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copied!<p>Without looking closely at your code, this is some example FBO code that works for sure (animates the Teapot to a texture, draws the texture to the sides of a spinning cube).</p> <pre><code>#include <GL/glew.h> #include <GL/glut.h> #include <cmath> #include <iostream> using namespace std; namespace render { int width, height; float aspect; void init(); void reshape(int width, int height); void display(); int const fbo_width = 512; int const fbo_height = 512; GLuint fb, color, depth; }; void idle(); int main(int argc, char *argv[]) { glutInit(&argc, argv); glutInitDisplayMode( GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH ); glutCreateWindow("FBO test"); glutDisplayFunc(render::display); glutReshapeFunc(render::reshape); glutIdleFunc(idle); glewInit(); render::init(); glutMainLoop(); return 0; } void idle() { glutPostRedisplay(); } void CHECK_FRAMEBUFFER_STATUS() { GLenum status; status = glCheckFramebufferStatus(GL_DRAW_FRAMEBUFFER); switch(status) { case GL_FRAMEBUFFER_COMPLETE: break; case GL_FRAMEBUFFER_UNSUPPORTED: /* choose different formats */ break; default: /* programming error; will fail on all hardware */ throw "Framebuffer Error"; } } namespace render { float const light_dir[]={1,1,1,0}; float const light_color[]={1,0.95,0.9,1}; void init() { glGenFramebuffers(1, &fb); glGenTextures(1, &color); glGenRenderbuffers(1, &depth); glBindFramebuffer(GL_FRAMEBUFFER, fb); glBindTexture(GL_TEXTURE_2D, color); glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, fbo_width, fbo_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, color, 0); glBindRenderbuffer(GL_RENDERBUFFER, depth); glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, fbo_width, fbo_height); glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depth); CHECK_FRAMEBUFFER_STATUS(); } void reshape(int width, int height) { render::width=width; render::height=height; aspect=float(width)/float(height); glutPostRedisplay(); } void prepare() { static float a=0, b=0, c=0; glBindTexture(GL_TEXTURE_2D, 0); glEnable(GL_TEXTURE_2D); glBindFramebuffer(GL_FRAMEBUFFER, fb); glViewport(0,0,fbo_width, fbo_height); glClearColor(1,1,1,0); glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(45, 1, 1, 10); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glEnable(GL_LIGHT0); glEnable(GL_LIGHTING); glEnable(GL_DEPTH_TEST); glDisable(GL_CULL_FACE); glLightfv(GL_LIGHT0, GL_POSITION, light_dir); glLightfv(GL_LIGHT0, GL_DIFFUSE, light_color); glTranslatef(0,0,-5); glRotatef(a, 1, 0, 0); glRotatef(b, 0, 1, 0); glRotatef(c, 0, 0, 1); glutSolidTeapot(0.75); a=fmod(a+0.1, 360.); b=fmod(b+0.5, 360.); c=fmod(c+0.25, 360.); } void final() { static float a=0, b=0, c=0; glBindFramebuffer(GL_FRAMEBUFFER, 0); glViewport(0,0, width, height); glClearColor(1.,1.,1.,0.); glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(45, aspect, 1, 10); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glTranslatef(0,0,-5); glRotatef(b, 0, 1, 0); b=fmod(b+0.5, 360.); glEnable(GL_TEXTURE_2D); glBindTexture(GL_TEXTURE_2D, color); glEnable(GL_DEPTH_TEST); glEnable(GL_CULL_FACE); glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); glDisable(GL_LIGHTING); float cube[][5]= { {-1, -1, -1, 0, 0}, { 1, -1, -1, 1, 0}, { 1, 1, -1, 1, 1}, {-1, 1, -1, 0, 1}, {-1, -1, 1, -1, 0}, { 1, -1, 1, 0, 0}, { 1, 1, 1, 0, 1}, {-1, 1, 1, -1, 1}, }; unsigned int faces[]= { 0, 1, 2, 3, 1, 5, 6, 2, 5, 4, 7, 6, 4, 0, 3, 7, 3, 2, 6, 7, 4, 5, 1, 0 }; glEnableClientState(GL_VERTEX_ARRAY); glEnableClientState(GL_TEXTURE_COORD_ARRAY); glVertexPointer(3, GL_FLOAT, 5*sizeof(float), &cube[0][0]); glTexCoordPointer(2, GL_FLOAT, 5*sizeof(float), &cube[0][3]); glCullFace(GL_BACK); glDrawElements(GL_QUADS, 24, GL_UNSIGNED_INT, faces); glCullFace(GL_FRONT); glDrawElements(GL_QUADS, 24, GL_UNSIGNED_INT, faces); glDisableClientState(GL_VERTEX_ARRAY); glDisableClientState(GL_TEXTURE_COORD_ARRAY); } void display() { prepare(); final(); glutSwapBuffers(); } } </code></pre> <p>Just for reference to have something that works.</p>

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