10
votes
Accepted
Why is AO considered Post-Processing?
This is a potentially confusing re-use of terminology. Ambient Occlusion is not in itself a post processing effect. Screen Space Ambient Occlusion is a post processing effect using the depth buffer to ...
6
votes
Accepted
Artifacts when gamma correcting
Short answer, set the precision of the image to a higher value.
Long answer,
When looking at a gamma correction curve, you can see that the lower values get changed much more, this means that the ...
- 1,605
6
votes
Making low discrepancy sequence noise textures, not LDS sample positions
In theory, it is possible to stuff every sample distribution into a texture to "pre-bake" it for fast access. The question is whether any of the results might be useful. For blue noise, this makes a ...
4
votes
Why is AO considered Post-Processing?
Ambient occlusion isn't a technique, but rather a concept. It can be implemented (and approximated) as a post-processing effect such as SSAO, SSDO, HBAO+, etc. @trichoplax gave a good answer, I just ...
- 1,363
4
votes
Accepted
Adding noise to gradient
It's generally a good idea to add noise like this when you're using a gradient, to avoid visible banding in the gradient, especially on smartphones. Often smartphone screens claim to be 24-bit colour ...
- 6,870
3
votes
Accepted
Deriving blur from real optical formulae
First we can calculate the physical diameter of CoC in the image plane, given the lens parameters. This equation is from Wikipedia – Circle of confusion:
$$
c = {|S_2 - S_1| \over S_2} {f^2 \over N(...
- 25.2k
3
votes
Screen space line anti aliasing
A gaussian blur with a small kernel size, like 3, would blur the line into adjacent pixels and may be all that is needed.
There is a technique called jump flooding that will turn an image like this, ...
- 3,354
2
votes
Accepted
What is the name for a film overlay where there is an array of crosses?
It’s called a Résau plate:
…a transparent sheet of glass or plastic engraved with a grid of crosshatches called fiducial markers. It was commonly used in film cameras (before the advent of digital ...
- 2,232
1
vote
Accepted
SSR/RTLR - hitting object/ending condition
The termination condition is that the ray passes through the surface represented in the depth buffer. To track this, you have to calculate the z position of the ray at the current step, and compare it ...
- 25.2k
1
vote
Accepted
Downscaling texture via mipmap [DirectX 11]
I found the problem. By zeroing the sampler description I implicitly set LOD bounds to 0. After adding
...
- 1,464
1
vote
What is a common approach to smooth structures in textures?
I don't have enough rep to add a comment so...
You could use a post process based anti-aliasing technique like FXAA or SMAA. Also, if performance is not a priority, you could go for SSAA. Another ...
- 110
1
vote
How does temporal reprojection work?
temporal reprojection works surprisingly well and simplistic with (in between) volume-marching (where rays scatter through a cloud of different density, with hard or smooth density-gradients)
validity ...
- 21
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