creed_nmd
03-18-2004, 09:35 PM
I've been playing around with radiosity and HRDI in Cinema 4D, placing the HRDI in a sky object.
I've been getting out some nice renders, with soft shadows and color-bleed, etc., that have nice 'ambient' lighting from the HDRI.
My question is what to do about speculars?
If I add some reflective values to my materials I get nice speculars from the light parts of the HRDI, but--as is obvious--I also get reflections of the other objects.
Since I've always understood specular hilites in CG packages to be 'fakes', to get over the fact the the lighting isn't 100% physically correct, I'm confused how they work in conjunction with HRDI and radiosity. Do you simply remove the specular values from your materials, and rely on other settings to generate them? If so, how? Or are they still needed?
On the whole issue of other 'standard' lights with HRDI; if the chrome-ball HRDI map 'is your environment' and encodes your lighting values, do you need other lights to light the scene. If so, how?
What I'm having difficulty seeing is the whole lighting picture.
If I use radiosity with a HRDI, is that all I use? Or do I need other lights for shadows/speculars, placing them so they match the 'lights' encoded into the HRDI?
If radiosity use the HRDI to light the scene, and the HRDI has the light info in it, isn't adding extra lights going to blow out the scene by adding lights that were't there, effectively 'doubling' up the lighting?
How about using HRDI in environment maps, without radiosity but using ambient occlusion to generate a psuedo-radiosity look. Do I still need lights in that instance?
Does anyone have a simple explanation of a recipe for what you need for each approach?
TIA
-- Andy W
I've been getting out some nice renders, with soft shadows and color-bleed, etc., that have nice 'ambient' lighting from the HDRI.
My question is what to do about speculars?
If I add some reflective values to my materials I get nice speculars from the light parts of the HRDI, but--as is obvious--I also get reflections of the other objects.
Since I've always understood specular hilites in CG packages to be 'fakes', to get over the fact the the lighting isn't 100% physically correct, I'm confused how they work in conjunction with HRDI and radiosity. Do you simply remove the specular values from your materials, and rely on other settings to generate them? If so, how? Or are they still needed?
On the whole issue of other 'standard' lights with HRDI; if the chrome-ball HRDI map 'is your environment' and encodes your lighting values, do you need other lights to light the scene. If so, how?
What I'm having difficulty seeing is the whole lighting picture.
If I use radiosity with a HRDI, is that all I use? Or do I need other lights for shadows/speculars, placing them so they match the 'lights' encoded into the HRDI?
If radiosity use the HRDI to light the scene, and the HRDI has the light info in it, isn't adding extra lights going to blow out the scene by adding lights that were't there, effectively 'doubling' up the lighting?
How about using HRDI in environment maps, without radiosity but using ambient occlusion to generate a psuedo-radiosity look. Do I still need lights in that instance?
Does anyone have a simple explanation of a recipe for what you need for each approach?
TIA
-- Andy W