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Remove clearly not visible vertices from a polygon

For a visibility algorithm I want to remove verts of polygon that are guaranteed not visible from a vert S. The idea is to remove pockets that points are on the backside of a plane formed by the vector n, the perpendicular vector between S and 0,…
rr84
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Workflow of the Naive Surface Nets algorithm

This question is comming from ComputerScience after suggestion I'm trying to understand the Naive Surface Nets algorithm which is related to surface generation out of Voxels. I've learned of it here So far I understood that the naive surface nets…
realvictorprm
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First steps towards CAD standard curve fitting

I am interested in building a program to accomodate the following workflow: A user begins with an arbitrary vector/CAD shape, which they wish to transfer onto paper without using a printer (there are both realistic and novelty reasons why this…
Will Goldie
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Why the BRDF of specular reflection is infinite in the reflection direction?

I know the BRDF of specular reflection is nonzero only in the reflection direction. But why it is infinite? A paragraph on page 36 of Advanced Global Illumination:
chaosink
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OpenGL - drawing icosahedrons and cylinders and combining them

I have drawn a cylinder and an icosahedron using OpenGL. Now, I need to use the icosahedron and the open cylinder to build a structure motivated by crystal lattices, where I use an icosahedron for each atom and a cylinder to connect each 2…
gambit20088
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Sending shadow rays to the sun

How is sun modelled for ray tracing rendering? Is it part of the scene, like a sphere with a centre in some far location or it is just considered as a point? Also regarding sending shadow rays to the sun, is it, again, sampling a sphere or just…
ali
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How to adapt diffuse/GI light mapper to directional light maps?

I have a working light mapper that captures global illumination. I evaluate a hemisphere when collecting the data and store the result in the texel. However, I want to support directional lightmaps so that I can more realistically light normal maps…
Steven
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Generation of stratified cosine weighted samples on hemisphere

I have had luck with cosine weighted hemisphere samples, and I know how to generate stratified uniform samples, but I wanted to experiment with combining the two. However, how do I correctly stratify the hemisphere when performing the cosine…
Steven
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Correcting my "look-at" matrix so that it works on non-camera objects?

I'm familiar with the "look-at" matrix and the goal of being able to rotate a Camera at a specific location towards a specified target. When I tell the Camera to look at some target, there're no issues. However, when some other non-Camera object…
code_dredd
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My perspective projection is messed up?

So I've been messing with perspective projection matrices recently. I used numpy and GTK/Cairo to make a very small Python renderer. I'm very confused with the results I'm getting though. I took this Homogeneous Coordinates technique from an online…
divx
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Bevel/Chamfer algorithm for arbitrary 3D mesh

I can't find any paper about a bevel/chamfer algorithm for 3D mesh. Bevel has a lot of special cases (corners, different bevel profile, bevel larger than a face). I am looking for robustness. Do you know any algorithm for this ? Thanks
user3918754
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Multiple buffers and calling glBufferSubData

In my project, for convenience I would like to use many buffers. Many buffers in my case means 50-100 terrain patches represented by buffers with vertex coordinates, normals, indices and maybe color. The magnitude of data would be, let's say 10^4…
remi000
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What are Jittering and Dithering

I've heard a lot about jittering and dithering but I would like to know more about those techniques, especially when used to avoid visible sampling in a fragment shader. What are the differences between both? When are they used the most? What's the…
MaT
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How to perform an image normalization after for example adding a constant to it?

I had some magical tasks to do on my lessons. I had to write an app which performs some operations: basic (adding, subtracting, multiplying a constant and a second image), geometric, filtering, histograms etc. There were ~50 tasks. I've made them…
Jacob
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How to get the GLFW_CONTEXT_VERSION_MAJOR value?

This code snippet: GLint versionMajor; glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2); glGetIntegerv(GLFW_CONTEXT_VERSION_MAJOR, &versionMajor); std::cout << "Version major:" << version << std::endl; prints "3" in my screen, but in the first line I…
Adrian
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