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View Full Version : Problem : GL_FEEDBACK mistake.



gaby
11-16-2000, 09:33 AM
Hi,

I try to get the screen coords of a point with a feedback rendering, but it doesn't work.

glMatrixMode(GL_MODELVIEW);
GLfloat buffer[4];
glLoadIdentity();
glFeedbackBuffer(4, GL_3D, buffer);
glRenderMode(GL_FEEDBACK);
glBegin( GL_POINTS );
glVertex3f( 1, 1, -1);
glEnd ();
CheckError (glGetError());

Check error is stopped by a GL_INVALID_OPERATION code (????).
Should anyone help me, please, taking care i need to get the depth (0->1.0) to read the w-buffer after, for the determination of the visibility of that point.

Please, help me !

Gabriel RABHI / Z-OXYDE / France