# All Questions

27 views

### Procedural terrain: What's the best approach to calculate noise in the GPU?

A few years ago I started creating a procedural planet engine/renderer for a game in Unity, which after a couple of years I had to stop developing due to lack of time. At the time i didn't know too ...
48 views

### Why are depth buffer values clamped to (0, 1)?

This is a simple question. I know that in OpenGL or other graphics API, the values stored in the depth buffer are automatically clamped to (0,1). I just want to know why people do this instead of ...
13 views

### How can I register an articulated model to noisy predictions?

Given point sets $Y$ and $M$, I'd like to register articulated $M$ to $Y$ without changing the edge distances of $M$. The point correspondences between $Y$ and $M$ are known and points have a fixed ...
26 views

### How to handle GUI in a path traced renderer?

This isn't a pure CG question but it's more of a programming one related to CG. The main problem that occurs is both the GUI and the rendered scene need to be drawn regularly by swapping buffers. If ...
55 views

### Generate mesh from pointcloud data

Given point-cloud data : For example. position + color and normal. What will you use to generate mesh of this data and keep reasonable quality for real time cases ? Additional info to consider: ...
22 views

### Speed of different access methods reading a picture

Suppose there is a cpu with a cache line of 64 Bytes. Now you need to access all the data of a 2D image stored in the main sequence of the line by pixel. The image size is 1024*1024, of which there ...
22 views

### Targeted pixel updating in Java GUI

What’s the best approach for targeting specific pixels of a displayed GUI image in Java? For example writing a real-time mouse highlighter, editing certain pixels without refreshing the entire frame.
2k views

### Why normal map is blue and purple in color?

I am learning about normal mapping I understood that RGB values converted into XYZ,but my question is how it is converted, and why the normal map is blue and purple in color ?
42 views

### Which of these 2 general designs for a game engine is better?

I have roughly seen 2 different ways rendering engines are commonly handled (there could be more). And was wondering which general design is better for a general purpose engine. Central Handler ...
137 views

### PBR missing rim darkening on non metallic rough surfaces

If you have a dielectric (non metallic) sphere with a large roughness value (say, 0.95), and put it in a lighting environment that has a constant onmidirectional lighting value (such as 0.5) Cook-...
32 views

### Why the interval for which there are more number of steps is chosen while implementing DDA Algorithm?

I was studying the DDA Algorithm and learnt that initially we calculate both the x-difference and the y-difference between the start and the end points of the given line, and if dx > dy, we choose ...
177 views

### Why does graphics speak of “dielectrics” rather than insulators?

For example, Filament's documentation at https://google.github.io/filament/Filament.md.html uses the term "dielectrics" when contrasting nonconductors to conductors, which it calls "metallics". And ...
36 views

### What does “region to be shaded” mean in the PCF paper?

I am reading the percentage closer filtering (PCF) paper by Reeves, W. et al. (https://graphics.pixar.com/library/ShadowMaps/paper.pdf). At at section 3.2, it mentioned that "each shading calculation ...
43 views

### CPU load in games - what is the GPU/DirectX doing to make CPU load higher?

More of a question about what's possible in DX. Some people have reported that when running games on higher settings they get less CPU load but when dropping the settings the CPU load increases. ...
47 views

### How do we approximate the integral of the measurement contribution function in Metropolis Light Transport?

In Metropolis Light Transport, we need to approximate the integral of the measurement contribution function. I've read that this can be done using a traditional approach like path tracing. However, ...
41 views

### Deciphering Affine/Projective Transformation Code

I've spent about 2 days trying to understand this piece of code (from here) that applies an affine/projective transformation to an image. I will link bits of the code that I'm struggling to understand ...
42 views

### What is wrong with this GGX sampling function?

I wrote a small Shadertoy path-tracer a few days ago to teach myself PBR transmission/reflection, and I decided to use Heitz's microfacet sampling model since it's cleaner than the one in PBRT. I'm ...
52 views

### Repeating alpha over/under operation multiple times

I have two RGBA colors in linear [0..1] space, src and dst and I want to alpha blender src ...
53 views

### How to visualize and programmatically work with huge point cloud

I have created a quite large point cloud with about 800M RGB points. The exported .ply file is about 12GB large. The commercial software I used to create it can render the cloud very smoothly on my ...
63 views

### Non real-time rendering on Unity3D

I made an audio visualizer using Unity3D (you can see it here) but I am not satisfied on the video quality, as the compression destroys the graphics. I recorded the screen during a real-time rendering....
78 views

### How can we convert a probability density according to solid angle to a density according to area?

In Chapter 14.5.3 of Physically Based Rendering - From Theory to Implementation (3rd edition), the authors claim that a probability density $p_\omega$ according to solid angle can be converted to a ...
50 views

### Best way to clear a framebuffer image without drawing?

So I have a framebuffer image which later acts as input to a compute shader, and some frames there is geometry drawn to the framebuffer, but some frames this is not necessary. The thing is, in my ...
39 views

### Generating Mip Maps For A Cube Map

Let's say I have a cube map that has a resolution of 256x256 for each face and I want to generate mip maps for it using a box filter. It's tempting to just mip each face individually, cutting the ...