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ckas
02-04-2005, 06:10 AM
anybody any idea how to use user framebuffer in maya 6.5 properly??? (parallel depthpass, occlusionpass, etc)
thanks

Puppet|
02-04-2005, 08:56 AM
For example Maya use user buffer 0 for glow.

You may write shader that will write some info to user buffers.
Or you may use this one:
http://www.puppet.cgtalk.ru/download/buffer_writer_e.shtml
http://www.puppet.cgtalk.ru/download/shaders_p_e.shtml
Also you should write output shader for write image from user buffers.

But better forgot about GUI user buffer and use custom texts + mental ray stand alone. It's more powerfull.

Why Alias limit user buffer number to 8 (mental ray 3.4 support unlimited number of frame buffers)?
It's no enough for real production!

Jackdeth
02-04-2005, 04:13 PM
For example Maya use user buffer 0 for glow.

You may write shader that will write some info to user buffers.
Or you may use this one:
http://www.puppet.cgtalk.ru/download/buffer_writer_e.shtml
http://www.puppet.cgtalk.ru/download/shaders_p_e.shtml
Also you should write output shader for write image from user buffers.

But better forgot about GUI user buffer and use custom texts + mental ray stand alone. It's more powerfull.

Why Alias limit user buffer number to 8 (mental ray 3.4 support unlimited number of frame buffers)?
It's no enough for real production!

Very cool. Do you have any Linux versions? I can help you if you don't.:thumbsup:

Bonedaddy
02-04-2005, 06:43 PM
For example Maya use user buffer 0 for glow.

You may write shader that will write some info to user buffers.
Or you may use this one:
http://www.puppet.cgtalk.ru/download/buffer_writer_e.shtml
http://www.puppet.cgtalk.ru/download/shaders_p_e.shtml
Also you should write output shader for write image from user buffers.

But better forgot about GUI user buffer and use custom texts + mental ray stand alone. It's more powerfull.

Why Alias limit user buffer number to 8 (mental ray 3.4 support unlimited number of frame buffers)?
It's no enough for real production!

That's pretty cool. I've been wondering whether mray had something equivalent to prman's extra output channels. Does
it cause much of a hit on render times?

Ze PilOt
02-04-2005, 06:59 PM
I'm very interesting in the way to output these buffers to files... Seems that the method differs a lot from 3.3 and 3.4 (3.4 write directly the file during the render process, but delete it at the end, 3.3 keeps it in memory), and a lot of functions are obseletes in 3.4 about framebuffers.. So how can I do it ? :)

francescaluce
02-05-2005, 01:16 AM
if you have a shader that write to a framebuffer.. you don't need anything else.. apart a mentalray standalone.
with maya65 you'll need just to enable the framebuffers(rg->framebuffer->userframebuffer), select the camera then go to window->rendereditors->mentalray->customtexteditor and add(preface) one line for each framebuffer to output a file to disk(output "fb1" "ct" "c:/outfb1.ct")[or use a multichannels openexr].. customnodes are now directly exported.. so export and go straight to render. :p


ciao
francesca

ckas
02-05-2005, 04:19 AM
thanks
but could you explain your line with a sentence ( ct stands for colour?)
and for a parellel occlusion output, ......????


something like a preset mel would be nice, with a little interface to select possible passes, and then adds these codes to the cameras....

Ze PilOt
02-05-2005, 09:55 AM
if you have a shader that write to a framebuffer.. you don't need anything else.. apart a mentalray standalone.
with maya65 you'll need just to enable the framebuffers(rg->framebuffer->userframebuffer), select the camera then go to window->rendereditors->mentalray->customtexteditor and add(preface) one line for each framebuffer to output a file to disk(output "fb1" "ct" "c:/outfb1.ct")[or use a multichannels openexr].. customnodes are now directly exported.. so export and go straight to render. :p


ciao
francesca

My question was of course for mayatomr, not the standalone :)

Puppet|
02-05-2005, 01:07 PM
Sorry, I forgot that my p_buffer_writer shader only for mental ray 3.3 and early because mental ray 3.4 have different method of work with buffers.

Soon I'll rewrite p_buffer_writer for mental ray 3.4.

it cause much of a hit on render times?
Render time is same if you'll use any layer shaders for example mib_color_mix.
But main problem with custom buffers is that samples take from main(render) buffer, that are user buffers don't have independent sampling. In result you may get oversampling where it's not need and low sampling where need more samples.

For output custom buffers you need create custom text on camera (that francescaluce said) and use mental ray stand alone or if you don't have mray stand alone you'll need write output shader that will save to file custom buffers.

I don't have linux version of my shaders because I'm not familiar with linux and I was wondering if someone compile or help me to compile linux versions of my shaders. I suppose it's very simple but I have no time to learn how to do it in linux.

caretz
09-23-2005, 10:32 AM
francesca or puppet do U think U guys can post an example of a simple output shader using a multichannel Exr ?
tnx a lot

-a

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