Computer Graphics Stack Exchange
Computer Graphics Stack Exchange

Most Popular

more tags
1500 questions
8
votes
1 answer

Proper way to handle diffuse + refraction + reflection rays in path tracing?

Let's say we are path tracing and that there is an object which has some amount of diffuse reflection, and some amount of specular reflection. What is the best or correct way to handle that in the path tracer? Looking at smallpt…
Alan Wolfe
  • 7,801
  • 3
  • 30
  • 76
8
votes
1 answer

Is this Russian roulette code correct?

I'm using www.scratchapixel.com among other resources to help me learn how to implement a renderer. I am looking at the following code from this page where a packet of photons moving through a material is being considered. For each photon packet,…
PeteUK
  • 700
  • 5
  • 13
8
votes
2 answers

Is it expected that a naive path tracer takes many, many samples to converge?

I have a naive diffuse/emissive material path tracer implementation (pinhole camera) and am seeing it take a very large number of samples per pixel to converge - like probably in the millions - and was wondering if that was normal for "naive" path…
Alan Wolfe
  • 7,801
  • 3
  • 30
  • 76
8
votes
3 answers

How to denoise video?

Video noise is random and not correlated in time. I assume, the best method is using wavelet denoise in this case, right? If yes, how is wavelet denoise implemented for video? Is there something to consider in order to apply the calculation to the…
p2or
  • 596
  • 1
  • 7
  • 15
8
votes
1 answer

How to correctly render visible spectrum with uniform intensity?

I'm trying to get the correct representation of visible spectrum to render on the screen. My current progress is with using CIE 1931 standard observer color matching functions analytically approximated by the equations given in this paper. Current…
Ruslan
  • 416
  • 3
  • 13
8
votes
1 answer

How much precision (half, float, double, etc) is enough for a Color class?

While doing some reading on how real-time applications handle color under OpneGL, I noticed that some examples implemented Color as a collection of 4 floats, while others used 4 doubles. I have even seen some vertex-compression examples in the game…
AndrewSteer
  • 265
  • 1
  • 5
8
votes
1 answer

What is occlusion?

Occlusion "is the effect of one object in a 3-D space blocking another object from view." With this definiton in mind I cannot understand sentences like: The interior of a tube is typically more occluded (and hence darker) than the exposed outer…
Joey
  • 627
  • 1
  • 6
  • 14
8
votes
2 answers

Why random monte carlo sampling instead of uniform sampling?

Why is it that it's so common to use monte carlo randomized sample locations, instead of uniform sampling? I'm assuming that taking randomized samples gives some benefit but I don't know what they could be. Is anyone able to explain the advantage of…
Alan Wolfe
  • 7,801
  • 3
  • 30
  • 76
8
votes
2 answers

Are vertices reprocessed per-poly for indexed meshes?

I've been digging a bit into what actually happens at a hardware level on the GPU, and found NVidia's Life of a triangle which explains the pipeline pretty well, at least for green boxes. One thing I wasn't clear on is what happens with indexed…
russ
  • 2,392
  • 9
  • 18
8
votes
1 answer

Label Placing for thousands of objects with OpenGL

Question How to manage data (GPU,CPU) for dynamic label placement in 3d for thousands of objects (OpenGL)? Details objects: count: 2k-10k type: points/quads labels: bilboarding data: text and colors placing: labels are not overlaping more on…
BPiek
  • 307
  • 1
  • 7
8
votes
3 answers

What algorithm is used in the animation of the uTorrent 's "About window"?

In a recent version of uTorrent , if you open the About Window, you will see an animated background , which is kind of waves that go on forever. How can this be achieved? Is this kind of a well-known algorithm/class of algorithms? Thanks.
Wfi Okly
  • 103
  • 5
8
votes
1 answer

Apply distortion to Bézier surface

I am trying to simulate the image warp effect, that is used in Adobe Photoshop. The rectangular image is warped according to a cubic Bézier surface (in 2D, all Z components are 0). Having any Bézier surface, vertical distortion $d \in[0,1]$ can be…
Ivan Kuckir
  • 183
  • 3
8
votes
1 answer

Computational Geometry - Triangulation

I'm trying to triangulate complex 3D objects, that may have holes in them. Now I tried going over the problem myself, after a few hours I didn't get anything that would work all of the time, so I've been searching around and without much luck. Does…
Aaron
  • 81
  • 1
8
votes
2 answers

Algorithm to find the center of a Bezier curve

I need to find the center of a Bezier curve to rotate it. I have a list of all points (control points, beginning and end, all points on the curve itself). How would I go about finding it's center?
user4656
  • 81
  • 1
  • 2
8
votes
1 answer

Why does checkerboard pattern on a computer screen appear with a yellowish tint?

This question was originally asked on Physics, then moved to Cognitive Sciences. Consider the following image: You might want to display the image in a new page, in case it gets resized for mobile displays. On the top half, there is a pixel-sized…
IS4
  • 183
  • 1
  • 4
1 2 3
…
99 100