Questions tagged [raytracing]
Questions specific to raytracing (as opposed to scanline rendering), the 3D graphics technique of intersecting rays from the camera with objects in the scene.
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Explicit Light Sampling: Where does $n \cdot l$ come from?
In these lecture notes: http://www.cs.utoronto.ca/~strider/docs/D18_DistributionRayTracing.pdf on page number 140 (as labelled on the PDF), it says that if we perform explicit light sampling, the ...
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Ideas on how to do ray-tracing for a volume of voxels
I work on medical imaging and would like to use Vulkan ray-tracing to perform the following:
I currently have a volume of voxels (around 500 each dimension) and I want to trace rays from the camera ...
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One-sample multiple importance sampling, with environment and brdf
I am writing a pathtracer, and I want to somehow incorporate importance sampling of the environment map. The obvious way to do this seems to use MIS to either importance sample from my material bsdf ...
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How to ensure energy conservation of a coat layer on top of an arbitrary BSDF?
Recent approximate techniques for energy conservation of conductors / dielectrics rely on the precomputation of the directional albedo for the conductor / dielectric BSDF. [Conty & Kulla 2017], [...
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Ray tracing artifacts along facet edges
I have a CPU-ray tracer and have been struggling to deal with artifacts along facet edges near the terminator (I believe this is a fairly common issue). These were the artifacts I was getting ...
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Issue regarding shadow acne (Ray Tracing)
Hey guys i was trying to render this scene with shadows. The spheres do not have any acne...but the floor and the walls seem to still have the shadow acne problem...
This is the code i have for ...
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Do we have to adapt what we know from physics to forwards vs. backwards ray-tracing?
This is a more theoretical question. I've been following a ray tracing tutorial and I'm a little confused about how some of the properties of these surfaces are rendered. There's a basic diffuse ...
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Question on Adaptive offsetting along geometric normal
I've been attempting to implement an adaptive ray-offset to prevent self intersection when computing bounce rays. This article outlines such an algorithm (specifically in section 6.2.2.4 on page 8).
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Is the Mascot on Github Copilot Enterprise's website "ray-traced"?
This may be a dumb question because I'm a complete novice to graphics programming.
I was on the website of Github Copilot today and I noticed that there's a floating head that follows your mouse ...
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When to apply backface culling, depending on the ray and material type?
I am currently implementing a ray tracer, which supports reflection and refraction.
I have the following types of rays:
camera rays
shadow rays
reflection rays
refraction rays
I have the following ...
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Overweighting certain lights with ray tracing
I'm just getting started with ray tracing with DXR and I'm building some simple lighting with it. I've run into a slight issue; namely, that my game is set in space. Therefore the vast majority of all ...
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How is this transmittance derived?
In PBRT 4ed
https://www.pbr-book.org/4ed/Volume_Scattering/Transmittance#eq:volume-attenuation-differential
How is this transmittance equation transformed from 11.9 to 11.10?
\begin{equation}
\int_0^d ...
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How to have caustics at all in a path tracer with next event estimation?
When doing next event estimation, you trace a shadow ray to a light source to test visibility. What if there's a glass/transmissive object in the way? The light will be occluded and we won't get any ...
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Multiple Importance Sampling BSDF + Light - weights confusion with the number of emissive triangles
I'm trying to implement multiple importance sampling for direct lighting estimation but I'm having a hard time understanding why adding the number of triangles to the PDF of my light sample yields ...
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How is Shader Execution Reordering implemented under the hood?
I am writing a software path tracer from scratch in CUDA (for learning purposes, without resorting to any higher-level graphics API like OptiX), and it is well-known that path tracing can have ...
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