Questions tagged [theory]
The theory tag has no usage guidance.
9
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Term confusion about volume scattering
We have two different terms, for example, let's talk about scattering only.
Scattering coefficient
Scattering cross-section
These two terms are supposed to have different physical meaning. I read it ...
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Applying Monte-Carlo methods in path tracing
I've noticed that I consistently get worse results in path-tracing when I try to do monte-carlo correctly compared to when I don't, and I think this might be because of a fundamental misunderstanding.
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FLOP - exact definition
I am interested in how much a GPU can actually calculate. When learning about rendering, it seems like a good idea as well.
My Question:
WHAT EXACTLY is a Floating Point Operation?
I know what a ...
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coverage vs transparency
2D application users seem to be using transparency as a proxy for coverage more often than not. However they are not the same, although nearly everybody makes the assumption that they are.
Given that ...
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Difference betwen Rendering Equation, Lighting model, Ray Tracing, Global Illumination and Shadows?
What is the difference between all these techniques? I know what a lightning model does, eg Phong, Flat, Gouraud. As far as I know both Ray Tracing and Global Illumination are just lighting models ...
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Rendering Fluid Simulations?
I've read about Lagrangian and Eulerian fluid simulations and here's what I take from their methods:
Lagrangian - Simulating fluid particles by calculating displacement for each particle
Eulerian - ...
4
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Pixel density / color channel depth ratio for dithered gradients
Dithering increases percieved color depth by adding a "noise" to an image on transform from high color depth (e.g. 32-bit floating point) to lower color depth (e.g. 8-bit integer). A prerequisite is ...
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Problem with definition of BSDF and radiance
When I was reading theory behind physical based rendering I noticed that definition of BSDF and radiance has some problems. For example BSDF of purely specular surfaces is zero almost everywhere and ...
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Why integrate over a hemisphere (and not a sphere) to solve the rendering equation?
In most text books that I have seen, this is how the rendering equation is written:
$$L_0( \omega_0)= L_e(\omega_0)+\int_{\Omega}{f(\omega_i, \omega_0)L_i(\omega_i)\,\mathrm{d}\omega_i}$$
Where $\...