Questions tagged [supersampling]
11 questions
25
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Anti-aliasing / Filtering in Ray Tracing
In ray tracing / path tracing, one of the simplest way to anti-alias the image is to supersample the pixel values and average the results. IE. instead of shooting every sample through the center of the pixel, you offset the samples by some…
RichieSams
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What is the fundamental reasoning for anti aliasing using multiple random samples within a pixel?
In graphics, it's common to take multiple samples within the bounds of a pixel and combine them together (most commonly just doing an average) for a final sample pixel color. This has the effect of anti aliasing an image.
On one hand this makes…
Alan Wolfe
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Math for adaptive supersampling for raytracing
How do I determine how many (jittered) rays to trace for a given pixel, as a function of the statistics of a small initial set of test rays? Also, what size should the initial set be? (it's currently 20, based on eyeball tests)
Currently I'm…
Octa9on
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Sample color calculation in rotated grid supersampling
I'm rendering a scene using scanline method. In order to get rid of aliasing we need to render a scene with higher resolution (2x, for example). I'm trying to figure out how to calculate the color of a sample when it is not taken from the center of…
Paviel Kraskoŭski
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Do animation studios like Pixar, Dreamworks, and Disney use super-sampling?
Does any of their rendering techniques involve rendering an area at a higher resolution just to scale it down in order to mitigate artifacts? I know they use ray methods rather than rasterization however ray methods still have artifacts even when…
J.Doe
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Multiple samples per pixel and texture blurring
As far as I know path tracers (or super-sampling antialiasing) typically calculate the final color of a single pixel by averaging the result of all samples taken inside that pixel. This gives a nice anti-aliasing effect on the edges, however has the…
yggdrasil
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Anisotropic filtering and multisample anti-aliasing
Anisotropic filtering and multisample anti-aliasing both imply supersampling.
In EWA and (derived) Feline AF algorithms a non-uniform weighted average is used. But in case of MSAA not. Why this is the case? Isn't it better to use weighted average in…
Tomilov Anatoliy
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Nearest depth upsampling
Nvidia in this article presented a way to upsample low res buffer to full res buffer called Nearest Depth Upsampling.
This works by comparing four depth values from downsampled low res depth buffer with current value of full res depth buffer and…
narthex
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Ray tracing Supersampling patterns : pre-computing them?
This wikipedia page explains the principle of patterning in Supersampling.
However, I have a question: should the pattern be constant for every pixel?
Of course, the pattern will be constant for a "grid algorithm" but for the "random algorithm",…
user18228
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MSAA performance with forward shading
I have done some tests in OpenGL with multisampling, by specifying a multisample buffer as the default framebuffer. I used forward shading for rendering. From what I've observed the more primitives I have on the screen the higher the performance hit…
Lenny White
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How to render a rotated raster image with lesser aliasing
I am wondering about techniques for rendering a rotated and or scaled raster image. Currently I use the following algorithm
Render everything at double resolution and store the result in A
For each pixel in output image, assign it the value of the…
user877329
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