[PD] per-pixel time based(with memory) effects, is it possible with fragment shaders?

Mathieu Bouchard matju at artengine.ca
Mon Jan 7 07:34:14 CET 2008


On Mon, 7 Jan 2008, Roman Haefeli wrote:

> in gridflow you only need a handful of objects and it is faster than my 
> gem-pix-to-sig-to-pix approach and python, though it is still quite 
> slow. i can now run 320x240 * 20fps in realtime. but more important: 
> with gridflow it's quite simple to do and very flexible.

I just thought of another way of doing slitscanning that runs much faster. 
You need to use a [#store] with "put_at" and write at a different row each 
time while reading back the image in whole rows. e.g. you send a 
(240,2)-sized grid to the left of the store. This avoids any clumsy 
copyings of the buffers. To make it work with columns, do it with rows but 
flip the image along the main diagonal using [#transpose].

I think that I'll try to do it in cellular_1d.pd soon, to replace the 
current junk.

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| Mathieu Bouchard - tél:+1.514.383.3801, Montréal QC Canada


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