mirror of
https://github.com/glfw/glfw.git
synced 2024-11-26 20:11:58 +00:00
379 lines
10 KiB
C
379 lines
10 KiB
C
/*
|
|
* 3-D gear wheels. This program is in the public domain.
|
|
*
|
|
* Command line options:
|
|
* -info print GL implementation information
|
|
* -exit automatically exit after 30 seconds
|
|
*
|
|
*
|
|
* Brian Paul
|
|
*
|
|
*
|
|
* Marcus Geelnard:
|
|
* - Conversion to GLFW
|
|
* - Time based rendering (frame rate independent)
|
|
* - Slightly modified camera that should work better for stereo viewing
|
|
*
|
|
*
|
|
* Camilla Berglund:
|
|
* - Removed FPS counter (this is not a benchmark)
|
|
* - Added a few comments
|
|
* - Enabled vsync
|
|
*/
|
|
|
|
|
|
#include <math.h>
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <GL/glfw3.h>
|
|
|
|
#ifndef M_PI
|
|
#define M_PI 3.141592654
|
|
#endif
|
|
|
|
/* The program exits when this is zero.
|
|
*/
|
|
static int running = 1;
|
|
|
|
/* If non-zero, the program exits after that many seconds
|
|
*/
|
|
static int autoexit = 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.f;
|
|
r2 = outer_radius + tooth_depth / 2.f;
|
|
|
|
da = 2.f * (float) M_PI / teeth / 4.f;
|
|
|
|
glShadeModel(GL_FLAT);
|
|
|
|
glNormal3f(0.f, 0.f, 1.f);
|
|
|
|
/* draw front face */
|
|
glBegin(GL_QUAD_STRIP);
|
|
for (i = 0; i <= teeth; i++) {
|
|
angle = i * 2.f * (float) M_PI / teeth;
|
|
glVertex3f(r0 * (float) cos(angle), r0 * (float) sin(angle), width * 0.5f);
|
|
glVertex3f(r1 * (float) cos(angle), r1 * (float) sin(angle), width * 0.5f);
|
|
if (i < teeth) {
|
|
glVertex3f(r0 * (float) cos(angle), r0 * (float) sin(angle), width * 0.5f);
|
|
glVertex3f(r1 * (float) cos(angle + 3 * da), r1 * (float) sin(angle + 3 * da), width * 0.5f);
|
|
}
|
|
}
|
|
glEnd();
|
|
|
|
/* draw front sides of teeth */
|
|
glBegin(GL_QUADS);
|
|
da = 2.f * (float) M_PI / teeth / 4.f;
|
|
for (i = 0; i < teeth; i++) {
|
|
angle = i * 2.f * (float) M_PI / teeth;
|
|
|
|
glVertex3f(r1 * (float) cos(angle), r1 * (float) sin(angle), width * 0.5f);
|
|
glVertex3f(r2 * (float) cos(angle + da), r2 * (float) sin(angle + da), width * 0.5f);
|
|
glVertex3f(r2 * (float) cos(angle + 2 * da), r2 * (float) sin(angle + 2 * da), width * 0.5f);
|
|
glVertex3f(r1 * (float) cos(angle + 3 * da), r1 * (float) sin(angle + 3 * da), width * 0.5f);
|
|
}
|
|
glEnd();
|
|
|
|
glNormal3f(0.0, 0.0, -1.0);
|
|
|
|
/* draw back face */
|
|
glBegin(GL_QUAD_STRIP);
|
|
for (i = 0; i <= teeth; i++) {
|
|
angle = i * 2.f * (float) M_PI / teeth;
|
|
glVertex3f(r1 * (float) cos(angle), r1 * (float) sin(angle), -width * 0.5f);
|
|
glVertex3f(r0 * (float) cos(angle), r0 * (float) sin(angle), -width * 0.5f);
|
|
if (i < teeth) {
|
|
glVertex3f(r1 * (float) cos(angle + 3 * da), r1 * (float) sin(angle + 3 * da), -width * 0.5f);
|
|
glVertex3f(r0 * (float) cos(angle), r0 * (float) sin(angle), -width * 0.5f);
|
|
}
|
|
}
|
|
glEnd();
|
|
|
|
/* draw back sides of teeth */
|
|
glBegin(GL_QUADS);
|
|
da = 2.f * (float) M_PI / teeth / 4.f;
|
|
for (i = 0; i < teeth; i++) {
|
|
angle = i * 2.f * (float) M_PI / teeth;
|
|
|
|
glVertex3f(r1 * (float) cos(angle + 3 * da), r1 * (float) sin(angle + 3 * da), -width * 0.5f);
|
|
glVertex3f(r2 * (float) cos(angle + 2 * da), r2 * (float) sin(angle + 2 * da), -width * 0.5f);
|
|
glVertex3f(r2 * (float) cos(angle + da), r2 * (float) sin(angle + da), -width * 0.5f);
|
|
glVertex3f(r1 * (float) cos(angle), r1 * (float) sin(angle), -width * 0.5f);
|
|
}
|
|
glEnd();
|
|
|
|
/* draw outward faces of teeth */
|
|
glBegin(GL_QUAD_STRIP);
|
|
for (i = 0; i < teeth; i++) {
|
|
angle = i * 2.f * (float) M_PI / teeth;
|
|
|
|
glVertex3f(r1 * (float) cos(angle), r1 * (float) sin(angle), width * 0.5f);
|
|
glVertex3f(r1 * (float) cos(angle), r1 * (float) sin(angle), -width * 0.5f);
|
|
u = r2 * (float) cos(angle + da) - r1 * (float) cos(angle);
|
|
v = r2 * (float) sin(angle + da) - r1 * (float) sin(angle);
|
|
len = (float) sqrt(u * u + v * v);
|
|
u /= len;
|
|
v /= len;
|
|
glNormal3f(v, -u, 0.0);
|
|
glVertex3f(r2 * (float) cos(angle + da), r2 * (float) sin(angle + da), width * 0.5f);
|
|
glVertex3f(r2 * (float) cos(angle + da), r2 * (float) sin(angle + da), -width * 0.5f);
|
|
glNormal3f((float) cos(angle), (float) sin(angle), 0.f);
|
|
glVertex3f(r2 * (float) cos(angle + 2 * da), r2 * (float) sin(angle + 2 * da), width * 0.5f);
|
|
glVertex3f(r2 * (float) cos(angle + 2 * da), r2 * (float) sin(angle + 2 * da), -width * 0.5f);
|
|
u = r1 * (float) cos(angle + 3 * da) - r2 * (float) cos(angle + 2 * da);
|
|
v = r1 * (float) sin(angle + 3 * da) - r2 * (float) sin(angle + 2 * da);
|
|
glNormal3f(v, -u, 0.f);
|
|
glVertex3f(r1 * (float) cos(angle + 3 * da), r1 * (float) sin(angle + 3 * da), width * 0.5f);
|
|
glVertex3f(r1 * (float) cos(angle + 3 * da), r1 * (float) sin(angle + 3 * da), -width * 0.5f);
|
|
glNormal3f((float) cos(angle), (float) sin(angle), 0.f);
|
|
}
|
|
|
|
glVertex3f(r1 * (float) cos(0), r1 * (float) sin(0), width * 0.5f);
|
|
glVertex3f(r1 * (float) cos(0), r1 * (float) sin(0), -width * 0.5f);
|
|
|
|
glEnd();
|
|
|
|
glShadeModel(GL_SMOOTH);
|
|
|
|
/* draw inside radius cylinder */
|
|
glBegin(GL_QUAD_STRIP);
|
|
for (i = 0; i <= teeth; i++) {
|
|
angle = i * 2.f * (float) M_PI / teeth;
|
|
glNormal3f(-(float) cos(angle), -(float) sin(angle), 0.f);
|
|
glVertex3f(r0 * (float) cos(angle), r0 * (float) sin(angle), -width * 0.5f);
|
|
glVertex3f(r0 * (float) cos(angle), r0 * (float) sin(angle), width * 0.5f);
|
|
}
|
|
glEnd();
|
|
|
|
}
|
|
|
|
|
|
static GLfloat view_rotx = 20.f, view_roty = 30.f, view_rotz = 0.f;
|
|
static GLint gear1, gear2, gear3;
|
|
static GLfloat angle = 0.f;
|
|
|
|
/* OpenGL draw function & timing */
|
|
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(3.1f, -2.f, 0.f);
|
|
glRotatef(-2.f * angle - 9.f, 0.f, 0.f, 1.f);
|
|
glCallList(gear2);
|
|
glPopMatrix();
|
|
|
|
glPushMatrix();
|
|
glTranslatef(-3.1f, 4.2f, 0.f);
|
|
glRotatef(-2.f * angle - 25.f, 0.f, 0.f, 1.f);
|
|
glCallList(gear3);
|
|
glPopMatrix();
|
|
|
|
glPopMatrix();
|
|
}
|
|
|
|
|
|
/* update animation parameters */
|
|
static void animate(void)
|
|
{
|
|
angle = 100.f * (float) glfwGetTime();
|
|
}
|
|
|
|
|
|
/* change view angle, exit upon ESC */
|
|
void key( GLFWwindow window, int k, int action )
|
|
{
|
|
if( action != GLFW_PRESS ) return;
|
|
|
|
switch (k) {
|
|
case GLFW_KEY_Z:
|
|
if( glfwGetKey( window, GLFW_KEY_LEFT_SHIFT ) )
|
|
view_rotz -= 5.0;
|
|
else
|
|
view_rotz += 5.0;
|
|
break;
|
|
case GLFW_KEY_ESCAPE:
|
|
running = 0;
|
|
break;
|
|
case GLFW_KEY_UP:
|
|
view_rotx += 5.0;
|
|
break;
|
|
case GLFW_KEY_DOWN:
|
|
view_rotx -= 5.0;
|
|
break;
|
|
case GLFW_KEY_LEFT:
|
|
view_roty += 5.0;
|
|
break;
|
|
case GLFW_KEY_RIGHT:
|
|
view_roty -= 5.0;
|
|
break;
|
|
default:
|
|
return;
|
|
}
|
|
}
|
|
|
|
|
|
/* new window size */
|
|
void reshape( GLFWwindow window, int width, int height )
|
|
{
|
|
GLfloat h = (GLfloat) height / (GLfloat) width;
|
|
GLfloat xmax, znear, zfar;
|
|
|
|
znear = 5.0f;
|
|
zfar = 30.0f;
|
|
xmax = znear * 0.5f;
|
|
|
|
glViewport( 0, 0, (GLint) width, (GLint) height );
|
|
glMatrixMode( GL_PROJECTION );
|
|
glLoadIdentity();
|
|
glFrustum( -xmax, xmax, -xmax*h, xmax*h, znear, zfar );
|
|
glMatrixMode( GL_MODELVIEW );
|
|
glLoadIdentity();
|
|
glTranslatef( 0.0, 0.0, -20.0 );
|
|
}
|
|
|
|
|
|
/* program & OpenGL initialization */
|
|
static void init(int argc, char *argv[])
|
|
{
|
|
static GLfloat pos[4] = {5.f, 5.f, 10.f, 0.f};
|
|
static GLfloat red[4] = {0.8f, 0.1f, 0.f, 1.f};
|
|
static GLfloat green[4] = {0.f, 0.8f, 0.2f, 1.f};
|
|
static GLfloat blue[4] = {0.2f, 0.2f, 1.f, 1.f};
|
|
GLint i;
|
|
|
|
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.f, 4.f, 1.f, 20, 0.7f);
|
|
glEndList();
|
|
|
|
gear2 = glGenLists(1);
|
|
glNewList(gear2, GL_COMPILE);
|
|
glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, green);
|
|
gear(0.5f, 2.f, 2.f, 10, 0.7f);
|
|
glEndList();
|
|
|
|
gear3 = glGenLists(1);
|
|
glNewList(gear3, GL_COMPILE);
|
|
glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, blue);
|
|
gear(1.3f, 2.f, 0.5f, 10, 0.7f);
|
|
glEndList();
|
|
|
|
glEnable(GL_NORMALIZE);
|
|
|
|
for ( i=1; i<argc; i++ ) {
|
|
if (strcmp(argv[i], "-info")==0) {
|
|
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));
|
|
}
|
|
else if ( strcmp(argv[i], "-exit")==0) {
|
|
autoexit = 30;
|
|
printf("Auto Exit after %i seconds.\n", autoexit );
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/* program entry */
|
|
int main(int argc, char *argv[])
|
|
{
|
|
GLFWwindow window;
|
|
|
|
if( !glfwInit(NULL) )
|
|
{
|
|
fprintf( stderr, "Failed to initialize GLFW\n" );
|
|
exit( EXIT_FAILURE );
|
|
}
|
|
|
|
glfwOpenWindowHint(GLFW_DEPTH_BITS, 16);
|
|
|
|
window = glfwOpenWindow( 300, 300, GLFW_WINDOWED, "Gears", NULL );
|
|
if (!window)
|
|
{
|
|
fprintf( stderr, "Failed to open GLFW window\n" );
|
|
glfwTerminate();
|
|
exit( EXIT_FAILURE );
|
|
}
|
|
|
|
glfwSetInputMode( window, GLFW_KEY_REPEAT, GL_TRUE );
|
|
glfwSwapInterval( 1 );
|
|
|
|
// Parse command-line options
|
|
init(argc, argv);
|
|
|
|
// Set callback functions
|
|
glfwSetWindowSizeCallback( reshape );
|
|
glfwSetKeyCallback( key );
|
|
|
|
// Main loop
|
|
while( running )
|
|
{
|
|
// Draw gears
|
|
draw();
|
|
|
|
// Update animation
|
|
animate();
|
|
|
|
// Swap buffers
|
|
glfwSwapBuffers();
|
|
glfwPollEvents();
|
|
|
|
// Was the window closed?
|
|
if( !glfwIsWindow( window ) )
|
|
{
|
|
running = 0;
|
|
}
|
|
}
|
|
|
|
// Terminate GLFW
|
|
glfwTerminate();
|
|
|
|
// Exit program
|
|
exit( EXIT_SUCCESS );
|
|
}
|
|
|