Simon Bennett (simonb++at++wormald.com.au)
Tue, 24 Sep 1996 19:19:59 +1010 (EST)
> Thanks to everyone who's been trying to help me out. Almost everyone
> has recommended spline fog. Unfortunately, when I tried spline fog
> in Vega, it didn't work properly. In addition, we have an Earth/Sky
> environment with clouds, which I am required to not obscure.
> Finally, I am restricted to working in IrisGL, not OpenGL.
>
> Anyone know how to read the depth buffer in IrisGL? It still looks
> to me like post-processing the frame to blend the sky color into
> distant object pixels is still my best bet.
> Onyx/IR2 machine.
IR2? iR? or RE^2?
Regardless...
You *can* read the non-multisampled depth buffer in IRIS GL on RE^2
---
do something like:
readsource(SRC_ZBUFFER);
lrectread(x1, y1, x2, y2, parray);
you *can't* however read the multisampled z-buffer on an RE^2.
You can sort-of read the multisampled z-buffer on an iR. I think
glReadPixels() will return the sample closest to the centre of the pixel
(but not individual sub-sample values). Don't know whether this will work
in for lrectread() thou... I'd doubt it. (I wouldn't use IRIS GL on an iR
either thou!)
Hope this helps...
+----------------------------------------------------------------------------+
Simon Bennett simonb++at++wormald.com.au
Wormald Technology Advanced Systems Engineering Ph: +61 2 9981 0669
"Good judgement is the result of experience.
Experience is the result of poor judgement"
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