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1500 questions
8
votes
1 answer
NURBS knot multiplicity
In Splitting of NURBS curves there the answer relied on "maximum knot multiplicity". In order not to mix-up different topics I would like to kindly ask to answer it in another question: what is this "knot multiplicity" all about?
Ecir Hana
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8
votes
1 answer
How to improve on bilateral upsampling in real time scenarios
It is a well known "standard" to use bilateral upscaling when it comes to comes to combine a low resolution target and an higher res one.
I have personally noticed that using the basic algorithm (with weights based on depth differences between high…
cifz
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8
votes
0 answers
Code runs differently on different hardware
I wrote a 2D fluid-solver in OpenGL (code here) some time back.
While it runs flawlessly on my onboard Intel GPU,
the simulation very quickly "blows-up" when same code is run using nvidia card :
In the second picture, the fluid is being…
nilspin
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8
votes
2 answers
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 vertex lights + SHs and an additional pass for each…
Felipe Lira
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8
votes
1 answer
How is motion blur implemented in modern realtime renderers?
When realtime renderers (such as 3d games) have motion blur, how is it usually implemented?
I think I've heard something about needing to have motion vectors for each pixel but I'm not sure about that and not sure how it would be used.
Alan Wolfe
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8
votes
2 answers
Can (and how so) shaders paint screen pixels beyond those that occupied by the shaded mesh?
I have some experience programming geometry and compute shaders - but never adventured myself in really playing with the fragment shaders. Currently, I am trying to better understand how they work and their potential. One of the things I have read…
AndrewSteer
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8
votes
1 answer
Role of PDF of Uniform Random Sampling in a path tracer
I am trying to implement my own path tracer but before arriving to the question I want to give you a short overview:
In the implementation of the rendering equation I use some particular technique in order to sample surfaces. For example: when one…
Tarta
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8
votes
2 answers
Why is the CMYK space four sided in chromaticity charts
In chromaticity charts the CMYK color space is usually four-sided. I've lately had to read quite a few charts and it suddenly dawned to me that I don't really understand why. It has just not been something I've needed to think about until…
joojaa
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8
votes
1 answer
How does everyone count "Rays per Second"?
Recently I'm developing a Monte-Carlo path tracer. To measure my tracer's performance, I decided to implement a simple mechanism to count how many rays can it trace in a second. Then here comes the problem, there are two ways to define a single…
D01phiN
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8
votes
1 answer
Gamma setting in games - Why 3 icons?
Whenever I try to adjust gamma settings in a game, I am shown three different icons and usually asked to make sure the left-most one is barely visible.
Example:
What are the other two icons for?
Simon Farshid
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8
votes
1 answer
Matching a virtual camera to a physical camera
Say I've got a photograph of a scene, and measurements for part of it (eg. a room where I know the dimensions of the walls). Assuming a rectilinear lens, how would I go about setting up a virtual camera so that 3D objects are rendered as if they…
Mark
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8
votes
1 answer
Parametrize set of unordered points in 3d space
Let's assume that we have some set of points in 3d space sampled from some arbitrary surface, without self intersections and mostly flat. Is it possible to get any parametrization over this set of points? And if it is - how?
My first idea was to…
Ibraim Ganiev
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8
votes
2 answers
What methods/technologies to reduce required performance for virtual reality are there?
I'm interested in virtual reality, but according to some sources, less than 1% of computers in use today have the necessary performance to run modern VR games, granted many of them are not intended for gaming, that's still a huge barrier for the…
Syzygy
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8
votes
2 answers
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 or rasterization perspective?
Alan Wolfe
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8
votes
1 answer
How are we supposed to fix brightness with square roots?
I recently watched this video that talked from a physics perspective how most of the ways we deal with color on the computer is incorrect because brightness is on a logarithmic not linear scale. Being a novice graphics programmer I want to know how…
J.Doe
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