explode.c
上传用户:xk288cn
上传日期:2007-05-28
资源大小:4876k
文件大小:10k
- #include <math.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <GL/glut.h>
- #include "texture.h"
- #ifndef __sgi
- /* Most math.h's do not define float versions of the trig functions. */
- #define sinf sin
- #define cosf cos
- #define atan2f atan2
- #endif
- /* Some <math.h> files do not define M_PI... */
- #ifndef M_PI
- #define M_PI 3.14159265358979323846
- #endif
- static int texture = 1;
- static float rot = 0;
- static float opacity = 1.0;
- static float intensity = 1.0;
- static float size = .001, delta = 0;
- static float scale = 1.;
- static float transx, transy, rotx, roty;
- static int ox = -1, oy = -1;
- static int mot = 0;
- #define PAN 1
- #define ROT 2
- void
- pan(int x, int y) {
- transx += (x-ox)/500.;
- transy -= (y-oy)/500.;
- ox = x; oy = y;
- glutPostRedisplay();
- }
- void
- rotate(int x, int y) {
- rotx += x-ox;
- if (rotx > 360.) rotx -= 360.;
- else if (rotx < -360.) rotx += 360.;
- roty += y-oy;
- if (roty > 360.) roty -= 360.;
- else if (roty < -360.) roty += 360.;
- ox = x; oy = y;
- glutPostRedisplay();
- }
- void
- motion(int x, int y) {
- if (mot == PAN) pan(x, y);
- else if (mot == ROT) rotate(x,y);
- }
- void
- mouse(int button, int state, int x, int y) {
- if(state == GLUT_DOWN) {
- switch(button) {
- case GLUT_LEFT_BUTTON:
- mot = PAN;
- motion(ox = x, oy = y);
- break;
- case GLUT_RIGHT_BUTTON:
- mot = ROT;
- motion(ox = x, oy = y);
- break;
- case GLUT_MIDDLE_BUTTON:
- break;
- }
- } else if (state == GLUT_UP) {
- mot = 0;
- }
- }
- void afunc(void) {
- static int state;
- if (state ^= 1) {
- glAlphaFunc(GL_GREATER, .01);
- glEnable(GL_ALPHA_TEST);
- } else {
- glDisable(GL_ALPHA_TEST);
- }
- }
- void bfunc(void) {
- static int state;
- if (state ^= 1) {
- glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
- glEnable(GL_BLEND);
- } else {
- glDisable(GL_BLEND);
- }
- }
- void tfunc(void) {
- texture ^= 1;
- }
- void up(void) { scale += .1; }
- void down(void) { scale -= .1; }
- void left(void) { intensity -= .05f; if (intensity < 0.f) intensity = 0.0f; }
- void right(void) { intensity += .05f; if (intensity > 1.f) intensity = 1.0f; }
- void help(void) {
- printf("Usage: explode [image]n");
- printf("'h' - helpn");
- printf("'a' - toggle alpha testn");
- printf("'b' - toggle blendn");
- printf("'t' - toggle texturingn");
- printf("'UP' - scale upn");
- printf("'DOWN' - scale downn");
- printf("'LEFT' - darkenn");
- printf("'RIGHT' - brightenn");
- printf("left mouse - pann");
- printf("right mouse - rotaten");
- }
- void init(char *filename) {
- static unsigned *image;
- static int width, height, components;
- if (filename) {
- image = read_texture(filename, &width, &height, &components);
- if (image == NULL) {
- fprintf(stderr, "Error: Can't load image file "%s".n",
- filename);
- exit(EXIT_FAILURE);
- } else {
- printf("%d x %d image loadedn", width, height);
- }
- if (components != 2 && components != 4) {
- printf("must be an RGBA or LA imagen");
- exit(EXIT_FAILURE);
- }
- } else {
- int i, j;
- unsigned char *img;
- components = 4; width = height = 512;
- image = (unsigned *) malloc(width*height*sizeof(unsigned));
- img = (unsigned char *)image;
- for (j = 0; j < height; j++)
- for (i = 0; i < width; i++) {
- int w2 = width/2, h2 = height/2;
- if (i & 32)
- img[4*(i+j*width)+0] = 0xff;
- else
- img[4*(i+j*width)+1] = 0xff;
- if (j&32)
- img[4*(i+j*width)+2] = 0xff;
- if ((i-w2)*(i-w2) + (j-h2)*(j-h2) > 64*64 &&
- (i-w2)*(i-w2) + (j-h2)*(j-h2) < 300*300) img[4*(i+j*width)+3] = 0xff;
- }
- }
- glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
- glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
- glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
- glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
- glTexImage2D(GL_TEXTURE_2D, 0, components, width,
- height, 0, GL_RGBA, GL_UNSIGNED_BYTE,
- image);
- glEnable(GL_TEXTURE_2D);
- glMatrixMode(GL_PROJECTION);
- glLoadIdentity();
- gluPerspective(50.,1.,.1,20.);
- glMatrixMode(GL_MODELVIEW);
- glLoadIdentity();
- glTranslatef(0.,0.,-5.5);
- glClearColor(.25f, .25f, .75f, .25f);
- glAlphaFunc(GL_GREATER, 0.016);
- glEnable(GL_ALPHA_TEST);
- glEnable(GL_BLEND);
- glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
- glEnable(GL_DEPTH_TEST);
- glEnable(GL_LIGHT0);
- glEnable(GL_COLOR_MATERIAL);
- glEnable(GL_NORMALIZE);
- }
- void
- animate(void) {
- if (delta > 10) {
- delta = 0.f;
- size = 0.f;
- opacity = 1.f;
- rot = 0.f;
- }
- size += .08f;
- delta += .07f;
- rot += .9f;
- opacity -= .005f;
- glutPostRedisplay();
- }
- void
- cube(void) {
- glBegin(GL_QUADS);
- glNormal3f(0.f, 0.f, -1.f);
- glTexCoord2f(0.0, 0.0); glVertex3f(-1.0, -1.0, -1.0);
- glTexCoord2f(1.0, 0.0); glVertex3f( 1.0, -1.0, -1.0);
- glTexCoord2f(1.0, 1.0); glVertex3f( 1.0, 1.0, -1.0);
- glTexCoord2f(0.0, 1.0); glVertex3f(-1.0, 1.0, -1.0);
- glNormal3f(0.f, 0.f, 1.f);
- glTexCoord2f(0.0, 0.0); glVertex3f(-1.0, -1.0, 1.0);
- glTexCoord2f(1.0, 0.0); glVertex3f( 1.0, -1.0, 1.0);
- glTexCoord2f(1.0, 1.0); glVertex3f( 1.0, 1.0, 1.0);
- glTexCoord2f(0.0, 1.0); glVertex3f(-1.0, 1.0, 1.0);
- glNormal3f(0.f, 1.f, 0.f);
- glTexCoord2f(0.0, 0.0); glVertex3f(-1.0, 1.0, -1.0);
- glTexCoord2f(1.0, 0.0); glVertex3f( 1.0, 1.0, -1.0);
- glTexCoord2f(1.0, 1.0); glVertex3f( 1.0, 1.0, 1.0);
- glTexCoord2f(0.0, 1.0); glVertex3f(-1.0, 1.0, 1.0);
- glNormal3f(0.f, -1.f, 0.f);
- glTexCoord2f(0.0, 0.0); glVertex3f(-1.0, -1.0, -1.0);
- glTexCoord2f(1.0, 0.0); glVertex3f( 1.0, -1.0, -1.0);
- glTexCoord2f(1.0, 1.0); glVertex3f( 1.0, -1.0, 1.0);
- glTexCoord2f(0.0, 1.0); glVertex3f(-1.0, -1.0, 1.0);
- glNormal3f( 1.f, 0.f, 0.f);
- glTexCoord2f(0.0, 0.0); glVertex3f( 1.0, -1.0, -1.0);
- glTexCoord2f(1.0, 0.0); glVertex3f( 1.0, 1.0, -1.0);
- glTexCoord2f(1.0, 1.0); glVertex3f( 1.0, 1.0, 1.0);
- glTexCoord2f(0.0, 1.0); glVertex3f( 1.0, -1.0, 1.0);
- glNormal3f(-1.f, 0.f, 0.f);
- glTexCoord2f(0.0, 0.0); glVertex3f(-1.0, -1.0, -1.0);
- glTexCoord2f(1.0, 0.0); glVertex3f(-1.0, 1.0, -1.0);
- glTexCoord2f(1.0, 1.0); glVertex3f(-1.0, 1.0, 1.0);
- glTexCoord2f(0.0, 1.0); glVertex3f(-1.0, -1.0, 1.0);
- glEnd();
- }
- static void calcMatrix(void);
- void display(void) {
- glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
- glLoadIdentity();
- #define RAD(x) (((x)*M_PI)/180.)
- gluLookAt(-sinf(RAD(rotx))*5.5,transy,cosf(RAD(rotx))*5.5, 0.,0.,0., 0.,1.,0.);
- /* floor */
- glColor4f(0.f,.2f,0.f,1.f);
- glBegin(GL_POLYGON);
- glVertex3f(-4.0, -1.0, -4.0);
- glVertex3f( 4.0, -1.0, -4.0);
- glVertex3f( 4.0, -1.0, 4.0);
- glVertex3f(-4.0, -1.0, 4.0);
- glEnd();
- glEnable(GL_LIGHTING);
- glPushMatrix();
- glColor3f(.3f,.3f,.3f);
- glPushMatrix();
- glTranslatef(-1.f, -1.+.2f, -1.5f);
- glScalef(.2f,.2f, .2f);
- cube();
- glPopMatrix();
- glDisable(GL_LIGHTING);
- glTranslatef(-1.f, -1.f, -1.5f);
- calcMatrix();
- glScalef(size,size,1.);
- if (texture) glEnable(GL_TEXTURE_2D);
- glColor4f(intensity, intensity, intensity, opacity);
- glDepthMask(0);
- glBegin(GL_POLYGON);
- glTexCoord2f(0.0, 0.0); glVertex2f(-1.0, -1.0);
- glTexCoord2f(1.0, 0.0); glVertex2f(1.0, -1.0);
- glTexCoord2f(1.0, 1.0); glVertex2f(1.0, 1.0);
- glTexCoord2f(0.0, 1.0); glVertex2f(-1.0, 1.0);
- glEnd();
- glDepthMask(1);
- glPopMatrix();
- glDisable(GL_TEXTURE_2D);
- glutSwapBuffers();
- }
- void reshape(int w, int h) {
- glViewport(0, 0, w, h);
- }
- /* ARGSUSED1 */
- void
- key(unsigned char key, int x, int y) {
- switch(key) {
- case 'a': afunc(); break;
- case 'b': bfunc(); break;
- case 'h': help(); break;
- case 't': tfunc(); break;
- case ' 33': exit(EXIT_SUCCESS); break;
- default: break;
- }
- glutPostRedisplay();
- }
- /* ARGSUSED1 */
- void
- special(int key, int x, int y) {
- switch(key) {
- case GLUT_KEY_UP: up(); break;
- case GLUT_KEY_DOWN: down(); break;
- case GLUT_KEY_LEFT: left(); break;
- case GLUT_KEY_RIGHT:right(); break;
- }
- }
- int main(int argc, char** argv) {
- glutInitWindowSize(512, 512);
- glutInit(&argc, argv);
- glutInitDisplayMode(GLUT_RGBA|GLUT_DOUBLE|GLUT_DEPTH);
- (void)glutCreateWindow(argv[0]);
- init(argc == 1 ? "../data/explosion.rgba" : argv[1]);
- glutDisplayFunc(display);
- glutKeyboardFunc(key);
- glutSpecialFunc(special);
- glutReshapeFunc(reshape);
- glutMouseFunc(mouse);
- glutMotionFunc(motion);
- glutIdleFunc(animate);
- glutMainLoop();
- return 0;
- }
- void
- printmat(float *m) {
- int i;
- for(i = 0; i < 4; i++) {
- printf("%f %f %f %fn", m[4*i+0], m[4*i+1], m[4*i+2], m[4*i+3]);
- }
- }
- void
- buildRot(float theta, float x, float y, float z, float m[16]) {
- float d = x*x + y*y + z*z;
- float ct = cosf(RAD(theta)), st = sinf(RAD(theta));
- /* normalize */
- if (d > 0) {
- d = 1/d;
- x *= d;
- y *= d;
- z *= d;
- }
- m[ 0] = 1; m[ 1] = 0; m[ 2] = 0; m[ 3] = 0;
- m[ 4] = 0; m[ 5] = 1; m[ 6] = 0; m[ 7] = 0;
- m[ 8] = 0; m[ 9] = 0; m[10] = 1; m[11] = 0;
- m[12] = 0; m[13] = 0; m[14] = 0; m[15] = 1;
- /* R = uu' + cos(theta)*(I-uu') + sin(theta)*S
- *
- * S = 0 -z y u' = (x, y, z)
- * z 0 -x
- * -y x 0
- */
- m[0] = x*x + ct*(1-x*x) + st*0;
- m[4] = x*y + ct*(0-x*y) + st*-z;
- m[8] = x*z + ct*(0-x*z) + st*y;
- m[1] = y*x + ct*(0-y*x) + st*z;
- m[5] = y*y + ct*(1-y*y) + st*0;
- m[9] = y*z + ct*(0-y*z) + st*-x;
- m[2] = z*x + ct*(0-z*x) + st*-y;
- m[6] = z*y + ct*(0-z*y) + st*x;
- m[10]= z*z + ct*(1-z*z) + st*0;
- }
- static void
- calcMatrix(void) {
- float mat[16];
- glGetFloatv(GL_MODELVIEW_MATRIX, mat);
- buildRot(-180*atan2f(mat[8], mat[10])/M_PI, 0, 1, 0, mat);
- glMultMatrixf(mat);
- }