Questions tagged [specular]
The specular tag has no usage guidance.
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Blinn-Phong specular light bleeding on triangles facing-away from light: what is the canonical solution?
In our implementation of the empirical Blinn-Phong shading model, we are facing a problem with light-bleeding of the specular component.
The model defines the half-vector $\vec{h} = \frac{\vec{v} + \...
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"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 ...
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Confusion over Microfacet-based BRDFs and Normal Distribution Functions
Through reading various sources online, I've become a bit confused. I'll briefly outline what I think I do understand:
My understanding is that microfacet-based BRDFs assume there is always a perfect ...
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Unable to compute fresnel reflections properly
I am implementing fresnel reflections for materials in my renderer.
According to this source, here the look I should obtain when rendering a sphere over a grey background:
I have two implementations. ...
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Does fresnel reflection make sense for metals?
I am implementing fresnel reflections for materials in my renderer.
Does it make sense for metals?
Here my implementation:
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What does GGX stand for?
Many render engines implement the microfacet model for rendering surfaces that are rough, metallic, and/or transparent, a concept first published in "A Reflectance Model for Computer Graphics&...
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How can I transform the circular blinn-phong specular into a square shaped highlight?
I am creating a custom shading model in Unreal Engine and I would like to create a square shaped specular highlight, without changing the shape of the light itself.
I tried following the approach ...
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Calculation of reflection vector in Phong specular lighting
I wrote the following phong reflection model for ray tracing in Rust, but I am not sure about the calculation of a reflection vector for the specular reflection.
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Temporal reprojection of specular reflection - finding previous frame color
In specular reflection result depends on view vector from camera to point. Because of that, when doing temporal reprojection and reprojecting position of current fragment while camera is translating, ...
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Specular reflection with different viewing direction where reflection direction and viewing direction coincide
Suppose $P_1$ and $P_2$ two different points on surface. And let
$l$: be the light source direction,
$n$: normal vector
$r$: specular reflection direction
$v$: viewing direction .
In case 1 (at $P_1$...
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PBR : Understanding the right part of Split sum integration of specular IBL
This is the website I am learning from.
In the specular part of IBL this is the split sum approximation
Now the left part of the equation I have asked in This post and I have understood everything ...
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Adding specular reflections to a ripple simulation
I am following the algorithm shown in this code here. Essentially there is a simple simulation of heights and then the difference in heights on the x and y axis respectively (sampling adjacent points) ...
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total internal reflection implementation in pbrt-v3
I've been implementing a path tracer, referring pbrt-v3. However, I'm a bit confused about its implementation. Code is here.
It seems when we sample to do transmission, it tests if it meets a total ...
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Cook-Torrance Specular BRDF Artifact [duplicate]
I am currently experiencing a very obvious artifact that occurs when looking at objects on very grazing angles
Here is a picture of the artifact:
I noticed that the issue was coming from my ...
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Normal Artifacts On Grazing Angles
I am currently experiencing a very obvious artifact that occurs when looking at objects on very grazing angles
Here is a picture of the artifact:
I noticed that the issue was coming from my ...
- 51