progs/egl/eglgears.c - platform/external/mesa3d - Gitiles

 /*
  * Copyright (C) 1999-2001  Brian Paul   All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  * and/or sell copies of the Software, and to permit persons to whom the
  * Software is furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included
  * in all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */

 /*
  * This is a port of the infamous "glxgears" demo to straight EGL
  * Port by Dane Rushton 10 July 2005
  *
  * No command line options.
  * Program runs for 5 seconds then exits, outputing framerate to console
  */

 #define EGL_EGLEXT_PROTOTYPES

 #include <assert.h>
 #include <math.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 #include <GL/gl.h>
 #include <EGL/egl.h>
 #include <EGL/eglext.h>

 #define MAX_CONFIGS 10
 #define MAX_MODES 100

 #define BENCHMARK

 #ifdef BENCHMARK

 /* XXX this probably isn't very portable */

 #include <sys/time.h>
 #include <unistd.h>

 /* return current time (in seconds) */
 static double
 current_time(void)
 {
    struct timeval tv;
 #ifdef __VMS
    (void) gettimeofday(&tv, NULL );
 #else
    struct timezone tz;
    (void) gettimeofday(&tv, &tz);
 #endif
    return (double) tv.tv_sec + tv.tv_usec / 1000000.0;
 }

 #else /*BENCHMARK*/

 /* dummy */
 static double
 current_time(void)
 {
    /* update this function for other platforms! */
    static double t = 0.0;
    static int warn = 1;
    if (warn) {
       fprintf(stderr, "Warning: current_time() not implemented!!\n");
       warn = 0;
    }
    return t += 1.0;
 }

 #endif /*BENCHMARK*/


 #ifndef M_PI
 #define M_PI 3.14159265
 #endif


 static GLfloat view_rotx = 20.0, view_roty = 30.0, view_rotz = 0.0;
 static GLint gear1, gear2, gear3;
 static GLfloat angle = 0.0;

 #if 0
 static GLfloat eyesep = 5.0;		/* Eye separation. */
 static GLfloat fix_point = 40.0;	/* Fixation point distance.  */
 static GLfloat left, right, asp;	/* Stereo frustum params.  */
 #endif


 /*
  *
  *  Draw a gear wheel.  You'll probably want to call this function when
  *  building a display list since we do a lot of trig here.
  *
  *  Input:  inner_radius - radius of hole at center
  *          outer_radius - radius at center of teeth
  *          width - width of gear
  *          teeth - number of teeth
  *          tooth_depth - depth of tooth
  */
 static void
 gear(GLfloat inner_radius, GLfloat outer_radius, GLfloat width,
      GLint teeth, GLfloat tooth_depth)
 {
    GLint i;
    GLfloat r0, r1, r2;
    GLfloat angle, da;
    GLfloat u, v, len;

    r0 = inner_radius;
    r1 = outer_radius - tooth_depth / 2.0;
    r2 = outer_radius + tooth_depth / 2.0;

    da = 2.0 * M_PI / teeth / 4.0;

    glShadeModel(GL_FLAT);

    glNormal3f(0.0, 0.0, 1.0);

    /* draw front face */
    glBegin(GL_QUAD_STRIP);
    for (i = 0; i <= teeth; i++) {
       angle = i * 2.0 * M_PI / teeth;
       glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
       glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
       if (i < teeth) {
 	 glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
 	 glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 		    width * 0.5);
       }
    }
    glEnd();

    /* draw front sides of teeth */
    glBegin(GL_QUADS);
    da = 2.0 * M_PI / teeth / 4.0;
    for (i = 0; i < teeth; i++) {
       angle = i * 2.0 * M_PI / teeth;

       glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 		 width * 0.5);
       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 		 width * 0.5);
    }
    glEnd();

    glNormal3f(0.0, 0.0, -1.0);

    /* draw back face */
    glBegin(GL_QUAD_STRIP);
    for (i = 0; i <= teeth; i++) {
       angle = i * 2.0 * M_PI / teeth;
       glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
       glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
       if (i < teeth) {
 	 glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 		    -width * 0.5);
 	 glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
       }
    }
    glEnd();

    /* draw back sides of teeth */
    glBegin(GL_QUADS);
    da = 2.0 * M_PI / teeth / 4.0;
    for (i = 0; i < teeth; i++) {
       angle = i * 2.0 * M_PI / teeth;

       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 		 -width * 0.5);
       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 		 -width * 0.5);
       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
       glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
    }
    glEnd();

    /* draw outward faces of teeth */
    glBegin(GL_QUAD_STRIP);
    for (i = 0; i < teeth; i++) {
       angle = i * 2.0 * M_PI / teeth;

       glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
       glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
       u = r2 * cos(angle + da) - r1 * cos(angle);
       v = r2 * sin(angle + da) - r1 * sin(angle);
       len = sqrt(u * u + v * v);
       u /= len;
       v /= len;
       glNormal3f(v, -u, 0.0);
       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
       glNormal3f(cos(angle), sin(angle), 0.0);
       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 		 width * 0.5);
       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 		 -width * 0.5);
       u = r1 * cos(angle + 3 * da) - r2 * cos(angle + 2 * da);
       v = r1 * sin(angle + 3 * da) - r2 * sin(angle + 2 * da);
       glNormal3f(v, -u, 0.0);
       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 		 width * 0.5);
       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 		 -width * 0.5);
       glNormal3f(cos(angle), sin(angle), 0.0);
    }

    glVertex3f(r1 * cos(0), r1 * sin(0), width * 0.5);
    glVertex3f(r1 * cos(0), r1 * sin(0), -width * 0.5);

    glEnd();

    glShadeModel(GL_SMOOTH);

    /* draw inside radius cylinder */
    glBegin(GL_QUAD_STRIP);
    for (i = 0; i <= teeth; i++) {
       angle = i * 2.0 * M_PI / teeth;
       glNormal3f(-cos(angle), -sin(angle), 0.0);
       glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
       glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
    }
    glEnd();
 }


 static void
 draw(void)
 {
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glPushMatrix();
    glRotatef(view_rotx, 1.0, 0.0, 0.0);
    glRotatef(view_roty, 0.0, 1.0, 0.0);
    glRotatef(view_rotz, 0.0, 0.0, 1.0);

    glPushMatrix();
    glTranslatef(-3.0, -2.0, 0.0);
    glRotatef(angle, 0.0, 0.0, 1.0);
    glCallList(gear1);
    glPopMatrix();

    glPushMatrix();
    glTranslatef(3.1, -2.0, 0.0);
    glRotatef(-2.0 * angle - 9.0, 0.0, 0.0, 1.0);
    glCallList(gear2);
    glPopMatrix();

    glPushMatrix();
    glTranslatef(-3.1, 4.2, 0.0);
    glRotatef(-2.0 * angle - 25.0, 0.0, 0.0, 1.0);
    glCallList(gear3);
    glPopMatrix();

    glPopMatrix();
 }


 /* new window size or exposure */
 static void
 reshape(int width, int height)
 {
    GLfloat h = (GLfloat) height / (GLfloat) width;

    glViewport(0, 0, (GLint) width, (GLint) height);

    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glFrustum(-1.0, 1.0, -h, h, 5.0, 60.0);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    glTranslatef(0.0, 0.0, -40.0);
 }


 static void
 init(void)
 {
    static GLfloat pos[4] = { 5.0, 5.0, 10.0, 0.0 };
    static GLfloat red[4] = { 0.8, 0.1, 0.0, 1.0 };
    static GLfloat green[4] = { 0.0, 0.8, 0.2, 1.0 };
    static GLfloat blue[4] = { 0.2, 0.2, 1.0, 1.0 };

    glLightfv(GL_LIGHT0, GL_POSITION, pos);
    glEnable(GL_CULL_FACE);
    glEnable(GL_LIGHTING);
    glEnable(GL_LIGHT0);
    glEnable(GL_DEPTH_TEST);

    /* make the gears */
    gear1 = glGenLists(1);
    glNewList(gear1, GL_COMPILE);
    glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, red);
    gear(1.0, 4.0, 1.0, 20, 0.7);
    glEndList();

    gear2 = glGenLists(1);
    glNewList(gear2, GL_COMPILE);
    glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, green);
    gear(0.5, 2.0, 2.0, 10, 0.7);
    glEndList();

    gear3 = glGenLists(1);
    glNewList(gear3, GL_COMPILE);
    glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, blue);
    gear(1.3, 2.0, 0.5, 10, 0.7);
    glEndList();

    glEnable(GL_NORMALIZE);
 }


 static void run_gears(EGLDisplay dpy, EGLSurface surf, int ttr)
 {
 	double st = current_time();
 	double ct = st;
 	int frames = 0;
 	GLfloat seconds, fps;

 	while (ct - st < ttr)
 	{
 		double tt = current_time();
 		double dt = tt - ct;
 		ct = tt;

 		/* advance rotation for next frame */
 		angle += 70.0 * dt;  /* 70 degrees per second */
 		if (angle > 3600.0)
 			angle -= 3600.0;

 		draw();

 		eglSwapBuffers(dpy, surf);


 		frames++;
 	}

 	seconds = ct - st;
 	fps = frames / seconds;
 	printf("%d frames in %3.1f seconds = %6.3f FPS\n", frames, seconds, fps);

 }


 int
 main(int argc, char *argv[])
 {
 	int maj, min;
 	EGLContext ctx;
 	EGLSurface screen_surf;
 	EGLConfig configs[MAX_CONFIGS];
 	EGLint numConfigs, i;
 	EGLBoolean b;
 	EGLDisplay d;
 	EGLint screenAttribs[10];
 	EGLModeMESA mode[MAX_MODES];
 	EGLScreenMESA screen;
 	EGLint count, chosenMode;
 	GLboolean printInfo = GL_FALSE;
 	EGLint width = 0, height = 0;

         /* parse cmd line args */
 	for (i = 1; i < argc; i++)
 	{
 		if (strcmp(argv[i], "-info") == 0)
 		{
 			printInfo = GL_TRUE;
 		}
 		else
 			printf("Warning: unknown parameter: %s\n", argv[i]);
 	}

 	/* DBR : Create EGL context/surface etc */
 	d = eglGetDisplay(EGL_DEFAULT_DISPLAY);
 	assert(d);

 	if (!eglInitialize(d, &maj, &min)) {
 		printf("eglgears: eglInitialize failed\n");
 		exit(1);
 	}

 	printf("eglgears: EGL version = %d.%d\n", maj, min);
 	printf("eglgears: EGL_VENDOR = %s\n", eglQueryString(d, EGL_VENDOR));

         /* XXX use ChooseConfig */
 	eglGetConfigs(d, configs, MAX_CONFIGS, &numConfigs);
 	eglGetScreensMESA(d, &screen, 1, &count);

 	if (!eglGetModesMESA(d, screen, mode, MAX_MODES, &count) || count == 0) {
 		printf("eglgears: eglGetModesMESA failed!\n");
 		return 0;
 	}

         /* Print list of modes, and find the one to use */
 	printf("eglgears: Found %d modes:\n", count);
 	for (i = 0; i < count; i++) {
 		EGLint w, h;
 		eglGetModeAttribMESA(d, mode[i], EGL_WIDTH, &w);
 		eglGetModeAttribMESA(d, mode[i], EGL_HEIGHT, &h);
 		printf("%3d: %d x %d\n", i, w, h);
 		if (w > width && h > height) {
 			width = w;
 			height = h;
                         chosenMode = i;
 		}
 	}
 	printf("eglgears: Using screen mode/size %d: %d x %d\n", chosenMode, width, height);

 	ctx = eglCreateContext(d, configs[0], EGL_NO_CONTEXT, NULL);
 	if (ctx == EGL_NO_CONTEXT) {
 		printf("eglgears: failed to create context\n");
 		return 0;
 	}

 	/* build up screenAttribs array */
 	i = 0;
 	screenAttribs[i++] = EGL_WIDTH;
 	screenAttribs[i++] = width;
 	screenAttribs[i++] = EGL_HEIGHT;
 	screenAttribs[i++] = height;
 	screenAttribs[i++] = EGL_NONE;

 	screen_surf = eglCreateScreenSurfaceMESA(d, configs[0], screenAttribs);
 	if (screen_surf == EGL_NO_SURFACE) {
 		printf("eglgears: failed to create screen surface\n");
 		return 0;
 	}

 	b = eglShowScreenSurfaceMESA(d, screen, screen_surf, mode[chosenMode]);
 	if (!b) {
 		printf("eglgears: show surface failed\n");
 		return 0;
 	}

 	b = eglMakeCurrent(d, screen_surf, screen_surf, ctx);
 	if (!b) {
 		printf("eglgears: make current failed\n");
 		return 0;
 	}

 	if (printInfo)
 	{
 		printf("GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
 		printf("GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
 		printf("GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
 		printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
 	}

 	init();
 	reshape(width, height);

         glDrawBuffer( GL_BACK );

 	run_gears(d, screen_surf, 5.0);

 	eglDestroySurface(d, screen_surf);
 	eglDestroyContext(d, ctx);
 	eglTerminate(d);

 	return 0;
 }
	/*
	* Copyright (C) 1999-2001 Brian Paul All Rights Reserved.
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the "Software"),
	* to deal in the Software without restriction, including without limitation
	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	* and/or sell copies of the Software, and to permit persons to whom the
	* Software is furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included
	* in all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
	* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
	* AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	*/

	/*
	* This is a port of the infamous "glxgears" demo to straight EGL
	* Port by Dane Rushton 10 July 2005
	*
	* No command line options.
	* Program runs for 5 seconds then exits, outputing framerate to console
	*/

	#define EGL_EGLEXT_PROTOTYPES

	#include <assert.h>
	#include <math.h>
	#include <stdlib.h>
	#include <stdio.h>
	#include <string.h>
	#include <GL/gl.h>
	#include <EGL/egl.h>
	#include <EGL/eglext.h>

	#define MAX_CONFIGS 10
	#define MAX_MODES 100

	#define BENCHMARK

	#ifdef BENCHMARK

	/* XXX this probably isn't very portable */

	#include <sys/time.h>
	#include <unistd.h>

	/* return current time (in seconds) */
	static double
	current_time(void)
	{
	struct timeval tv;
	#ifdef __VMS
	(void) gettimeofday(&tv, NULL );
	#else
	struct timezone tz;
	(void) gettimeofday(&tv, &tz);
	#endif
	return (double) tv.tv_sec + tv.tv_usec / 1000000.0;
	}

	#else /BENCHMARK/

	/* dummy */
	static double
	current_time(void)
	{
	/* update this function for other platforms! */
	static double t = 0.0;
	static int warn = 1;
	if (warn) {
	fprintf(stderr, "Warning: current_time() not implemented!!\n");
	warn = 0;
	}
	return t += 1.0;
	}

	#endif /BENCHMARK/


	#ifndef M_PI
	#define M_PI 3.14159265
	#endif


	static GLfloat view_rotx = 20.0, view_roty = 30.0, view_rotz = 0.0;
	static GLint gear1, gear2, gear3;
	static GLfloat angle = 0.0;

	#if 0
	static GLfloat eyesep = 5.0; /* Eye separation. */
	static GLfloat fix_point = 40.0; /* Fixation point distance. */
	static GLfloat left, right, asp; /* Stereo frustum params. */
	#endif


	/*
	*
	* Draw a gear wheel. You'll probably want to call this function when
	* building a display list since we do a lot of trig here.
	*
	* Input: inner_radius - radius of hole at center
	* outer_radius - radius at center of teeth
	* width - width of gear
	* teeth - number of teeth
	* tooth_depth - depth of tooth
	*/
	static void
	gear(GLfloat inner_radius, GLfloat outer_radius, GLfloat width,
	GLint teeth, GLfloat tooth_depth)
	{
	GLint i;
	GLfloat r0, r1, r2;
	GLfloat angle, da;
	GLfloat u, v, len;

	r0 = inner_radius;
	r1 = outer_radius - tooth_depth / 2.0;
	r2 = outer_radius + tooth_depth / 2.0;

	da = 2.0 * M_PI / teeth / 4.0;

	glShadeModel(GL_FLAT);

	glNormal3f(0.0, 0.0, 1.0);

	/* draw front face */
	glBegin(GL_QUAD_STRIP);
	for (i = 0; i <= teeth; i++) {
	angle = i * 2.0 * M_PI / teeth;
	glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
	glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
	if (i < teeth) {
	glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
	glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
	width * 0.5);
	}
	}
	glEnd();

	/* draw front sides of teeth */
	glBegin(GL_QUADS);
	da = 2.0 * M_PI / teeth / 4.0;
	for (i = 0; i < teeth; i++) {
	angle = i * 2.0 * M_PI / teeth;

	glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
	glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
	glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
	width * 0.5);
	glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
	width * 0.5);
	}
	glEnd();

	glNormal3f(0.0, 0.0, -1.0);

	/* draw back face */
	glBegin(GL_QUAD_STRIP);
	for (i = 0; i <= teeth; i++) {
	angle = i * 2.0 * M_PI / teeth;
	glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
	glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
	if (i < teeth) {
	glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
	-width * 0.5);
	glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
	}
	}
	glEnd();

	/* draw back sides of teeth */
	glBegin(GL_QUADS);
	da = 2.0 * M_PI / teeth / 4.0;
	for (i = 0; i < teeth; i++) {
	angle = i * 2.0 * M_PI / teeth;

	glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
	-width * 0.5);
	glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
	-width * 0.5);
	glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
	glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
	}
	glEnd();

	/* draw outward faces of teeth */
	glBegin(GL_QUAD_STRIP);
	for (i = 0; i < teeth; i++) {
	angle = i * 2.0 * M_PI / teeth;

	glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
	glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
	u = r2 * cos(angle + da) - r1 * cos(angle);
	v = r2 * sin(angle + da) - r1 * sin(angle);
	len = sqrt(u * u + v * v);
	u /= len;
	v /= len;
	glNormal3f(v, -u, 0.0);
	glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
	glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
	glNormal3f(cos(angle), sin(angle), 0.0);
	glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
	width * 0.5);
	glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
	-width * 0.5);
	u = r1 * cos(angle + 3 * da) - r2 * cos(angle + 2 * da);
	v = r1 * sin(angle + 3 * da) - r2 * sin(angle + 2 * da);
	glNormal3f(v, -u, 0.0);
	glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
	width * 0.5);
	glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
	-width * 0.5);
	glNormal3f(cos(angle), sin(angle), 0.0);
	}

	glVertex3f(r1 * cos(0), r1 * sin(0), width * 0.5);
	glVertex3f(r1 * cos(0), r1 * sin(0), -width * 0.5);

	glEnd();

	glShadeModel(GL_SMOOTH);

	/* draw inside radius cylinder */
	glBegin(GL_QUAD_STRIP);
	for (i = 0; i <= teeth; i++) {
	angle = i * 2.0 * M_PI / teeth;
	glNormal3f(-cos(angle), -sin(angle), 0.0);
	glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
	glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
	}
	glEnd();
	}


	static void
	draw(void)
	{
	glClear(GL_COLOR_BUFFER_BIT \| GL_DEPTH_BUFFER_BIT);

	glPushMatrix();
	glRotatef(view_rotx, 1.0, 0.0, 0.0);
	glRotatef(view_roty, 0.0, 1.0, 0.0);
	glRotatef(view_rotz, 0.0, 0.0, 1.0);

	glPushMatrix();
	glTranslatef(-3.0, -2.0, 0.0);
	glRotatef(angle, 0.0, 0.0, 1.0);
	glCallList(gear1);
	glPopMatrix();

	glPushMatrix();
	glTranslatef(3.1, -2.0, 0.0);
	glRotatef(-2.0 * angle - 9.0, 0.0, 0.0, 1.0);
	glCallList(gear2);
	glPopMatrix();

	glPushMatrix();
	glTranslatef(-3.1, 4.2, 0.0);
	glRotatef(-2.0 * angle - 25.0, 0.0, 0.0, 1.0);
	glCallList(gear3);
	glPopMatrix();

	glPopMatrix();
	}


	/* new window size or exposure */
	static void
	reshape(int width, int height)
	{
	GLfloat h = (GLfloat) height / (GLfloat) width;

	glViewport(0, 0, (GLint) width, (GLint) height);

	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glFrustum(-1.0, 1.0, -h, h, 5.0, 60.0);

	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	glTranslatef(0.0, 0.0, -40.0);
	}



	static void
	init(void)
	{
	static GLfloat pos[4] = { 5.0, 5.0, 10.0, 0.0 };
	static GLfloat red[4] = { 0.8, 0.1, 0.0, 1.0 };
	static GLfloat green[4] = { 0.0, 0.8, 0.2, 1.0 };
	static GLfloat blue[4] = { 0.2, 0.2, 1.0, 1.0 };

	glLightfv(GL_LIGHT0, GL_POSITION, pos);
	glEnable(GL_CULL_FACE);
	glEnable(GL_LIGHTING);
	glEnable(GL_LIGHT0);
	glEnable(GL_DEPTH_TEST);

	/* make the gears */
	gear1 = glGenLists(1);
	glNewList(gear1, GL_COMPILE);
	glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, red);
	gear(1.0, 4.0, 1.0, 20, 0.7);
	glEndList();

	gear2 = glGenLists(1);
	glNewList(gear2, GL_COMPILE);
	glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, green);
	gear(0.5, 2.0, 2.0, 10, 0.7);
	glEndList();

	gear3 = glGenLists(1);
	glNewList(gear3, GL_COMPILE);
	glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, blue);
	gear(1.3, 2.0, 0.5, 10, 0.7);
	glEndList();

	glEnable(GL_NORMALIZE);
	}




	static void run_gears(EGLDisplay dpy, EGLSurface surf, int ttr)
	{
	double st = current_time();
	double ct = st;
	int frames = 0;
	GLfloat seconds, fps;

	while (ct - st < ttr)
	{
	double tt = current_time();
	double dt = tt - ct;
	ct = tt;

	/* advance rotation for next frame */
	angle += 70.0 * dt; /* 70 degrees per second */
	if (angle > 3600.0)
	angle -= 3600.0;

	draw();

	eglSwapBuffers(dpy, surf);


	frames++;
	}

	seconds = ct - st;
	fps = frames / seconds;
	printf("%d frames in %3.1f seconds = %6.3f FPS\n", frames, seconds, fps);

	}


	int
	main(int argc, char *argv[])
	{
	int maj, min;
	EGLContext ctx;
	EGLSurface screen_surf;
	EGLConfig configs[MAX_CONFIGS];
	EGLint numConfigs, i;
	EGLBoolean b;
	EGLDisplay d;
	EGLint screenAttribs[10];
	EGLModeMESA mode[MAX_MODES];
	EGLScreenMESA screen;
	EGLint count, chosenMode;
	GLboolean printInfo = GL_FALSE;
	EGLint width = 0, height = 0;

	/* parse cmd line args */
	for (i = 1; i < argc; i++)
	{
	if (strcmp(argv[i], "-info") == 0)
	{
	printInfo = GL_TRUE;
	}
	else
	printf("Warning: unknown parameter: %s\n", argv[i]);
	}

	/* DBR : Create EGL context/surface etc */
	d = eglGetDisplay(EGL_DEFAULT_DISPLAY);
	assert(d);

	if (!eglInitialize(d, &maj, &min)) {
	printf("eglgears: eglInitialize failed\n");
	exit(1);
	}

	printf("eglgears: EGL version = %d.%d\n", maj, min);
	printf("eglgears: EGL_VENDOR = %s\n", eglQueryString(d, EGL_VENDOR));

	/* XXX use ChooseConfig */
	eglGetConfigs(d, configs, MAX_CONFIGS, &numConfigs);
	eglGetScreensMESA(d, &screen, 1, &count);

	if (!eglGetModesMESA(d, screen, mode, MAX_MODES, &count) \|\| count == 0) {
	printf("eglgears: eglGetModesMESA failed!\n");
	return 0;
	}

	/* Print list of modes, and find the one to use */
	printf("eglgears: Found %d modes:\n", count);
	for (i = 0; i < count; i++) {
	EGLint w, h;
	eglGetModeAttribMESA(d, mode[i], EGL_WIDTH, &w);
	eglGetModeAttribMESA(d, mode[i], EGL_HEIGHT, &h);
	printf("%3d: %d x %d\n", i, w, h);
	if (w > width && h > height) {
	width = w;
	height = h;
	chosenMode = i;
	}
	}
	printf("eglgears: Using screen mode/size %d: %d x %d\n", chosenMode, width, height);

	ctx = eglCreateContext(d, configs[0], EGL_NO_CONTEXT, NULL);
	if (ctx == EGL_NO_CONTEXT) {
	printf("eglgears: failed to create context\n");
	return 0;
	}

	/* build up screenAttribs array */
	i = 0;
	screenAttribs[i++] = EGL_WIDTH;
	screenAttribs[i++] = width;
	screenAttribs[i++] = EGL_HEIGHT;
	screenAttribs[i++] = height;
	screenAttribs[i++] = EGL_NONE;

	screen_surf = eglCreateScreenSurfaceMESA(d, configs[0], screenAttribs);
	if (screen_surf == EGL_NO_SURFACE) {
	printf("eglgears: failed to create screen surface\n");
	return 0;
	}

	b = eglShowScreenSurfaceMESA(d, screen, screen_surf, mode[chosenMode]);
	if (!b) {
	printf("eglgears: show surface failed\n");
	return 0;
	}

	b = eglMakeCurrent(d, screen_surf, screen_surf, ctx);
	if (!b) {
	printf("eglgears: make current failed\n");
	return 0;
	}

	if (printInfo)
	{
	printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
	printf("GL_VERSION = %s\n", (char *) glGetString(GL_VERSION));
	printf("GL_VENDOR = %s\n", (char *) glGetString(GL_VENDOR));
	printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
	}

	init();
	reshape(width, height);

	glDrawBuffer( GL_BACK );

	run_gears(d, screen_surf, 5.0);

	eglDestroySurface(d, screen_surf);
	eglDestroyContext(d, ctx);
	eglTerminate(d);

	return 0;
	}