x - size)
                                                                                                           && (wand_rw_location[VR_Y] < (object->y + object->u
                                                                                                           && (wand_rw_location[VR_Y] > (object->y + object->u
                                                                                                           && (wand_rw_location[VR_Z] < object->z + size)
                                                                                                           && (wand_rw_location[VR_Z] > object->z - size))
                                                                                                          ||     /* or contact with the slider-bar */
                                                                                                             ((wand_rw_location[VR_X] < object->x + size * 0.2
                                                                                                           && (wand_rw_location[VR_X] > object->x - size * 0.2
                                                                                                           && (wand_rw_location[VR_Y] < object->y + size * SLI
                                                                                                           && (wand_rw_location[VR_Y] > object->y - size * SLI
                                                                                                           && (wand_rw_location[VR_Z] < object->z + size * 0.2
                                                                                                           && (wand_rw_location[VR_Z] > object->z - size * 0.2
                                                                                                                 ) {
                                                                                                                 touch_obj = objnum;
                                                                                                         }
                                                                                                         break;
                }                                                                                }
        }                                                                                }
        vrLockReadRelease(wd->lock);                                                     vrLockReadRelease(wd->lock);
 
 
        /*************************************************************/                  /*************************************************************/
        /* perform type-appropriate actions for the contacted object */                  /* perform type-appropriate actions for the contacted object */
 
        /* NOTE: ideally we would use write-locks specific to each */                    /* NOTE: ideally we would use write-locks specific to each */
        /*   object, and only where that object is being changed.  */                    /*   object, and only where that object is being changed.  */
        vrLockWriteSet(wd->lock);       /* lock while changing an object's lo            vrLockWriteSet(wd->lock);       /* lock while changing an object's lo
        wd->last_contacted_object = wd->contacted_object;                                wd->last_contacted_object = wd->contacted_object;
        wd->contacted_object = touch_obj;                                                wd->contacted_object = touch_obj;
        if (wd->contacted_object != -1) {                                                if (wd->contacted_object != -1) {
                object = &(wd->object[wd->contacted_object]);                                    object = &(wd->object[wd->contacted_object]);
                size = object->size;                                                             size = object->size;
 
                switch (object->type) {                                                          switch (object->type) {
                case vw_normal: /* perform manipulation on normal object */                      case vw_normal: /* perform manipulation on normal object */
                        /* when left wand button is pressed, a contacted VW o                            /* when left wand button is pressed, a contacted VW o
                        if (vrGet2switchValue(1)) {                                                      if (vrGet2switchValue(1)) {
 
                                object->x += (wand_vw_location[VR_X] - last_w                                    object->x += (wand_vw_location[VR_X] - last_w
                                object->y += (wand_vw_location[VR_Y] - last_w                                    object->y += (wand_vw_location[VR_Y] - last_w
                                object->z += (wand_vw_location[VR_Z] - last_w                                    object->z += (wand_vw_location[VR_Z] - last_w
                        }                                                                                }
                        break;                                                                           break;
 
                case ui_button: /* perform manipulation on button widget */                      case ui_button: /* perform manipulation on button widget */
                        /* this code only needed for direct-control of button                            /* this code only needed for direct-control of button
 
                        /* CONTACT-trigger: when we begin to touch a button,                             /* CONTACT-trigger: when we begin to touch a button, 
                        if (wd->contacted_object != wd->last_contacted_object                            if (wd->contacted_object != wd->last_contacted_object
                                object->ui_button_value ^= 1;                                                    object->ui_button_value ^= 1;
                        }                                                                                }
                        break;                                                                           break;
                                                                                
                                                                                                 case ui_slider: /* perform manipulation on slider widget */
                                                                                                         /* this code only needed for direct-control of slider
                                                                                                         /* NOTE: this crudely assumes vertically aligned slid
                                                                                
                                                                                                         /* BUTTON-trigger: when left button is pressed, grab 
                                                                                                         /* NOTE: should also have a contact-trigger version *
                                                                                                         if (vrGet2switchValue(1)) {
                                                                                                                 object->ui_slider_value = (wand_rw_location[V
                                                                                                                 /* put limits on how far the grab-bar moves *
                                                                                                                 if (object->ui_slider_value > 1.0)
                                                                                                                         object->ui_slider_value = 1.0;
                                                                                                                 if (object->ui_slider_value < -1.0)
                                                                                                                         object->ui_slider_value = -1.0;
                                                                                
                                                                                                         }
                                                                                                         break;
                }                                                                                }
        }                                                                                }
        vrLockWriteRelease(wd->lock);                                                    vrLockWriteRelease(wd->lock);
 
        /******************************************************************/             /******************************************************************/
        /* store the current wand location for next time through the loop */             /* store the current wand location for next time through the loop */
        last_wand_vw_loc[VR_X] = wand_vw_location[VR_X];                                 last_wand_vw_loc[VR_X] = wand_vw_location[VR_X];
        last_wand_vw_loc[VR_Y] = wand_vw_location[VR_Y];                                 last_wand_vw_loc[VR_Y] = wand_vw_location[VR_Y];
        last_wand_vw_loc[VR_Z] = wand_vw_location[VR_Z];                                 last_wand_vw_loc[VR_Z] = wand_vw_location[VR_Z];
 
 
        /************************************************/                               /************************************************/
        /** Handle Travel via wand and virtual devices **/                               /** Handle Travel via wand and virtual devices **/
        /************************************************/                               /************************************************/
 
        vrLockReadSet(wd->lock);        /* lock while getting the UI values *            vrLockReadSet(wd->lock);        /* lock while getting the UI values *
        button_value = wd->object[3].ui_button_value;                                    button_value = wd->object[3].ui_button_value;
                                                                                         slider_value = wd->object[4].ui_slider_value;
        vrLockReadRelease(wd->lock);                                                     vrLockReadRelease(wd->lock);
 
        /* only travel if UI-button is on */                                             /* only travel if UI-button is on */
        if (button_value) {                                                              if (button_value) {
                /* pressing the right wand button resets us to the initial po                    /* pressing the right wand button resets us to the initial po
                if (vrGet2switchValue(3)) {                                                      if (vrGet2switchValue(3)) {
                        vrUserTravelReset(VR_ALLUSERS);                                                  vrUserTravelReset(VR_ALLUSERS);
                }                                                                                }
 
                /* use wand joystick to fly through world */                                     /* use wand joystick to fly through world */
                joy_x = vrGetValuatorValue(0);                                                   joy_x = vrGetValuatorValue(0);
                joy_y = vrGetValuatorValue(1);                                                   joy_y = vrGetValuatorValue(1);
 
                if (fabs(joy_x) > JS_EPSILON)                                                    if (fabs(joy_x) > JS_EPSILON)
                        vrUserTravelRotateId(VR_ALLUSERS, VR_Y, (delta_time *                            vrUserTravelRotateId(VR_ALLUSERS, VR_Y, (delta_time *
 
                if (fabs(joy_y) > JS_EPSILON) {                                                  if (fabs(joy_y) > JS_EPSILON) {
                        delta_move = delta_time * SUB_JS_EPSILON(joy_y) * MOV                            delta_move = delta_time * SUB_JS_EPSILON(joy_y) * MOV
                        vrVectorGetRWFrom6sensorDir(&wand_rw_pointvec, WAND_S                            vrVectorGetRWFrom6sensorDir(&wand_rw_pointvec, WAND_S
                        vrUserTravelTranslate3d(VR_ALLUSERS,                                             vrUserTravelTranslate3d(VR_ALLUSERS,
                                wand_rw_pointvec.v[VR_X] * delta_move,                                           wand_rw_pointvec.v[VR_X] * delta_move,
                                wand_rw_pointvec.v[VR_Y] * delta_move,                                           wand_rw_pointvec.v[VR_Y] * delta_move,
                                wand_rw_pointvec.v[VR_Z] * delta_move);                                          wand_rw_pointvec.v[VR_Z] * delta_move);
                }                                                                                }
        }                                                                                }
 
 
#ifdef USE_SOCKETS /* { */                                                       #ifdef USE_SOCKETS /* { */
        /*******************************/                                                /*******************************/
        /* Handle Commands from socket */                                                /* Handle Commands from socket */
 
        /* if no connection (and a listen socket is open), see if someone is             /* if no connection (and a listen socket is open), see if someone is 
        if (cmd_socket < 0 && listen_sock >= 0) {                                        if (cmd_socket < 0 && listen_sock >= 0) {
                /* cmd_socket will be -1 when no one is connected */                             /* cmd_socket will be -1 when no one is connected */
                cmd_socket = vrSocketAnswer(listen_sock);                                        cmd_socket = vrSocketAnswer(listen_sock);
                if (cmd_socket > 0) {                                                            if (cmd_socket > 0) {
                        printf("New client connected.\n");                                               printf("New client connected.\n");
                        vrSocketSendMsg(cmd_socket, "Your wish is my command                             vrSocketSendMsg(cmd_socket, "Your wish is my command 
                }                                                                                }
        }                                                                                }
 
        /* if a connection, see if client sent a command.  If so, act on it *            /* if a connection, see if client sent a command.  If so, act on it *
        if (cmd_socket > 0) {                                                            if (cmd_socket > 0) {
                result = vrSocketReadMsgClean(cmd_socket, buf, 128);                             result = vrSocketReadMsgClean(cmd_socket, buf, 128);
                switch (result) {                                                                switch (result) {
                case -1:                                                                         case -1:
                        break;                                                                           break;
                case  0:                                                                         case  0:
                        printf("Client stopped communicating.\n");                                       printf("Client stopped communicating.\n");
                        close(cmd_socket);                                                               close(cmd_socket);
                        cmd_socket = -1;                                                                 cmd_socket = -1;
                        break;                                                                           break;
                default:                                                                         default:
                        printf("socket cmd = '%s'\n", buf);                                              printf("socket cmd = '%s'\n", buf);
                        /* parse command here -- very simple-minded parsing *                            /* parse command here -- very simple-minded parsing *
                        if (strcmp(buf, "quit") == 0) {                                                  if (strcmp(buf, "quit") == 0) {
                                /* set the world for termination */                                              /* set the world for termination */
                                wd->quit_bit = 1;                                                                wd->quit_bit = 1;
                        } else                                                                           } else
                        if (strcmp(buf, "help") == 0 || strcmp(buf, "?") == 0                            if (strcmp(buf, "help") == 0 || strcmp(buf, "?") == 0
                                /* give usage information */                                                     /* give usage information */
                                vrSocketSendMsg(cmd_socket, help_msg);                                           vrSocketSendMsg(cmd_socket, help_msg);
                        } else                                                                           } else
                        if (strcmp(buf, "close") == 0) {                                                 if (strcmp(buf, "close") == 0) {
                                /* close socket connection */                                                    /* close socket connection */
                                printf("Client ending communication.\n");                                        printf("Client ending communication.\n");
                                close(cmd_socket);                                                               close(cmd_socket);
                                cmd_socket = -1;                                                                 cmd_socket = -1;
                        } else                                                                           } else
                        if (strcmp(buf, "reset") == 0) {                                                 if (strcmp(buf, "reset") == 0) {
                                /* make the world as it was in the beginning                                     /* make the world as it was in the beginning 
                                init_objects(wd);                                                                init_objects(wd);
                                vrUserTravelReset(VR_ALLUSERS);                                                  vrUserTravelReset(VR_ALLUSERS);
                        } else                                                                           } else
                        if (strcmp(buf, "button?") == 0) {                                               if (strcmp(buf, "button?") == 0) {
                                /* report the user-interface button value */                                     /* report the user-interface button value */
                                sprintf(msg, "The button is %s.\n", (wd->obje                                    sprintf(msg, "The button is %s.\n", (wd->obje
                                vrSocketSendMsg(cmd_socket, msg);                                                vrSocketSendMsg(cmd_socket, msg);
                        } else                                                                           } else
                        if (strcmp(buf, "button on") == 0) {                                             if (strcmp(buf, "button on") == 0) {
                                /* turn the user-interface button on */                                          /* turn the user-interface button on */
                                wd->object[3].ui_button_value = 1;                                               wd->object[3].ui_button_value = 1;
                        } else                                                                           } else
                        if (strcmp(buf, "button off") == 0) {                                            if (strcmp(buf, "button off") == 0) {
                                /* turn the user-interface button on */                                          /* turn the user-interface button on */
                                wd->object[3].ui_button_value = 0;                                               wd->object[3].ui_button_value = 0;
                        } else                                                                           } else
                                                                                                         if (strcmp(buf, "slider?") == 0) {
                                                                                                                 /* report the user-interface slider value */
                                                                                                                 sprintf(msg, "The slider is at %.2f.\n", wd->
                                                                                                                 vrSocketSendMsg(cmd_socket, msg);
                                                                                                         } else
                                                                                                         if (strncmp(buf, "slider ", 7) == 0) {
                                                                                                                 /* set the user-interface slider value */
                                                                                                                 wd->object[4].ui_slider_value = atof(&(buf[7]
                                                                                                         } else
                        if (strcmp(buf, "move cube up") == 0) {                                          if (strcmp(buf, "move cube up") == 0) {
                                /* move the blue cube up 2.0 units */                                            /* move the blue cube up 2.0 units */
                                wd->object[0].y += 2.0;                                                          wd->object[0].y += 2.0;
                        } else                                                                           } else
                        if (strcmp(buf, "move cube down") == 0) {                                        if (strcmp(buf, "move cube down") == 0) {
                                /* move the blue cube down 2.0 units */                                          /* move the blue cube down 2.0 units */
                                wd->object[0].y -= 2.0;                                                          wd->object[0].y -= 2.0;
                        } else                                                                           } else
                        if (strcmp(buf, "where") == 0 || strcmp(buf, "where a                            if (strcmp(buf, "where") == 0 || strcmp(buf, "where a
                                /* report the user's location */                                                 /* report the user's location */
                                vrMatrix        *headmat;                                                        vrMatrix        *headmat;
                                vrPoint         headloc;                                                         vrPoint         headloc;
 
                                headmat = vrMatrixCreate();                                                      headmat = vrMatrixCreate();
                                vrMatrixGetRWFromUserHead(headmat, 0);                                           vrMatrixGetRWFromUserHead(headmat, 0);
                                vrPointGetVWFromUserMatrix(&headloc, 0, headm                                    vrPointGetVWFromUserMatrix(&headloc, 0, headm
                                sprintf(msg, "You are at (%f %f %f).\n", head                                    sprintf(msg, "You are at (%f %f %f).\n", head
                                vrSocketSendMsg(cmd_socket, msg);                                                vrSocketSendMsg(cmd_socket, msg);
                        } else                                                                           } else
                        if (strcmp(buf, "show ActiveWalls") == 0) {                                      if (strcmp(buf, "show ActiveWalls") == 0) {
                                /* report the type of graphics (VR) display *                                    /* report the type of graphics (VR) display *
                                sprintf(msg, "Application has %d active walls                                    sprintf(msg, "Application has %d active walls
                                vrSocketSendMsg(cmd_socket, msg);                                                vrSocketSendMsg(cmd_socket, msg);
                        } else                                                                           } else
                        /* default: */ {                                                                 /* default: */ {
                                vrSocketSendMsg(cmd_socket, "Unknown command.                                    vrSocketSendMsg(cmd_socket, "Unknown command.
                        }                                                                                }
 
                        /* prompt for another command (if socket still open)                             /* prompt for another command (if socket still open) 
                        if (cmd_socket > 0) {                                                            if (cmd_socket > 0) {
                                vrSocketSendMsg(cmd_socket, "Your wish is my                                     vrSocketSendMsg(cmd_socket, "Your wish is my 
                        }                                                                                }
                }                                                                                }
        }                                                                                }
#endif /* } USE_SOCKETS */                                                       #endif /* } USE_SOCKETS */
 
        /*********************************/                                              /*********************************/
        /* Handle Commands from keyboard */                                              /* Handle Commands from keyboard */
        if (vrGet2switchValue(0)) {                                                      if (vrGet2switchValue(0)) {
                wd->quit_bit = 1;                                                                wd->quit_bit = 1;
        }                                                                                }
 
        /****************************************************/                           /****************************************************/
        /* yield to allow other processes access to the CPU */                           /* yield to allow other processes access to the CPU */
        vrSleep(0);                                                                      vrSleep(0);
}                                                                                }
 
 
 
/* ----------------8<-----------------8<-----------------8<----------------*/    /* ----------------8<-----------------8<-----------------8<----------------*/
/* In a non-example applicatation, the following would be a separate file. */    /* In a non-example applicatation, the following would be a separate file. */
 
                /**************************/                                                     /**************************/
                /**************************/                                                     /**************************/
                /** The Graphics section **/                                                     /** The Graphics section **/
                /**************************/                                                     /**************************/
                /**************************/                                                     /**************************/
 
/* functions from wrs_shapes.c */                                                /* functions from wrs_shapes.c */
void    draw_floor();                                                            void    draw_floor();
void    draw_cube();                                                             void    draw_cube();
void    draw_pyramid();                                                          void    draw_pyramid();
void    draw_cube_outline();                                                     void    draw_cube_outline();
void    draw_pyramid_outline();                                                  void    draw_pyramid_outline();
void    draw_box_outlineonly(float x2, float x1, float y2, float y1, float z2    void    draw_box_outlineonly(float x2, float x1, float y2, float y1, float z2
 
 
/*********************************************************************/          /*********************************************************************/
/* init_gfx(): initialize general graphics properties (eg. lighting) */          /* init_gfx(): initialize general graphics properties (eg. lighting) */
/*********************************************************************/          /*********************************************************************/
void init_gfx()                                                                  void init_gfx()
{                                                                                {
        GLfloat location_0[4] = { 0.0, 10.0, 10.0, 1.0 /* 0 = directional, 1             GLfloat location_0[4] = { 0.0, 10.0, 10.0, 1.0 /* 0 = directional, 1 
                ambient_0[4] = { 0.2, 0.2, 0.2, 1.0 },                                           ambient_0[4] = { 0.2, 0.2, 0.2, 1.0 },
                diffuse_0[4] = { 0.8, 0.8, 0.8, 1.0 },                                           diffuse_0[4] = { 0.8, 0.8, 0.8, 1.0 },
                specular_0[4] = { 0.2, 0.2, 0.2, 1.0 };                                          specular_0[4] = { 0.2, 0.2, 0.2, 1.0 };
 
        /****************************************/                                       /****************************************/
        /* set the render initialization values */                                       /* set the render initialization values */
        glClearColor(0.0, 0.0, 0.0, 0.0);                                                glClearColor(0.0, 0.0, 0.0, 0.0);
        glClearDepth(1.0);                                                               glClearDepth(1.0);
 
        /********************************************************/                       /********************************************************/
        /* set the polygon shading/lighting/material parameters */                       /* set the polygon shading/lighting/material parameters */
        glShadeModel(GL_SMOOTH);                                                         glShadeModel(GL_SMOOTH);
 
        glEnable(GL_LIGHTING);                                                           glEnable(GL_LIGHTING);
 
        glLightfv(GL_LIGHT0, GL_POSITION, location_0);                                   glLightfv(GL_LIGHT0, GL_POSITION, location_0);
        glLightfv(GL_LIGHT0, GL_AMBIENT, ambient_0);                                     glLightfv(GL_LIGHT0, GL_AMBIENT, ambient_0);
        glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse_0);                                     glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse_0);
        glLightfv(GL_LIGHT0, GL_SPECULAR, specular_0);                                   glLightfv(GL_LIGHT0, GL_SPECULAR, specular_0);
        glEnable(GL_LIGHT0);                                                             glEnable(GL_LIGHT0);
 
        /* These two lines cause the vertex colors to be used (otherwise all             /* These two lines cause the vertex colors to be used (otherwise all 
        glColorMaterial(GL_FRONT, GL_AMBIENT_AND_DIFFUSE);                               glColorMaterial(GL_FRONT, GL_AMBIENT_AND_DIFFUSE);
        glEnable(GL_COLOR_MATERIAL);                                                     glEnable(GL_COLOR_MATERIAL);
 
        glEnable(GL_NORMALIZE); /* this is required when calling glScalef() w            glEnable(GL_NORMALIZE); /* this is required when calling glScalef() w
 
        /***************************/                                                    /***************************/
        /* set the line parameters */                                                    /* set the line parameters */
        glEnable(GL_LINE_SMOOTH);                                                        glEnable(GL_LINE_SMOOTH);
        glLineWidth(2.0);                                                                glLineWidth(2.0);
}                                                                                }
 
 
/*******************************************************************/            /*******************************************************************/
/* draw_world(): Now will render how ever many objects are in the  */            /* draw_world(): Now will render how ever many objects are in the  */
/*   world data structure.  The color, type (and maybe rotation)   */            /*   world data structure.  The color, type (and maybe rotation)   */
/*   are all now stored for each object, in addition to location.  */            /*   are all now stored for each object, in addition to location.  */
/*******************************************************************/            /*******************************************************************/
void draw_world(WorldDataType *wd, vrRenderInfo *rendinfo)                       void draw_world(WorldDataType *wd, vrRenderInfo *rendinfo)
{                                                                                {
static  GLfloat         location_0[4] = { 0.0, 10.0, 0.0, 1.0 /* 0 = directio    static  GLfloat         location_0[4] = { 0.0, 10.0, 0.0, 1.0 /* 0 = directio
static  char            msg[128];                       /* memory for text st    static  char            msg[128];                       /* memory for text st
        int             objnum;                         /* object counter */             int             objnum;                         /* object counter */
        ObjectType      *object;                        /* pointer to current            ObjectType      *object;                        /* pointer to current
        float           size;                           /* size of current ob            float           size;                           /* size of current ob
 
        /**************************************/                                         /**************************************/
        /* clear the screen -- very important */                                         /* clear the screen -- very important */
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);                              glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
        /********************************************************************            /********************************************************************
        /* update the light's location -- must be done independently for each            /* update the light's location -- must be done independently for each
        glLightfv(GL_LIGHT0, GL_POSITION, location_0);                                   glLightfv(GL_LIGHT0, GL_POSITION, location_0);
 
        /************************************/                                           /************************************/
        /* draw a short pointer at the wand */                                           /* draw a short pointer at the wand */
        glPushMatrix();                                                                  glPushMatrix();
                glColor3ub(100, 255, 255);      /* cyan */                                       glColor3ub(100, 255, 255);      /* cyan */
                vrRenderTransform6sensor(rendinfo, WAND_SENSOR);                                 vrRenderTransform6sensor(rendinfo, WAND_SENSOR);
                glRotatef(-90.0, 1.0, 0.0, 0.0);                                                 glRotatef(-90.0, 1.0, 0.0, 0.0);
                glScalef(0.15, 0.15, 0.15);                                                      glScalef(0.15, 0.15, 0.15);
                glTranslatef(0.0, -1.0, 0.0);   /* move the tip to (0,0,0) */                    glTranslatef(0.0, -1.0, 0.0);   /* move the tip to (0,0,0) */
                draw_pyramid_outline();                                                          draw_pyramid_outline();
        glPopMatrix();                                                                   glPopMatrix();
 
        /********************************************************/                       /********************************************************/
        /* draw all the objects, taking care to put each one in */                       /* draw all the objects, taking care to put each one in */
        /*   the proper coordinate system (virtual world space  */                       /*   the proper coordinate system (virtual world space  */
        /*   vs. real world space for the user-interface).      */                       /*   vs. real world space for the user-interface).      */
 
        /* draw the floor */                                                             /* draw the floor */
        glPushMatrix();                                                                  glPushMatrix();
                vrRenderTransformUserTravel(rendinfo);  /* change to virtual-                    vrRenderTransformUserTravel(rendinfo);  /* change to virtual-
                draw_floor();                                                                    draw_floor();
        glPopMatrix();                                                                   glPopMatrix();
 
        vrLockReadSet(wd->lock);        /* lock while reading info about obje            vrLockReadSet(wd->lock);        /* lock while reading info about obje
        for (objnum = 0; objnum < wd->number_of_objects; objnum++) {                     for (objnum = 0; objnum < wd->number_of_objects; objnum++) {
                object = &(wd->object[objnum]);                                                  object = &(wd->object[objnum]);
 
                glColor3ubv(object->color);                                                      glColor3ubv(object->color);
                glPushMatrix();                                                                  glPushMatrix();
                        size = object->size;                                                             size = object->size;
 
                        switch (object->type) {                                                          switch (object->type) {
 
                        case vw_normal: /* render normal object (in virtual w                            case vw_normal: /* render normal object (in virtual w
                                vrRenderTransformUserTravel(rendinfo);  /* ch                                    vrRenderTransformUserTravel(rendinfo);  /* ch
                                glTranslatef(object->x, object->y, object->z)                                    glTranslatef(object->x, object->y, object->z)
                                glScalef(size, size, size);                                                      glScalef(size, size, size);
 
                                switch (object->shape) {                                                         switch (object->shape) {
                                case cube:                                                                       case cube:
                                        if (objnum == wd->contacted_object)                                              if (objnum == wd->contacted_object)
                                                draw_cube_outline();                                                             draw_cube_outline();
                                        else    draw_cube();                                                             else    draw_cube();
                                        break;                                                                           break;
                                case sphere:                                                                     case sphere:
                                        if (objnum == wd->contacted_object)                                              if (objnum == wd->contacted_object)
                                                draw_sphere_outline();                                                           draw_sphere_outline();
                                        else    draw_sphere();                                                           else    draw_sphere();
                                        break;                                                                           break;
                                case pyramid:                                                                    case pyramid:
                                        if (objnum == wd->contacted_object)                                              if (objnum == wd->contacted_object)
                                                draw_pyramid_outline();                                                          draw_pyramid_outline();
                                        else    draw_pyramid();                                                          else    draw_pyramid();
                                        break;                                                                           break;
                                case ud_pyramid:                                                                 case ud_pyramid:
                                        glScalef(1.0, -1.0, 1.0);                                                        glScalef(1.0, -1.0, 1.0);
                                        if (objnum == wd->contacted_object)                                              if (objnum == wd->contacted_object)
                                                draw_pyramid_outline();                                                          draw_pyramid_outline();
                                        else    draw_pyramid();                                                          else    draw_pyramid();
                                        break;                                                                           break;
                                }                                                                                }
                                break;                                                                           break;
 
                        case ui_button: /* render button widget (in real worl                            case ui_button: /* render button widget (in real worl
                                /* widgets remain in real-world coordinates *                                    /* widgets remain in real-world coordinates *
                                glTranslatef(object->x, object->y, object->z)                                    glTranslatef(object->x, object->y, object->z)
#ifdef DRAW_UITEXT /* { */                                                       #ifdef DRAW_UITEXT /* { */
                                glPushMatrix();                                                                  glPushMatrix();
                                        glTranslatef(0.0, -(size + 0.5), 0.0)                                            glTranslatef(0.0, -(size + 0.5), 0.0)
 
                                        glRasterPos3f(0.0, 0.0, 0.0);   /* go                                            glRasterPos3f(0.0, 0.0, 0.0);   /* go
                                        if (object->ui_button_value)                                                     if (object->ui_button_value)
                                                vrRenderText(rendinfo, "on");                                                    vrRenderText(rendinfo, "on");
                                        else    vrRenderText(rendinfo, "off")                                            else    vrRenderText(rendinfo, "off")
                                glPopMatrix();                                                                   glPopMatrix();
#endif /* } DRAW_UITEXT */                                                       #endif /* } DRAW_UITEXT */
                                glScalef(size, size, size);                                                      glScalef(size, size, size);
                                glPushMatrix();                                                                  glPushMatrix();
 
                                        /* for now we'll ignore shape and all                                            /* for now we'll ignore shape and all
 
                                        /* draw the base box */                                                          /* draw the base box */
                                        if (objnum == wd->contacted_object)                                              if (objnum == wd->contacted_object)
                                                draw_cube_outline();                                                             draw_cube_outline();
                                        else    draw_cube();                                                             else    draw_cube();
 
                                        /* draw the button part */                                                       /* draw the button part */
                                        if (object->ui_button_value) {                                                   if (object->ui_button_value) {
                                                /* button is pressed (so bare                                                    /* button is pressed (so bare
 
                                                glTranslatef(0.4, 0.0, 0.0);                                                     glTranslatef(0.4, 0.0, 0.0);
                                                /* move color halfway to whit                                                    /* move color halfway to whit
                                                glColor3ub(                                                                      glColor3ub(     
                                                        object->color[0] + ((                                                            object->color[0] + ((
                                                        object->color[1] + ((                                                            object->color[1] + ((
                                                        object->color[2] + ((                                                            object->color[2] + ((
                                        } else {                                                                         } else {
                                                /* button is not pressed (so                                                     /* button is not pressed (so 
 
                                                glTranslatef(0.8, 0.0, 0.0);                                                     glTranslatef(0.8, 0.0, 0.0);
                                                /* move color halfway to blac                                                    /* move color halfway to blac
                                                glColor3ub(object->color[0]/2                                                    glColor3ub(object->color[0]/2
                                        }                                                                                }
                                        glScalef(0.7, 0.7, 0.7);                                                         glScalef(0.7, 0.7, 0.7);
                                        draw_cube_outline();                                                             draw_cube_outline();
                                glPopMatrix();                                                                   glPopMatrix();
 
                                break;                                                                           break;
                                                                                
                                                                                                         case ui_slider: /* render slider widget (in real worl
                                                                                                                 glTranslatef(object->x, object->y, object->z)
                                                                                 #ifdef DRAW_UITEXT /* { */
                                                                                                                 glPushMatrix();
                                                                                                                         glTranslatef(0.0, -SLIDER_LENGTH * si
                                                                                
                                                                                                                         sprintf(msg, "%5.2f", object->ui_slid
                                                                                                                         glRasterPos3f(0.0, 0.0, 0.0);   /* go
                                                                                                                         vrRenderText(rendinfo, msg);
                                                                                                                 glPopMatrix();
                                                                                 #endif /* } DRAW_UITEXT */
                                                                                                                 glScalef(size, size, size);
                                                                                
                                                                                                                 /* for now we'll ignore shape and all sliders
                                                                                                                 glPushMatrix();
                                                                                                                         /* the sliding rod */
                                                                                                                         glScalef(0.2, SLIDER_LENGTH, 0.2);
                                                                                                                         if (objnum == wd->contacted_object)
                                                                                                                                 draw_cube_outline();
                                                                                                                         else    draw_cube();
                                                                                                                 glPopMatrix();
                                                                                
                                                                                                                 glPushMatrix();
                                                                                                                         /* the value marker */
                                                                                                                         glColor3ub(object->color[0]/2, object
                                                                                                                         glTranslatef(0.0, object->ui_slider_v
                                                                                                                         glScalef(1.0, 0.2, 1.0);
                                                                                                                         draw_cube_outline();
                                                                                                                 glPopMatrix();
                                                                                                                 glPushMatrix();
                                                                                                                         glTranslatef(0.0, object->ui_slider_v
                                                                                                                         glScalef(0.201, 0.201, 0.201);
                                                                                                                         draw_cube_outline();
                                                                                                                 glPopMatrix();
                                                                                
                                                                                                                 break;
                        }                                                                                }
                glPopMatrix();                                                                   glPopMatrix();
        }                                                                                }
        /* NOTE: 2-D text is best rendered in a fixed location in the world *            /* NOTE: 2-D text is best rendered in a fixed location in the world *
 
        /*************************************************/                              /*************************************************/
        /* draw text indicating which object is contacted */                             /* draw text indicating which object is contacted */
        if (wd->contacted_object < 0) {                                                  if (wd->contacted_object < 0) {
                sprintf(msg, "Object contacted: none");                                          sprintf(msg, "Object contacted: none");
        } else {                                                                         } else {
                sprintf(msg, "Object contacted: %d", wd->contacted_object);                      sprintf(msg, "Object contacted: %d", wd->contacted_object);
        }                                                                                }
 
        vrLockReadRelease(wd->lock);                                                     vrLockReadRelease(wd->lock);
 
        glDisable(GL_LIGHTING);         /* make the text bright regardless of            glDisable(GL_LIGHTING);         /* make the text bright regardless of
        glColor3ub(255, 255, 255);      /* white */                                      glColor3ub(255, 255, 255);      /* white */
        glPushMatrix();                                                                  glPushMatrix();
                glTranslatef(-4.0, 7.0, -5.0);  /* on the front screen */                        glTranslatef(-4.0, 7.0, -5.0);  /* on the front screen */
 
                glRasterPos3f(0.0, 0.0, 0.0);   /* go to the 3D location */                      glRasterPos3f(0.0, 0.0, 0.0);   /* go to the 3D location */
                vrRenderText(rendinfo, msg);                                                     vrRenderText(rendinfo, msg);
        glPopMatrix();                                                                   glPopMatrix();
        glEnable(GL_LIGHTING);                                                           glEnable(GL_LIGHTING);
}                                                                                }