Questions tagged [lighting]
The lighting tag has no usage guidance.
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Injecting Virtual point lights into 3D Grid
I am currently trying to implement light propagation volumes in DirectX 11 and I have already done the RSM part which contains position, normal, depth and flux map generation. But for Injecting ...
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How is spectral rendering handled?
Is all spectral rendering handled as simulation? Are there technique more tailored to 'consumer' rendering, such as for real-time or even just 'realistic looking without solving full physical ...
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What is the basis of rendering light caustics?
I am not looking for textbooks and related how-tos, though I'm sure they can color the answer.
I'd like to understand how we handle the rendering of caustic effects — and particularly time-saving ...
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Does light particle loses energy when it hits something?
I have some material which I want to represent as a collection of spheres (atoms) and a particle of light (photon). I'm firing this particle and checking for the collision against atoms. What should ...
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Does PBR incur a performance penalty by design?
I am wondering if the various PBR models used in modern game engines for real time are heavier in terms of computation, that more classic approaches to rendering.
Worded differently, is PBR just a ...
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How to Calculate Surface Normals for Generated Geometry
I have a class that generates a 3D shape based on inputs from the calling code. The inputs are things like length, depth, arc, etc. My code generates the geometry perfectly, however I am running into ...
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How can I get a spherical visibility mask map for a point on a concave surface?
I encountered this problem doing my project. Suppose there is a 3D mesh model, e.g. a human face, I need the 3D visibility map at each of the vertices of this model. By the "3D visibility map", I mean ...
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Legendre Polynomial equation in Spherical Harmonics
I recently started to read about spherical harmonics. I have a question about this spherical harmonics basis function equation which is mentioned in this StupidSH article:
What are those lm() and Re()...
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How is screen space ambient occlusion implemented?
I do not understand the explanation from wikipedia.
For every pixel on the screen, the pixel shader samples the depth values around the current pixel and tries to compute the amount of occlusion ...
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What is ambient lighting?
Wikipedia says:
An ambient light source represents a fixed-intensity and fixed-color light source that affects all objects in the scene equally.
By saying "affects all objects equally" they mean ...
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What is "Object Space Lighting"?
Looking at Star Swarm, a demo for the Nitrous engine, I found this little line:
"Nitrous uses Object Space Lighting, the same techniques used in film, including real-time film-quality motion blur."
I ...
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Multiple Lights Shading - One Pass vs Multiple Passes
I was looking into ways to implement multiple lights shading and I've noticed Unity uses multiple passes to achieve it. It performs a base pass to apply the brightest directional pixel light + 4 ...
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How to build a decent lens/camera objective model for path tracing?
I have written a small path-tracer after learning and experimenting on smallpt.
The only thing that I did not write (and understood) myself is how the initial rays are computed and fired from the ...
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How is a light probe different than an environmental cube map?
Looking at a light probe texture, it looks like a blurry environment map.
What's the difference between the two, how is a light probe made, and what is the benefit of it being blurry?
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How do shaped lights work?
I know how to program directional lights, point lights and spot lights. Sometimes though, people have lights that are shaped - like bars, or even a torus.
How does that work from either a ray based ...
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Efficient rendering with many light sources
To render a scene with a single light source using phong shading, one can calculate the final color of each fragment passed into the fragment shader based on the ambient/diffuse/specular components of ...