Creating a separate pass for color bleedings

[machasone]

Hi all,

I would like to know how I could create a separate pass for color bleeding using mia material x pass in maya 2011.
If you have done this before or know hints, please help me out><
I got stuck at this problem whole day...

Thank you very much for your help in advance.

Machasonecomp_GI_room_2.png

[bart]

Color bleeding typically comes from indirect light hitting a diffuse surface, in other words light from objects that hit the point you are looking at. So there is an indirect output available from mia_material_x. That represents indirect diffuse reflection.

Do you need help using the Custom Color framebuffer passes in Maya? Or are you using only the Maya builtin passes?

[machasone]

Mr bart,

I really appreciate for your help.
Yes, I could extract only color bleed info by using indirect output!!
I tried the maya builtin pass, however, it seems the pass can't output color bleeding from every single light separately. For exapmle I wanted to get color bleeding info from an IBL and a spot light individually, but it mixed color bleeding from both lights together for some reason although I created different associated passes and contribution maps.

I am not so familiar with the custom color framebuffer passes that you mentioned.
I will search it by myself, but could you please teach me in what situation it is useful?


Sincerely,

Machasone


Color bleeding typically comes from indirect light hitting a diffuse surface, in other words light from objects that hit the point you are looking at. So there is an indirect output available from mia_material_x. That represents indirect diffuse reflection.

Do you need help using the Custom Color framebuffer passes in Maya? Or are you using only the Maya builtin passes?

[bart]

Since indirect techniques often include pre-processed approximation techniques, perhaps the best way to separate lights in your case is to use Render Layers. Separate the light or light groups into each Render Layer. Then each render layer will only consider those lights in its indirect lighting phase.

For example, if we are using final gathering, at each final gather point, FG rays are shot out into the scene and then material shaders are called there at each FG ray intersection point. Then, as these material shaders examine the light hitting them, we would have to track that separately for each light or group of lights that you wanted to put together.

A brute force GI technique could possibly make that easier, and indeed future techniques coming may make that easier to implement what the artist arbitrarily specifies.

[machasone]

Mr Bart,

I am very sorry for my late reply. I have not noticed that you already replied my topic.
The problem has been fixed by your help.
Thank you very much!

Sincerely,

Machasone