bounce.c
上传用户:xk288cn
上传日期:2007-05-28
资源大小:4876k
文件大小:3k
- /* bounce.c */
- /*
- * Bouncing ball demo.
- *
- * This program is in the public domain
- *
- * Brian Paul
- */
- /* Conversion to GLUT by Mark J. Kilgard */
- #include <math.h>
- #include <stdlib.h>
- #include <GL/glut.h>
- #define COS(X) cos( (X) * 3.14159/180.0 )
- #define SIN(X) sin( (X) * 3.14159/180.0 )
- #define RED 1
- #define WHITE 2
- #define CYAN 3
- GLuint Ball;
- GLenum Mode;
- GLfloat Zrot = 0.0, Zstep = 6.0;
- GLfloat Xpos = 0.0, Ypos = 1.0;
- GLfloat Xvel = 0.2, Yvel = 0.0;
- GLfloat Xmin = -4.0, Xmax = 4.0;
- GLfloat Ymin = -3.8, Ymax = 4.0;
- GLfloat G = -0.1;
- static GLuint
- make_ball(void)
- {
- GLuint list;
- GLfloat a, b;
- GLfloat da = 18.0, db = 18.0;
- GLfloat radius = 1.0;
- GLuint color;
- GLfloat x, y, z;
- list = glGenLists(1);
- glNewList(list, GL_COMPILE);
- color = 0;
- for (a = -90.0; a + da <= 90.0; a += da) {
- glBegin(GL_QUAD_STRIP);
- for (b = 0.0; b <= 360.0; b += db) {
- if (color) {
- glIndexi(RED);
- } else {
- glIndexi(WHITE);
- }
- x = COS(b) * COS(a);
- y = SIN(b) * COS(a);
- z = SIN(a);
- glVertex3f(x, y, z);
- x = radius * COS(b) * COS(a + da);
- y = radius * SIN(b) * COS(a + da);
- z = radius * SIN(a + da);
- glVertex3f(x, y, z);
- color = 1 - color;
- }
- glEnd();
- }
- glEndList();
- return list;
- }
- static void
- reshape(int width, int height)
- {
- glViewport(0, 0, (GLint) width, (GLint) height);
- glMatrixMode(GL_PROJECTION);
- glLoadIdentity();
- glOrtho(-6.0, 6.0, -6.0, 6.0, -6.0, 6.0);
- glMatrixMode(GL_MODELVIEW);
- }
- /* ARGSUSED1 */
- static void
- key(unsigned char k, int x, int y)
- {
- switch (k) {
- case 27: /* Escape */
- exit(0);
- }
- }
- static void
- draw(void)
- {
- GLint i;
- glClear(GL_COLOR_BUFFER_BIT);
- glIndexi(CYAN);
- glBegin(GL_LINES);
- for (i = -5; i <= 5; i++) {
- glVertex2i(i, -5);
- glVertex2i(i, 5);
- }
- for (i = -5; i <= 5; i++) {
- glVertex2i(-5, i);
- glVertex2i(5, i);
- }
- for (i = -5; i <= 5; i++) {
- glVertex2i(i, -5);
- glVertex2f(i * 1.15, -5.9);
- }
- glVertex2f(-5.3, -5.35);
- glVertex2f(5.3, -5.35);
- glVertex2f(-5.75, -5.9);
- glVertex2f(5.75, -5.9);
- glEnd();
- glPushMatrix();
- glTranslatef(Xpos, Ypos, 0.0);
- glScalef(2.0, 2.0, 2.0);
- glRotatef(8.0, 0.0, 0.0, 1.0);
- glRotatef(90.0, 1.0, 0.0, 0.0);
- glRotatef(Zrot, 0.0, 0.0, 1.0);
- glCallList(Ball);
- glPopMatrix();
- glFlush();
- glutSwapBuffers();
- }
- static void
- idle(void)
- {
- static float vel0 = -100.0;
- Zrot += Zstep;
- Xpos += Xvel;
- if (Xpos >= Xmax) {
- Xpos = Xmax;
- Xvel = -Xvel;
- Zstep = -Zstep;
- }
- if (Xpos <= Xmin) {
- Xpos = Xmin;
- Xvel = -Xvel;
- Zstep = -Zstep;
- }
- Ypos += Yvel;
- Yvel += G;
- if (Ypos < Ymin) {
- Ypos = Ymin;
- if (vel0 == -100.0)
- vel0 = fabs(Yvel);
- Yvel = vel0;
- }
- glutPostRedisplay();
- }
- void
- visible(int vis)
- {
- if (vis == GLUT_VISIBLE)
- glutIdleFunc(idle);
- else
- glutIdleFunc(NULL);
- }
- int
- main(int argc, char *argv[])
- {
- glutInit(&argc, argv);
- glutInitDisplayMode(GLUT_INDEX | GLUT_DOUBLE);
- glutCreateWindow("Bounce");
- Ball = make_ball();
- glCullFace(GL_BACK);
- glEnable(GL_CULL_FACE);
- glDisable(GL_DITHER);
- glShadeModel(GL_FLAT);
- glutDisplayFunc(draw);
- glutReshapeFunc(reshape);
- glutVisibilityFunc(visible);
- glutKeyboardFunc(key);
- glutSetColor(RED, 1.0, 0.0, 0.0);
- glutSetColor(WHITE, 1.0, 1.0, 1.0);
- glutSetColor(CYAN, 0.0, 1.0, 1.0);
- glutMainLoop();
- return 0; /* ANSI C requires main to return int. */
- }