| /* |
| * 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 |
| */ |
| |
| #include <math.h> |
| #include <GL/gl.h> |
| #include <EGL/egl.h> |
| |
| #include "eglut.h" |
| |
| #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; |
| |
| /* |
| * |
| * 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(); |
| } |
| |
| |
| static void |
| idle(void) |
| { |
| static double t0 = -1.; |
| double dt, t = eglutGet(EGLUT_ELAPSED_TIME) / 1000.0; |
| if (t0 < 0.0) |
| t0 = t; |
| dt = t - t0; |
| t0 = t; |
| |
| angle += 70.0 * dt; /* 70 degrees per second */ |
| angle = fmod(angle, 360.0); /* prevents eventual overflow */ |
| |
| eglutPostRedisplay(); |
| } |
| |
| /* 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); |
| } |
| |
| int |
| main(int argc, char *argv[]) |
| { |
| eglutInitWindowSize(300, 300); |
| eglutInitAPIMask(EGLUT_OPENGL_BIT); |
| eglutInit(argc, argv); |
| |
| eglutCreateWindow("eglgears"); |
| |
| eglutIdleFunc(idle); |
| eglutReshapeFunc(reshape); |
| eglutDisplayFunc(draw); |
| |
| init(); |
| glDrawBuffer(GL_BACK); |
| |
| eglutMainLoop(); |
| |
| return 0; |
| } |