Questions tagged [algorithm]
Questions about the rigorous usage of instructions used to solve a specific computer graphics problem.
191
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Why does monte carlo ray tracing perform better than distributed ray tracing?
I've heard that the quality of a monte carlo ray tracer (based on path tracing algorithms) is much more realistic than a distributed (stochastic) engine. I try to understand why, but I'm just at the ...
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How is anisotropic filtering typically implemented in modern GPUs?
Anisotropic filtering "retains the sharpness of a texture normally lost by MIP map texture's attempts to avoid aliasing". The Wikipedia article gives hints about how it can be implemented ("probe the ...
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What exact algorithm and parameters reproduce L-system plant growth figure in Algorithmic Beauty of Plants
I am interested in duplicating a figure (shown below, ch 1 fig 1.21) in the book Algorithmic Beauty of Plants. The book is available here
http://algorithmicbotany.org/papers/#abop
This image appears ...
14
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1
answer
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Why is it twice as expensive to make a noise function that can be tiled?
I've seen in several places that making Perlin noise loop seamlessly requires calculating it twice in slightly different ways, and summing the two results.
This Perlin noise math FAQ gives a formula:
...
12
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3
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How can I concentrate points in areas of higher curvature?
How can I distribute points over an implicit surface, to concentrate them more densely in areas of higher curvature?
I've considered adding points randomly and rejecting points not required based on ...
12
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2
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How is screen space ambient occlusion implemented?
I do not understand the explanation from wikipedia.
For every pixel on the screen, the pixel shader samples the depth values around the current pixel and tries to compute the amount of occlusion ...
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11
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1
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Optimal memory access when using lookup tables on GPU?
I'm exploring isosurface algorithms on GPU for a bachelor's project (specifically concentrating on just binary in/out voxel data rather than real-valued fields). So I have a CPU implementation of good ...
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Shading: Phong vs Gouraud vs Flat
How do they work and what are the differences between them? In what scenario should you use which one?
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Modelling Young's double slit experiment
Young's double slit experiment is very simple to set up and simple to explain, but it is an example of both diffraction and interference, neither of which are modelled by conventional raytracing.
It ...
10
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1
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Strategy for connecting 2 points without intersecting previously drawn segments of curves
I have to connect point pairs without intersection.
Let's say I have two given points that I connect with a segment of a curve. Then again two new endpoints are selected and these new points have to ...
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Why are oct trees so much more common than hash tables?
When reading papers I commonly find Oct tree implementations of geometry representations to sort the data. However whenever I think about the problem hash tables seem better overall.
Hash tables have ...
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Understanding Jump Flooding Algorithm (JFA) for Voronoi Diagrams
I'm having trouble understanding the JFA. As far as I understood the algorithm, it walks log(n) times through every pixel (no matter if it is a seed or not) and looks at that pixel's neighbors in $(x+...
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How should I fill a shape consisting of Bezier curves and straight lines?
I have been working on a graphics library for some time now and have gotten to the point where I have to draw Bezier and line based fonts. Up to this point I am stuck with this:
The green lines are ...
- 93
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Perturbed image texture implementation from renderman language
I am trying to implement (in C#) an image perturbation algorithm presented in the book "Texturing and modeling - K. Perlin et al" (page 91 if anyone has it), which distorts an image.
The following ...
- 91
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Changing image so it would look like through colorful glasses
I am currently working on some simple pixel shader in HLSL. I send to shader texture and I want to make it more colorful (something like in the picture below).
In the picture 1 there is original ...
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