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Ambient occlusion of a sole object in a scene

So, the german wikipedia states about ambient occlusion:The ambient occlusion method is based on the assumption that an object, a set of objects or an entire scene is surrounded by a unit sphere of light. Now, let's suppose we've got a scene in…
yot
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Using multiply and accumulate of 4x4 matrices for ray-triangle intersection tests on GPU

Is it possible to gain performance boost using new 4x4 MAD from NVIDIA'a tensor cores for ray-triangle intersection tests? Really there are two questions: Is it possible to modify some of the ray-triangle algorithms (say, Möller-Trumbore algorithm)…
Tomilov Anatoliy
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PDF when sampling from Rectangular Area Lights

So I was reading up on how to sample Rectangular Area lights, and the procedure is pretty straightforward. That is, I can get random points using the equation. $ p = X_o + \epsilon_1V_1 + \epsilon_2V_2$ Where $X_o$ is my corner point for the…
gallickgunner
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Should direct illumination and path tracers render the same scene equally bright?

I am using the book Ray Tracing from the Ground Up by Kevin Suffern to build my first ray tracers in Java. Based on the theory, I expected that direct illumination and simple path tracers render the same scene equally bright (that is, when the…
Jeroen
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Deriving blur from real optical formulae

Looking at the Wikipedia page for Circle of Confusion, and at such posts as this one, I completely understand how to calculate the values for near, far, focal planes and hyperfocal distance. I am also aware of the Zeiss formula for my desired…
SgerbwdGwyn
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What is OpenGL's paradigm?

OpenGL is not object-oriented, but more like "switches you turn on"? Like glEnable(...); list_id = glGenLists(1); glNewList(list_id, GL_COMPILE); glBegin(GL_TRIANGLES); ... It seems like one's turning on switches on some machine which is contained…
mavavilj
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MipMaps for Signed Distance Field

Is there some algorithm that keeps details when creating mipMaps for SDF? For example group of 4 pixels when only one is above threshold will lose this pixel with bilinear and creating mipMaps with 'max' of those values will add noise. When purpose…
Derag
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How to estimate what GPU (2D/3D/none at all?) is necessary?

I have to do some operations on 2D grayscale images. The "normal" stuff like moving, alpha blending and resizing, but also "3D like" operations: Perspective projection, rotation around any axis (x, y, z). All this happens in an embedded system,…
mic
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Path Tracer - implementation questions

so I am currently in the middle of implementing a path tracer for my bachelor thesis. And so far I have understood and mapped the general flow of the program except for 2 things. Note that I'm using OpenCL and will be using OpenGL-OpenCL interop for…
gallickgunner
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Direct3D Global Atomic Issue

Recently I ran into an odd issue with some of my DirectX11 DirectCompute code when trying it on an AMD GPU for the first time where as on a NVIDIA one it had worked fine all through development. The fact that this only appeared on AMD either means…
Lemon Drop
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Computing a lookAt matrix by passing a vec3 to a camera object

I am following this tutorial on how to implement a first person camera. So far I was able to implement the entire (C++) class in TypeScript and it works as it is supposed to. Problem What I was not able to implement is a system which takes the…
チーズパン
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Degenerate case of normal computation in marching cubes

I'm implementing the marching cubes, reference is this. I managed to get the geometric reconstruction (the mesh) however I do struggle with the normals. In section 4 they explain the gradient can be firstly estimated using central difference using 8…
user8469759
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Is a branched discard to be avoided

When a simulating a camera, I may run into the situation that a black elliptic border is needed (rather than a rectangular image). In this case I have the option to discard the fragment in the fragment shader or draw it with a black color.…
Tare
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Variance of estimator (Monte Carlo Integration)

So I was reading this paper by Lafortune, "Mathematical Models and Monte Carlo algorithms" and in it he writes. We have a function or integrand I we want to estimate given as, $I = \int f(x) dx$ We then have a primary estimator for this…
gallickgunner
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How to align Ray Marching on top of traditional 3D rasterization?

I'm trying to apply raymarching on top of 3D rasterization, ordering what 3D object gets displayed based on the depth of a rasterization pass and the raymarch depth. After getting the transform right for position (using the information here) I was…
Krupip
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