> Um he stated the projection matrix is undocumented because its identity, ie, 
> it is not ever messed with, and even if it was, you could glGet it.

Not quite -- I didn't say it was identity (it is in fact _not_ -- verifying 
this is a glGet away, as you've noted), just that it's synthesized once, and 
then not touched after it's configured (it's used to position the camera on the 
Z axis, for example, which an identity matrix cannot possibly do).  It's 
undocumented because QC has never documented its matrices, and doesn't have any 
plans to that I'm aware of (because there's no reason to do so).

Identity matrix has a special meaning, and QC's Projection matrix does not 
satisfy that meaning at all.

With all this chatter I'm surprised someone hasn't done:

GLfloat mat[16];
glGetFloatv(GL_PROJECTION_MATRIX, mat);
NSLog(... the matrix stuff ...);
glGetFloatv(GL_MODELVIEW_MATRIX, mat);
NSLog(... the matrix stuff ...);

It's a lot of code, I know, but it's way more exciting than guessing and/or 
arguing :)

To answer George's question:  correct, there's no way to do this generally with 
built-in patches.  If you make some assumptions (i.e. that the projection 
matrix won't change, and that the modelview matrix won't change), you can do it 
by manually finding out the matrices "offline", and then pretending they're 
constant, but it'll break down in trackballs et. al. where the constant-matrix 
requirement no longer holds.  

--
Christopher Wright
[email protected]



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