/* * GLSL noise demo. * * Michal Krol * 20 February 2006 * * Based on the original demo by: * Stefan Gustavson (stegu@itn.liu.se) 2004, 2005 */ #ifdef WIN32 #include <windows.h> #endif #include <stdio.h> #include <stdlib.h> #include <GL/gl.h> #include <GL/glut.h> #include <GL/glext.h> #ifdef WIN32 #define GETPROCADDRESS(F) wglGetProcAddress(F) #else #define GETPROCADDRESS(F) glutGetProcAddress(F) #endif static GLhandleARB fragShader; static GLhandleARB vertShader; static GLhandleARB program; static GLint uTime; static GLint t0 = 0; static GLint frames = 0; static GLfloat u_time = 0.0f; static PFNGLCREATESHADEROBJECTARBPROC glCreateShaderObjectARB = NULL; static PFNGLSHADERSOURCEARBPROC glShaderSourceARB = NULL; static PFNGLCOMPILESHADERARBPROC glCompileShaderARB = NULL; static PFNGLCREATEPROGRAMOBJECTARBPROC glCreateProgramObjectARB = NULL; static PFNGLATTACHOBJECTARBPROC glAttachObjectARB = NULL; static PFNGLLINKPROGRAMARBPROC glLinkProgramARB = NULL; static PFNGLUSEPROGRAMOBJECTARBPROC glUseProgramObjectARB = NULL; static PFNGLGETUNIFORMLOCATIONARBPROC glGetUniformLocationARB = NULL; static PFNGLUNIFORM1FARBPROC glUniform1fARB = NULL; static void Redisplay (void) { GLint t; glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glUniform1fARB (uTime, 0.5f * u_time); glPushMatrix (); glutSolidSphere (2.0, 20, 10); glPopMatrix (); glutSwapBuffers(); frames++; t = glutGet (GLUT_ELAPSED_TIME); if (t - t0 >= 5000) { GLfloat seconds = (GLfloat) (t - t0) / 1000.0f; GLfloat fps = frames / seconds; printf ("%d frames in %6.3f seconds = %6.3f FPS\n", frames, seconds, fps); fflush(stdout); t0 = t; frames = 0; } } static void Idle (void) { u_time += 0.1f; glutPostRedisplay (); } static void Reshape (int width, int height) { glViewport (0, 0, width, height); glMatrixMode (GL_PROJECTION); glLoadIdentity (); glFrustum (-1.0, 1.0, -1.0, 1.0, 5.0, 25.0); glMatrixMode (GL_MODELVIEW); glLoadIdentity (); glTranslatef (0.0f, 0.0f, -15.0f); } static void Key (unsigned char key, int x, int y) { (void) x; (void) y; switch (key) { case 27: exit(0); break; } glutPostRedisplay (); } static void Init (void) { static const char *fragShaderText = "uniform float time;\n" "varying vec3 position;\n" "void main () {\n" " gl_FragColor = vec4 (vec3 (0.5 + 0.5 * noise1 (vec4 (position, time))), 1.0);\n" "}\n" ; static const char *vertShaderText = "varying vec3 position;\n" "void main () {\n" " gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;\n" " position = 4.0 * gl_Vertex.xyz;\n" "}\n" ; if (!glutExtensionSupported ("GL_ARB_fragment_shader")) { printf ("Sorry, this demo requires GL_ARB_fragment_shader\n"); exit(1); } if (!glutExtensionSupported ("GL_ARB_shader_objects")) { printf ("Sorry, this demo requires GL_ARB_shader_objects\n"); exit(1); } if (!glutExtensionSupported ("GL_ARB_shading_language_100")) { printf ("Sorry, this demo requires GL_ARB_shading_language_100\n"); exit(1); } if (!glutExtensionSupported ("GL_ARB_vertex_shader")) { printf ("Sorry, this demo requires GL_ARB_vertex_shader\n"); exit(1); } glCreateShaderObjectARB = (PFNGLCREATESHADEROBJECTARBPROC) GETPROCADDRESS("glCreateShaderObjectARB"); glShaderSourceARB = (PFNGLSHADERSOURCEARBPROC) GETPROCADDRESS("glShaderSourceARB"); glCompileShaderARB = (PFNGLCOMPILESHADERARBPROC) GETPROCADDRESS("glCompileShaderARB"); glCreateProgramObjectARB = (PFNGLCREATEPROGRAMOBJECTARBPROC) GETPROCADDRESS("glCreateProgramObjectARB"); glAttachObjectARB = (PFNGLATTACHOBJECTARBPROC) GETPROCADDRESS("glAttachObjectARB"); glLinkProgramARB = (PFNGLLINKPROGRAMARBPROC) GETPROCADDRESS ("glLinkProgramARB"); glUseProgramObjectARB = (PFNGLUSEPROGRAMOBJECTARBPROC) GETPROCADDRESS("glUseProgramObjectARB"); glGetUniformLocationARB = (PFNGLGETUNIFORMLOCATIONARBPROC) GETPROCADDRESS("glGetUniformLocationARB"); glUniform1fARB = (PFNGLUNIFORM1FARBPROC) GETPROCADDRESS("glUniform1fARB"); fragShader = glCreateShaderObjectARB (GL_FRAGMENT_SHADER_ARB); glShaderSourceARB (fragShader, 1, &fragShaderText, NULL); glCompileShaderARB (fragShader); vertShader = glCreateShaderObjectARB (GL_VERTEX_SHADER_ARB); glShaderSourceARB (vertShader, 1, &vertShaderText, NULL); glCompileShaderARB (vertShader); program = glCreateProgramObjectARB (); glAttachObjectARB (program, fragShader); glAttachObjectARB (program, vertShader); glLinkProgramARB (program); glUseProgramObjectARB (program); uTime = glGetUniformLocationARB (program, "time"); glClearColor (0.0f, 0.1f, 0.3f, 1.0f); glEnable (GL_CULL_FACE); glEnable (GL_DEPTH_TEST); printf ("GL_RENDERER = %s\n", (const char *) glGetString (GL_RENDERER)); } int main (int argc, char *argv[]) { glutInit (&argc, argv); glutInitWindowPosition ( 0, 0); glutInitWindowSize (200, 200); glutInitDisplayMode (GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH); glutCreateWindow (argv[0]); glutReshapeFunc (Reshape); glutKeyboardFunc (Key); glutDisplayFunc (Redisplay); glutIdleFunc (Idle); Init (); glutMainLoop (); return 0; }