Questions tagged [specular]
The specular tag has no usage guidance.
39
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Path tracing the Cook-Torrance BRDF
-- Sorry for the long post, but I prefer to do that way because "Devil is in the details." :)
I am writing a path tracer from the scratch and it is working nicely for perfectly diffuse (Lambertian) ...
user5681
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2
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How to properly combine the diffuse and specular terms?
As far as I understand, in a BRDF the Fresnel term is telling us the probability for a photon to be reflected or refracted when it hits a surface.
The reflected photons will contribute to the ...
- 4,420
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What is the accepted method of converting shininess to roughness, and vice versa?
Most modern renderers use physically-based materials and their models are often parameterized over roughness. Since this wasn't always the case with renderers, conventional assets often don't have a ...
- 2,214
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What is the difference between glossy and specular reflection?
What is the difference between glossy and specular reflection?
What is their relations with BRDF?
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Trying to implement Microfacet BRDF but my result images are wrong
I am trying to implement microfacet BRDF model. I am reading Sebastien Lagarde's slides. I implemented formulas to my code but i think result image is wrong.
Yellow is base color of material. ...
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Should ideal specular multiply light colour with material colour?
Ideal specular reflection is like a perfect mirror. I'm looking at the code to SmallPt and see that one of the spheres has an ideal specular material:
...
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5
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1
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Should not specular reflection on a rough surface be similar to diffuse reflection?
Different BRDFs are usually used to compute diffuse and specular reflection.
Some of the most often used include for example the Lambert BRDF for diffuse reflection and the Cook-Torrance BRDF for ...
- 1,861
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Fresnel and specular colour
I'm trying to implement Cook-Torrance BRDF and had previously bookmarked this question as it looked very well thought out. Going through it, I'm confused about the Fresnel equation. The author has the ...
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Phong and the Rendering Equation: What's with the cosine?
Ignoring emission and shadowing for simplicity, the rendering equation can be stripped down to:
$$L(x, \, \vec \omega) = \int_{\Omega}{f_r(x, \, \vec \omega^\prime, \, \vec \omega) \, (\vec \omega^\...
- 2,293
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1
answer
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Normal vector in Phong Illumination Model should be normalized?
I'm studying Illumination subject these days and I was given a problem which asks to calculate the intensity using phong illumination model. I'm little bit confused whether I should calculate normal ...
4
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How to handle specular highlights with reflection / total internal reflection in a ray tracer?
Let's say that I have a raytracer that is rendering a scene that includes a refractive object.
When a ray hits the refractive object, I know that I can use the fresnel equation (Schlick's ...
- 7,801
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Data fitting SVBRDF with L-M
I am reading two shot svbrdf capture . I want to understand the data fitting.
For example, I have my input image 3000x2000 pixels, and I divide it to create my source tiles of 192x192 pixels. The way ...
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Phong: Real-time rendering of Metal and Plastic Materials
Using a shader that works like Phong, what would be the difference between painted Metal and plastic?
I seem to remember reading in books years ago, that I no longer have access to, the following:
...
- 133
3
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1
answer
835
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How to create specular surface in Mitsuba Renderer
I am a newbie in computer graphics and I am trying to develop a special case of path tracing really slowly! But first: I came up studying the Mitsuba renderer and one of its uses in the so-called GDPT ...
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How to send shadow rays to window light source with glazing
For rendering an indoor scene where light source is skylight coming in through
the window opening, one can consider the window polyline as the light
source, with the sky distribution, in direct ...
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