All Questions
Tagged with pbr physically-based
12
questions
1
vote
1
answer
66
views
Is the dichromatic model physically based?
lately I have been learning about photometry, and everywhere I look I see a BRDF written according to the "dichromatic model". Roughly speaking: $$\rho= \rho_D+\rho_S \cdot (...)$$
for some $...
- 113
0
votes
1
answer
99
views
PBR pipeline with multiple HDR images?
I believe I already know the answer to this question, but I want to make sure I'm understanding this correctly. Within a physically based rendering pipeline, you calculate your indirect lighting from ...
- 105
0
votes
0
answers
66
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Is casting a shadow ray non-symmetric in pbrt?
According to the description in the book, Scene::IntersectP() "checks for the existence of intersections along the [passed] ray". This operatorion should be ...
- 203
1
vote
1
answer
1k
views
Roughness Value of (Close to) Zero in Physically Based Rendering
In my Direct Light Physically Based Renderer, when I set the roughness too low (ie. 0.0 or close) the specular reflection doesn't show, not even at high resolutions and at perfect angle with the ...
- 163
6
votes
2
answers
4k
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How to calculate attenuation and radiance in PBR? (point and directional lights)
I would like implement physically based rendering, following this tutorial
I was able to find a list of light sources ordered by lumens, but I have no idea how to use it in the calculations.
...
- 278
6
votes
1
answer
135
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Monte Carlo Integration
Let $I$ = the value of integration and $p$ = probability distribution.
The estimator is denoted as $\left\langle I \right >$ and is
$$\left\langle I \right >=\frac{1}{N}\sum_{i=1}^{N}\frac{f(...
- 523
6
votes
1
answer
819
views
The reciprocity of BRDF
Many books describe that a BRDF has the following property (reciprocity):
$$f_r(x, \Theta \to \Psi ) = f_r(x, \Psi \to \Theta)$$
Why is the above equation correct?
I think the above equation ...
- 523
5
votes
0
answers
140
views
What is the potential equation in PBR?
I'am studying PBR and the book introduce the potential equation.
They said the potential equation can describe shooting algorithms better, and
$W(x, \theta)$ describes the fraction of the radiance $L(...
- 523
2
votes
0
answers
448
views
Is there a material table for the Cook Torrance BRDF?
Is there a material table that lists all the specific values to obtain a certain type of material (e.g: copper or asphalt) available?
I found this table in the paper: A Reflectance Model for ...
- 2,511
1
vote
3
answers
358
views
How are Physically Based Rendering Methods Researched?
Recently a question that came to my mind was that How are Physically Based Rendering Techniques researched and developed? Do people just use current equations by physicists or do they create their own?...
- 2,511
5
votes
1
answer
223
views
Error with tube lighting
I have recently been working on area lights for a small open source game engine called Urho3D but have run into an issues when rendering tube lights where the lights look the same as sphere lights ...
- 91
11
votes
3
answers
2k
views
16bit half-float linear HDR images as (diffuse/albedo) textures?
So I been thinking about this for a while and tried to google for an answer but without any success.
If all your textures are 8bit LDR images, like JPEGs, couldn't that potentially cause conflicts ...
