All Questions
Tagged with pbr importance-sampling
6
questions
2
votes
0
answers
129
views
"Charlie" Sheen BRDF's directional albedo integrates to values higher than 1 at low roughnesses. Does this mean it is not energy conserving?
I am implementing the BRDF from the 2017 paper "Production Friendly Microfacet Sheen BRDF". This BRDF is modelled as a coat layer stacked on top of a base specular. In order to do so in an ...
0
votes
0
answers
179
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One-sample model Multiple Importance Sampling with balance heuristic
Recently I feel a bit confused about one-sample model MIS. One sample model MIS can be found here in Veach 1997. 9.2.4 The one-sample model, and this one-sample model is widely used in the opensource ...
0
votes
2
answers
495
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PBR : Understanding importance sampling
I have read this article
On PBR and in it we have NDF function defined as follows
Then I have read this article on random vector generation
Here are what I feel are the important bits.
Now jump to ...
1
vote
1
answer
2k
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Can't understand the Importance sampling GGX
I've read many articles relating to importance sampling of GGX. However, I still feel confused.
The formula of GGX is :
And many article says we should use this formula to sample:
In the formula, ...
3
votes
1
answer
475
views
Importance Sampling in Unreal Engine Formula Derivation (Irradiance term)
I am currently trying to understand IBL in Unreal Engine, and there are so much things that I don't understand about the formula. Unreal approximate the specular term of shading equation by doing ...
1
vote
0
answers
148
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How to make Convolved Diffuse and Specular image in C#
I am trying to take either a HDR panoramic or HDR cubeMap and from that create a Lambert Irradiance environment map and a Cook-Torrence Specular environment map.
I am stuck at the proper ...