Wanted delay for gl slabs

Jan 26, 2010 at 5:54pm

Wanted delay for gl slabs

Hello

I have this patch below and I would like to add a delay on the compositing of the second branch of slab which is a duplicate of the incomming signal.
With matrix I used to do it with tap.jit.delay but obviously it can’t work with gl process.

Somebody has an idea ?

– Pasted Max Patch, click to expand. –
#48034
Jan 26, 2010 at 7:41pm

Use a texture buffer if you want to buffer textures. You can do this with javascript. Search the forum, there are a few posts on this. Be aware this uses a lot of VRam, and you may end up going over your max Vram capability. On OS X, if you go over max VRam usage you swap to main memory, and this gets very very slow very fast.

Depending on the size of your textures and your pipeline, you may be able to do an async read back to a matrix, delay it like normal, and then re-upload it to a texture.

#172725
Jan 26, 2010 at 8:32pm

This article discusses the implementation of a texture-based delay buffer: LINK

Keep in mind, as Vade points out, you may run into trouble with VRAM overflow if you are doing a lot of other slab processing.

#172726
Jan 26, 2010 at 11:13pm

So sorry to take time for a question that was already answered through a tutorial :-S

Much thanks, it does exactly what I was looking for even though I don’t understand really the vps.texlut and vps.texset for now.

Thanks also Vade for the warning !
I’m doing a lot of slab processing on particles but it seems ok – my processing is previous to the “frame delay” (don’t know if changes something).

#172727

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