用opengl做的water

#include <math.h> #include <stdio.h> #include <stdlib.h> #include <GL/glut.h> #include "texture.h" #ifdef _WIN32 #define expf(x) ((float)exp((x))) #define sinf(x) ((float)sin((x))) #define M_PI 3.14159265 #endif static int rgb; static int translate = 1; static int mesh = 1; static float ttrans[2]; static float transx, transy, rotx, roty; static float amplitude = 0.03; static float freq = 5.0f; static float phase = .00003; static int ox = -1, oy = -1; static int mot; #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 ffunc(void) { freq *= 2.f; } void Ffunc(void) { freq /= 2.f; } void mfunc(void) { mesh ^= 1; } void wire(void) { static int w; if (w ^= 1) { glPolygonMode(GL_FRONT_AND_BACK, GL_LINE); } else { glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); } } void light(void) { static int l; if (l ^= 1) glEnable(GL_LIGHTING); else glDisable(GL_LIGHTING); } void up(void) { amplitude += .01; } void down(void) { amplitude -= .01; } void left(void) { phase -= .00001; } void right(void) { phase += .00001; } void animate(void) { ttrans[0] += .005f; if (ttrans[0] == 1.0f) ttrans[0] = 0.0f; ttrans[1] -= .0025f; if (ttrans[1] <= 0.0f) ttrans[1] = 1.0f; glutPostRedisplay(); } void xfunc(void) { static state = 1; glutIdleFunc((state ^= 1) ? animate : NULL); } void help(void) { printf("Usage: water [image]\n"); printf("'h' - help\n"); printf("'l' - toggle lighting\n"); printf("'f' - increase frequency\n"); printf("'F' - decrease frequency\n"); printf("'m' - toggle mesh\n"); printf("'w' - toggle wireframe\n"); printf("'x' - toggle water motion\n"); printf("'UP' - increase amplitude\n"); printf("'DOWN' - decrease amplitude\n"); printf("'RIGHT' - increase phase change\n"); printf("'LEFT' - decreae phase change\n"); printf("left mouse - pan\n"); printf("right mouse - rotate\n"); } void init(char *filename) { GLfloat cloud_color[4] = { 1., 1., 1., 0., }; GLfloat fog_color[4], fog_density = 0.05, density, far_cull; unsigned *image; int width, height, components; // 从文件中获取纹理数据 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 loaded\n", width, height); } if (components < 3) rgb = 0; } // 由程序自动生成纹理数据 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; } } // 纹理参数的定义 glPixelStorei(GL_UNPACK_ALIGNMENT, 1); glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE); glTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, cloud_color); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); glTexImage2D(GL_TEXTURE_2D, 0, components, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, image); glEnable(GL_TEXTURE_2D); // 使用雾 glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(50.,1.,.1,far_cull = 10.); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glTranslatef(0.,0.,-5.5); density = 1.- expf(-5.5 * fog_density * fog_density * far_cull * far_cull); #define MAX(a,b) ((a) > (b) ? (a) : (b)) #define MIN(a,b) ((a) < (b) ? (a) : (b)) density = MAX(MIN(density, 1.), 0.); fog_color[0] = .23 + density *.57; fog_color[1] = .35 + density *.45; fog_color[2] = .78 + density *.22; glClearColor(fog_color[0], fog_color[1], fog_color[2], 1.f); glFogi(GL_FOG_MODE, GL_EXP2); glFogf(GL_FOG_DENSITY, fog_density); glFogfv(GL_FOG_COLOR, fog_color); if (fog_density > 0) glEnable(GL_FOG); } void draw_mesh(void) { if (mesh) // 以四边形模式进行绘制 { glBegin(GL_QUADS); glTexCoord2f(0, 0); glVertex3f(-1.f, 0.f, -1.f); glTexCoord2f(0, 1); glVertex3f(-1.f, 0.f, 1.f); glTexCoord2f(1, 1); glVertex3f( 1.f, 0.f, 1.f); glTexCoord2f(1, 0); glVertex3f( 1.f, 0.f, -1.f); glEnd(); } else // 以多个三角形面片的形式进行绘制 { #define MESH 32 int i, j; static float off; float d = 1.f/MESH; for(i = 0; i < MESH; i++) { glBegin(GL_TRIANGLE_STRIP); for(j = 0; j < MESH; j++) { float s = (float)j*d; float t = (float)i*d; float x = -1.0 + 2.f*s; float z = -1.0 + 2.f*t; float y = amplitude*sinf(freq*2.f*M_PI*t+off); glTexCoord2f(s, t); glVertex3f(x, y, z); s += d; t += d; x = -1.0 + 2.f*s; z = -1.0 + 2.f*t; y = amplitude*sinf(freq*2.f*M_PI*t+off); glTexCoord2f(s, t); glVertex3f(x, y, z); off += phase; } glEnd(); } } } void display(void) { glClear(GL_COLOR_BUFFER_BIT); glPushMatrix(); glTranslatef(transx, transy, 0.f); glRotatef(rotx, 0., 1., 0.); glRotatef(roty, 1., 0., 0.); glScalef(10,1,10); if (!rgb) glColor3f(.31, .41, .97); else glColor3f(1.f,1.f,1.f); glTranslatef(0.f,-1.f,0.f); glMatrixMode(GL_TEXTURE); glPushMatrix(); glTranslatef(ttrans[0], ttrans[1], 0.); glScalef(10.f, 10.f,1.f); draw_mesh(); glPopMatrix(); glMatrixMode(GL_MODELVIEW); glPopMatrix(); glutSwapBuffers(); } void reshape(int w, int h) { glViewport(0, 0, w, h); } void key(unsigned char key, int x, int y) { switch(key) { case 'l': light(); break; case 'f': ffunc(); break; case 'F': Ffunc(); break; case 'm': mfunc(); break; case 'w': wire(); break; case 'x': xfunc(); break; case 'h': help(); break; case '\033': exit(EXIT_SUCCESS); break; default: break; } glutPostRedisplay(); } 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; } } void visible(int state) { if (state == GLUT_VISIBLE) glutIdleFunc(animate); else glutIdleFunc(NULL); } int main(int argc, char** argv) { glutInitDisplayMode(GLUT_RGBA|GLUT_DOUBLE); glutInitWindowSize(400, 300); glutInit(&argc, argv); glutCreateWindow(argv[0]); init(argc == 1 ? "water1.bw" : argv[1]); g