/* * this is a translation of a pascal program from * http://home.kabelfoon.nl/~rhordijk/progs.html * which was, in turn, inspired by the work of william latham * * this code should live at http://www.nixfiles.com/src/horn/ */ #include #include #include #include #define PI 3.1415926536 //#define TRIANGLES #define SPHERES //#define BIGSPHERES //#define POINTS //#define LIGHTMAP #ifdef TRIANGLES # define NRPOINTS 80 # define NRLINES 30 #endif #ifdef SPHERES # define NRPOINTS 80 # define NRLINES 30 #endif #ifdef BIGSPHERES # define SPHERES # define NRPOINTS 20 # define NRLINES 5 #endif #ifdef POINTS # define NRPOINTS 250 # define NRLINES 30 #endif #ifdef LIGHTMAP # define NRPOINTS 150 # define NRLINES 20 #endif int screenwidth; int screenheight; #ifdef SPHERES GLUquadricObj *shapes; #endif DWORD t0; void horn(int ribs, double bend, double stack, double twist, double twisttrans, double grow) { int i; for (i = 0; i < ribs; i++) { double t = ((double) i) / ribs; glPushMatrix(); glRotated(bend * t, 1, 0, 0); glTranslated(0, 0, stack * t); glTranslated(twisttrans, 0, 0); glRotated(twist * t, 0, 0, 1); glTranslated(-twisttrans, 0, 0); #ifdef TRIANGLES glBegin(GL_TRIANGLES); glColor4d(0.9,0.8,0.5, 1); glVertex3d(2,2,0); glColor4d(0.9,0.8,0.5,0.0); glVertex3d(0,2,0); glVertex3d(2,0,0); glEnd(); #endif #ifdef BIGSPHERES gluQuadricDrawStyle(shapes, GLU_FILL); gluQuadricNormals(shapes, GLU_SMOOTH); gluSphere(shapes, 7 * exp(i * log(grow) / ribs), 20, 10); #else #ifdef SPHERES gluQuadricDrawStyle(shapes, GLU_FILL); gluQuadricNormals(shapes, GLU_SMOOTH); // gluSphere(shapes, pow(grow, (1.0 * i) / ribs), 5, 5); gluSphere(shapes, exp(i * log(grow) / ribs), 6, 4); #endif #endif #ifdef LIGHTMAP glBegin(GL_POINTS); glVertex3d(0,0,0); glEnd(); #endif #ifdef POINTS glBegin(GL_POINTS); glVertex3d(0,0,0); glEnd(); #endif glPopMatrix(); } } void ResizeGL(int width, int height) { screenwidth = width; screenheight = height; glViewport(0 , 0, width, height); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(30, ((double) width) / height, 100, 300); } void horn_initgl() { static GLfloat glfLightPosition[] = { 100.0, 100.0, 100.0, 0.0 }; static GLfloat glfFog[] = { 0.0, 0.0, 0.3, 1.0 }; static GLfloat DiffuseLightColor[] = { 1, 0.8, 0.4, 1.0 }; #ifdef LIGHTMAP int i, j; double x, y, r, d; byte texbuf[4096]; #endif glEnable(GL_DEPTH_TEST); glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); glEnable(GL_BLEND); #ifdef SPHERES glEnable(GL_CULL_FACE); glCullFace(GL_BACK); #endif #ifdef SPHERES glLightfv(GL_LIGHT0, GL_POSITION, glfLightPosition); glEnable(GL_LIGHTING); glEnable(GL_LIGHT0); glLightfv(GL_LIGHT0, GL_DIFFUSE , DiffuseLightColor); #endif #ifdef POINTS glHint (GL_POINT_SMOOTH_HINT, GL_NICEST); glPointSize(3); glEnable (GL_POINT_SMOOTH); #endif #ifdef SPHERES #if 0 glFogi (GL_FOG_MODE, GL_LINEAR); glHint (GL_FOG_HINT, GL_NICEST); glFogfv (GL_FOG_COLOR, glfFog); glFogf(GL_FOG_START, 150); glFogf(GL_FOG_END, 550); glEnable(GL_FOG); #endif #endif #ifdef POINTS glFogi (GL_FOG_MODE, GL_LINEAR); glHint (GL_FOG_HINT, GL_NICEST); glFogfv (GL_FOG_COLOR, glfFog); glFogf(GL_FOG_START, 150); glFogf(GL_FOG_END, 250); glEnable(GL_FOG); #endif #ifdef SPHERES shapes = gluNewQuadric(); #endif #ifdef LIGHTMAP r = 32; for (i = 0; i < 64; i++) { for (j = 0; j < 64; j++) { x = fabs(i - 32); y = fabs(j - 32); d = sqrt(x * x + y * y); if (d < r) { d = 1 - (d / r); texbuf[i * 64 + j] = (byte) 255 * d * d; } else { texbuf[i * 64 + j] = 0; } } } gluBuild2DMipmaps(GL_TEXTURE_2D, 1, 64, 64, GL_LUMINANCE, GL_UNSIGNED_BYTE, texbuf); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); #endif #if 0 #ifdef LIGHTMAP // trick to fullscreen ShowWindow(wnd,SW_MAXIMIZE); PostMessage(wnd,WM_SIZE,0,0); #endif #endif } #ifdef LIGHTMAP void horn_paintgl() { double dt; int i,j, offset; GLfloat fb_buffer[NRPOINTS * NRLINES * 4]; double x,y,w; dt = (GetTickCount() - t0) * 0.001; glDisable(GL_DEPTH_TEST); glFeedbackBuffer(NRPOINTS * NRLINES * 4, GL_3D, fb_buffer); glRenderMode(GL_FEEDBACK); glMatrixMode(GL_MODELVIEW); glPushMatrix(); glLoadIdentity(); gluLookAt( 200, 0, 0, 0, 0, 0, 0, 0, 1); glPushMatrix(); glRotated(90, 0, 1, 0); glRotated(10.0 * dt, 0, 0, 1); for (i = 0; i < NRLINES; i++) { glPushMatrix(); glRotated((360.0 * i) / NRLINES, 0, 0, 1); glRotated(45, 1, 0, 0); glTranslated(0, 0, 2); horn(NRPOINTS, 315 * sin(dt * 0.237), 45 + 20 * sin(dt * 0.133), 1500 * sin(dt * 0.213), 7.5 + 2.5 * sin(dt * 0.173), 1); glPopMatrix(); } glPopMatrix(); glPopMatrix(); glRenderMode(GL_RENDER); glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE); glMatrixMode(GL_PROJECTION); glPushMatrix(); glLoadIdentity(); glMatrixMode(GL_MODELVIEW); glPushMatrix(); glLoadIdentity(); glScalef(2.0 / screenwidth, 2.0 / screenheight, 1.0); glTranslatef(0.5 * -screenwidth, 0.5 * -screenheight, 0.0); glClear(GL_COLOR_BUFFER_BIT); glEnable(GL_TEXTURE_2D); glBlendFunc(GL_ONE, GL_ONE); glEnable(GL_BLEND); glBegin(GL_QUADS); for (j = 0; j < NRPOINTS; j++) { glColor3f((0.25 - 0.15 * j) / NRPOINTS, (0.15 + 0.10 * j) / NRPOINTS, (0.06 + 0.14 * j) / NRPOINTS); for (i = 0; i < NRLINES; i++) { offset = 4 * (i * NRPOINTS + j); x = fb_buffer[offset + 1]; y = fb_buffer[offset + 2]; w = 16; glTexCoord2f(0.0, 0.0); glVertex2f(x - w, y - w); glTexCoord2f(1.0, 0.0); glVertex2f(x + w, y - w); glTexCoord2f(1.0, 1.0); glVertex2f(x + w, y + w); glTexCoord2f(0.0, 1.0); glVertex2f(x - w, y + w); } } glEnd(); glMatrixMode(GL_MODELVIEW); glPopMatrix(); glMatrixMode(GL_PROJECTION); glPopMatrix(); } #else void horn_paintgl() { double dt; int i; // dt = (GetTickCount() - t0) * 0.0000001; dt = (GetTickCount() - t0) * 1e-4; glClearColor(0, 0, 0.3, 0); glClear(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(30, ((double) screenwidth) / screenheight, 100, 300); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); gluLookAt( 200, 00, 0, 0, 0, 0, 0, 0, 1); glPushMatrix(); // glRotated(90, 0, 1, 0); glRotated(10 * dt, 0, 1, 0); glRotated(10 * dt, 0, 0, 1); glColor3d(0.9,0.7,0.5); glNewList(1, GL_COMPILE); horn(NRPOINTS, 315 * sin(dt * 0.237), 50 + 20 * sin(dt * 0.133), 1500 * sin(dt * 0.213), 7.5 + 2.5 * sin(dt * 0.173), 0.6 + 0.1 * sin(dt * 0.317)); glEndList(); for (i = 0; i < NRLINES; i++) { glPushMatrix(); glRotated((360.0 * (double) i) / NRLINES, 0, 0, 1); glRotated(45, 1, 0, 0); glTranslated(0, 0, 2); glCallList(1); glPopMatrix(); } glPopMatrix(); } #endif void CloseGL() { #ifdef SPHERES gluDeleteQuadric(shapes); #endif }