multiple pass

[LuCiO]

Hi i've a problem... i want to render some pass in one render time...
I've seen that xsi have the ability to render multiple pass with no extra time and no extra shader... I've seen ctrl buffer also, but is not the same... Now this is the question... is there a way to output spec color refl ecc. with ONE standard maya/MR shader? like xsi??
I'm confused couse the renderer is the same, but xsi do it and maya no why??
the desired pass are
COLOR
DIFF
SPEC
AMBIENT
IRRADIANCE
SADOW
REFLECTION
REFRACTION

tnx...

[mattMR]

Hello,

normaly you can use the shader from Puppet, the p_megaTK shaders that export many passes from one universal shader in one render time. you can also ouput all passes in a single EXR file whose contain all your passes, z and RGBA base render...etc...

go to this link : http://puppet.cgtalk.ru/download/shaders_p_e.shtml

Best regards

Matt

[haggi]

The reason why you cant do it from maya is that the shader is responsible for the generation of these passes. Maya shaders dont create passes. XSI shaders do create these passes in the shader.

And the best solution is to use the shaders Matt mentioned.

[LuCiO]

Tnx for reply... but i've used the puppet shader, it's no so easy... i've some trouble with filter... the documentations says that u cannot use filter like mitchell... and this is not good for my works..another stuff is that u must use only puppet lights, there aren't any parameters for symple traslucency like standard blinn and. so on....However i was think to write a shader like the standard maya blinn that output this pass...

Now my question is...
A simple phenomena with some buffer store (ctrl studio) and some standard shader can do what i need?
sorry for my very poor english

[mattMR]

yes,

you can also use a phenomenom with ctrl_buffer, it'll work. the pavel's shaders are very usefull and you don't need to connect shader to an output shader...etc...etc... but the CTRL_buffer shader can do the same job. the difference beetween the 2 shaders is, one is compil to be a universal shader (all function are in) and the other is a shader that can be modulate... for myself, mitchell filter do a high contrast but do some artefact, in some ways, with or without P_mega_tk shaders (on fur or shave, mitchell makes black spots area due to the algorythm use). I always use triangle or gauss.

best regards.

Matt

[Puppet]

For traslucency effect you may use maya shaders for example Maya Lambert, disable diffuse and enable only traslucency in it and connect to p_MegaTK.ambient.

mitchell and lanczos filters not recommneded not for p_MegaTK passes only(for p_MegaTK passes mostly) and for any rendering to float point format if you plane to compositing.

[LuCiO]

tnx to all for replies and help... now i've my phen. and i'm able to output these pass (color,diff,refraction,reflection,spec) exactli like in xsi...Now i'm very happy for my work (because is the firt time with phenomena ) but i want some other pass. one of these is irradiance...
I'm try very hard these day to output a pass with only fg but i can't...I have tried to use ctrl_irradiance and some raytype for exclude fg for the all the other shader (diff col.spec ecc..) and then put only the irradiance in a separate FrameBuffer... The problem is: i render with the fg and the result is also in the other frameBuffer like diff.. and i wasn't able to separate it in only one.... someone can help me??
P.S. for almost all shader i use custom MR shader no standard maya shader.. so i don't have irradiance parameter to tweak...

TNX

[Puppet]

but i've used the puppet shader, it's no so easy... i've some trouble with filter... the documentations says that u cannot use filter like mitchell...

You may use any filters, but I recommend triangle. It's not my shader only problem. If you'll use ctrl_buffer or any other shaders that use user frame buffers you'll have same problem.
It's mental ray core problem with filtering user frame buffers including last version at current time (3.5.6.7).

I'm try very hard these day to output a pass with only fg but i can't...I have tried to use ctrl_irradiance and some raytype for exclude fg for the all the other shader (diff col.spec ecc..) and then put only the irradiance in a separate FrameBuffer...

Do you really think that is more simple than use one p_MegaTK shader?

The problem is: i render with the fg and the result is also in the other frameBuffer like diff.. and i wasn't able to separate it in only one....

Sorry, what you try to do, can you explain more detail?

[LuCiO]

Do you really think that is more simple than use one p_MegaTK shader?

ahahah yeah i know that is more simple use your shader, but the main goal of this "work" is learn much more in detail MR... However your shader look a little bit different to what i want... for ex. in your example scene N.2 you have a ball with a checker as opacity....In checker's black zone the ball disappear completly... instead to become trasparent... it means that i can't have reflection in that zone... if u map a checker in trasparency channel in standar maya blinn and put reflectivity to the max the refl. appear also in checker's black parts... how can do this with your shader? maybe (for sure ) i'm not able but is possible.... however the main goal of this project is learn...

You may use any filters, but I recommend triangle. It's not my shader only problem. If you'll use ctrl_buffer or any other shaders that use user frame buffers you'll have same problem.
It's mental ray core problem with filtering user frame buffers including last version at current time (3.5.6.7).

Can you show me these artifact please...with some exmple img?? so i'll understand which kind of artifact occurs

Sorry, what you try to do, can you explain more detail?

i want to have the irradiance pass as a separate FrameBuffer...like your indirect ill.pass... or the standard maya global illumination pass in render layers... i've tried also your p_irradiance but i've not understand how does it works i've used (for my phen) the framebuffer Write and frame buffer output (http://www.impresszio.hu/szabolcs) with some shader attach to frame bufferwrite and the combination (mix8layer) attach to the framebuffer write render slot....
so i've in viewport the right render and all pass in FB...and it's right...
now the prob.
If i render with FG the result is show also in diffuse FB... and i don't want that... i want to have a single pass with indirect illumination to "add" later in compositing and all the other pass without FG.... how can i do??

TNX A LOT

[mattMR]

Hummm...

I use this shader every day and I just to check the indirect pass to have my indirect pass... for reflection and refraction controled by a checker... maya's opacity it's not the same way as p_megatk shader... opacity in p_megatk is the transparent shader... for refraction and reflection on the shader... use your map in refraction and reflection shader... maya material and mr shader are totaly a different approach. for artefact... when you composite your image in float channel, some black, green or red dot appear randomly.

PS : Puppet, your shaders work perfectly under maya 8.5

Matt