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zerogee
08-06-2010, 10:16 AM
Hello Pavel,

first of all I`d like to underline, it is a HUGE thing and very kind of you that your shader-pack is free and you are always somewhere around to listen for bug reports or questions about p_shaders.

Now I `d like to ask you whether the following list of features are possible to implement in your pack

megaTK:



The ability to create light sets: Separate diffuse pass for arbitrary set of lights. For example: light/lights selected by the user should be in separate passes than other lights. Including IBL as a lightsource.
primary and secondary indirect passes
self shadow on/off like in p_shadow
custom names for specialC1.... passes
occlusion ID (like in mib_amb_occlusion)
A similar BRDF section like in mia_material
built in translucency (I know there is p_scatter wrap, but it would be more convenient to place it on the main shader)
lightshaders

I do not know that exactly what your lightshaders are doing (I am not a mr programmer) except that they are required if someone would like to render in passes. Is there a way to link the native mr lightshaders into a new lightshader which only adds that "extra" thing for passes while maintaing the features of the native light shaders? (I really miss portal light, maya area light, and physical light...)
lens shaders

360 degrees lens shader
Thank you very much in advance...

0G

Puppet|
08-06-2010, 10:51 AM
p_MegaTK
1. It's problem for GUI and control such stuff.
2. What you mean primary and secondary? Two separate passes for indirect? Shader just call mr API function for get indirect color.
3. ...
4. Possible I'll do it in next version.
5. Possible I'll do it too. But now you may use mib_amb_occlusion or any other occlusion shader in "Custom Occlusion" slot. Don't forget set "Samples" in internal occlusion to 0 in this case.
6. p_MegaTK have some BRDF stuff, but not like mia_material. It's "Fresnel" parameter. You can control BRDF curve only with IORs. It's not possible to control BRDF curve with custom value like in mia with "Use Fresnel"=off.
7. Possible I'll do it.
8. My light shaders are based on mr native light shaders (like mib_light_spot, mib_light_spoint and mib_light_infinite) with some useful functionality and some stuff for passes.
physical_light... just forget about it :) it's very simple, old and not usable enough. It's just quadratic attenuation and threshold optimization and nothing more. All these functionality are vailable in TK lights.
Area light... you may use Maya Spot with "Use Area Light" options and p_SpotTK on it.
Portal... I need code my own p_PortalTK...

chuckie7413
08-06-2010, 11:02 AM
Hey puppet.

Again thank you so much for your shaders. They are an invaluable addition to our produciton workflow.

As you are responding to requests, have you ever thought about producing an importance based area light? Similar to the Vray area light. Is this something you would ever consider coding?

Thanks again,

Best,

Rich

jasonhuang1115
08-06-2010, 01:22 PM
As you are responding to requests, have you ever thought about producing an importance based area light? Similar to the Vray area light. Is this something you would ever consider coding?

Rich

Richard you read my mind.....an importance based area light similar to the Vray area light will be AWESOME!!

chafouin
08-06-2010, 01:29 PM
May I ask what makes an importance base area light very interesting? I don't really understand how it works.

cheers.

chuckie7413
08-06-2010, 02:34 PM
At the moment in mental ray, if you were to map a texture lets say 3 stripes of white lines to an area light it would average all the values in the image together to one flat colour.

With an importance sampled based area light you would get lighting illuminating from each of the white lines, defined lighting with independant shadows from each stip of white.

I will do a test and show you.

It means you can map hdr images of say an actual light you have photographed and get correct lighting characteristics and shadows.

chafouin
08-06-2010, 05:58 PM
Thanks for the explanation :)

zerogee
08-16-2010, 06:03 PM
p_MegaTK
1. It's problem for GUI and control such stuff.
2. What you mean primary and secondary? Two separate passes for indirect? Shader just call mr API function for get indirect color.
3. ...
4. Possible I'll do it in next version.
5. Possible I'll do it too. But now you may use mib_amb_occlusion or any other occlusion shader in "Custom Occlusion" slot. Don't forget set "Samples" in internal occlusion to 0 in this case.
6. p_MegaTK have some BRDF stuff, but not like mia_material. It's "Fresnel" parameter. You can control BRDF curve only with IORs. It's not possible to control BRDF curve with custom value like in mia with "Use Fresnel"=off.
7. Possible I'll do it.
8. My light shaders are based on mr native light shaders (like mib_light_spot, mib_light_spoint and mib_light_infinite) with some useful functionality and some stuff for passes.
physical_light... just forget about it :) it's very simple, old and not usable enough. It's just quadratic attenuation and threshold optimization and nothing more. All these functionality are vailable in TK lights.
Area light... you may use Maya Spot with "Use Area Light" options and p_SpotTK on it.
Portal... I need code my own p_PortalTK...

Hi Pavel,

I am sorry for the late reply but we are on a killer deadline...
Thank you for all your - "Possible, I`ll do it" - sentences :)

continuing the previous points... ( I don`t wanna press it too much, just trying to give you examples ensuring that we are on the same page)

1. Per light passes: I thought about a similar system like in luma nexus... link (http://www.luma-pictures.com/nexus/index.htm)
You already have an sd_light_category attribute, to fine control the lights in the scene, for example: for dedicated specular only light per shader. That is why I thought that you are not that far from implementing per light passes...
2. I just thought that it would be nice to control the amount of color bleeding in post. Just like in final gather the primary and the secondary diffuse bounces.
6. OK. I understand... :(
8. After a couple more tests, with spot area versus native area I gotta agree with you...

and thank you again...

kiryha
08-17-2010, 07:31 AM
It would be great to have ability to create layer override for the filename in the p_MegaTK_pass node.

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