/** * Test glGetTexImage() * Brian Paul * 9 June 2009 */ #include <stdio.h> #include <stdlib.h> #include <math.h> #include <GL/glew.h> #include <GL/glut.h> static int Win; static void TestGetTexImage(void) { GLuint iter; GLubyte *data = (GLubyte *) malloc(1024 * 1024 * 4); GLubyte *data2 = (GLubyte *) malloc(1024 * 1024 * 4); glEnable(GL_TEXTURE_2D); printf("glTexImage2D + glGetTexImage:\n"); for (iter = 0; iter < 8; iter++) { GLint p = (iter % 8) + 3; GLint w = (1 << p); GLint h = (1 << p); GLuint i; GLint level = 0; printf(" Testing %d x %d tex image\n", w, h); /* fill data */ for (i = 0; i < w * h * 4; i++) { data[i] = i & 0xff; data2[i] = 0; } glTexImage2D(GL_TEXTURE_2D, level, GL_RGBA, w, h, 0, GL_RGBA, GL_UNSIGNED_BYTE, data); glBegin(GL_POINTS); glVertex2f(0, 0); glEnd(); /* get */ glGetTexImage(GL_TEXTURE_2D, level, GL_RGBA, GL_UNSIGNED_BYTE, data2); /* compare */ for (i = 0; i < w * h * 4; i++) { if (data2[i] != data[i]) { printf("glTexImage + glGetTexImage failure!\n"); printf("Expected value %d, found %d\n", data[i], data2[i]); abort(); } } } printf("Passed\n"); glDisable(GL_TEXTURE_2D); free(data); free(data2); } static GLboolean ColorsEqual(const GLubyte ref[4], const GLubyte act[4]) { if (abs((int) ref[0] - (int) act[0]) > 1 || abs((int) ref[1] - (int) act[1]) > 1 || abs((int) ref[2] - (int) act[2]) > 1 || abs((int) ref[3] - (int) act[3]) > 1) { printf("expected %d %d %d %d\n", ref[0], ref[1], ref[2], ref[3]); printf("found %d %d %d %d\n", act[0], act[1], act[2], act[3]); return GL_FALSE; } return GL_TRUE; } static void TestGetTexImageRTT(void) { GLuint iter; GLuint fb, tex; GLint w = 512; GLint h = 256; GLint level = 0; glGenTextures(1, &tex); glGenFramebuffersEXT(1, &fb); glBindTexture(GL_TEXTURE_2D, tex); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, w, h, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL); glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fb); glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, tex, level); printf("Render to texture + glGetTexImage:\n"); printf(" Testing %d x %d tex image\n", w, h); for (iter = 0; iter < 8; iter++) { GLubyte color[4]; GLubyte *data2 = (GLubyte *) malloc(w * h * 4); GLuint i; /* random clear color */ for (i = 0; i < 4; i++) { color[i] = rand() % 256; } glClearColor(color[0] / 255.0, color[1] / 255.0, color[2] / 255.0, color[3] / 255.0); glClear(GL_COLOR_BUFFER_BIT); /* get */ glGetTexImage(GL_TEXTURE_2D, level, GL_RGBA, GL_UNSIGNED_BYTE, data2); /* compare */ for (i = 0; i < w * h; i += 4) { if (!ColorsEqual(color, data2 + i * 4)) { printf("Render to texture failure!\n"); abort(); } } free(data2); } glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0); glDeleteFramebuffersEXT(1, &fb); glDeleteTextures(1, &tex); printf("Passed\n"); } static void Draw(void) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); TestGetTexImage(); if (glutExtensionSupported("GL_EXT_framebuffer_object") || glutExtensionSupported("GL_ARB_framebuffer_object")) TestGetTexImageRTT(); glutDestroyWindow(Win); exit(0); glutSwapBuffers(); } 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(0.0, 0.0, -15.0); } static void Key(unsigned char key, int x, int y) { (void) x; (void) y; switch (key) { case 27: glutDestroyWindow(Win); exit(0); break; } glutPostRedisplay(); } static void Init(void) { } int main(int argc, char *argv[]) { glutInit(&argc, argv); glutInitWindowPosition(0, 0); glutInitWindowSize(400, 400); glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH); Win = glutCreateWindow(argv[0]); glewInit(); glutReshapeFunc(Reshape); glutKeyboardFunc(Key); glutDisplayFunc(Draw); Init(); glutMainLoop(); return 0; }