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gl shared context nightmare

March 19, 2009 | 7:12 pm

Dear list,

I’ve made this rutt etra patch that I want to key ontop of a database visualization that I’ve made. The data visualization takes place in an mxj and is drawn to a different gl render context which is captured to a texture so I can post process it and then luma key it with slabs. However instead of the data visualization appearing keyed over the top I get a squashed copy of the texture I’m colouring the rutt etra with.

When I connect a jit.matrix and jit.pwindow to check what’s in the texture I’m capturing the data visualization to I can see my visualization fine. The output of this texture is fed into a blur slab and when I check the output of this I see the squashed texture from somewhere else in the patch.

I’ve successfuly used a shared context to share a texture in a stripped down version of the patch and processed the output texture but it seems to go haywire when I try and use the technique with so many other textures.

Has anyone else experience a problem like this ?

March 19, 2009 | 7:31 pm

here is a cut down version of the patch, i’ve included the classes and source for the java mxj, just drop them in Cylcing ’74/java/classes . When you open it it’ll ask you for a video to play, then hit space bar to get it rendering and look in the subpatch called render-data-overlay, I’ve left the jit.pwindows doing the texture readback in there so you can see what I’m talking about.

Hope someone has an idea because right now I’m stumped.

March 19, 2009 | 11:35 pm

The only work around I’ve been able to find is to dump the texture to a matrix and then back out into another texture, this seems stupid. What’s the clever way to do this?

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