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4
votes
0answers
82 views

Proper way of consuming stratified samples in path/ray tracing

I'm working on a (toy-level) path/ray-tracer, currently trying to implement (and understand) improved sampling strategies. The obvious next choice after uniform random sampling would be stratified/...
1
vote
1answer
32 views

Is there a list of OpenGL extension support?

I am looking for a list that states which vendor does support which OpenGL extension. For example I wanted to use ARB_shading_language_include, which was accepted ...
0
votes
0answers
19 views

Nomenclature problem: what to call a graph format

(This may be the wrong group to ask in. Am open to suggestions.) I've been trying to graph a dataset of x1,y1-x2,y2 pairs. Each pair has an id and each id has information and style attached. So far ...
2
votes
0answers
78 views

The termination probability of Russian roulette in PBRT

As described in PBRT 14.5, the path tracer stops bouncing rays at a probability q, which is determined by the throughput of the path. ...
1
vote
0answers
40 views

Which is more important : Texel or Pixel rate? [closed]

I would like to know which is the most important ? More particularly in games or for the display of a desk (ex KDE Plasma, Windows 10 ...) ?
1
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0answers
21 views

Cannot use variable as texture sample value - HLSL DirectX11

I ran into strange problem. My HLSL VS won't compile for given lines: ...
1
vote
1answer
69 views

Is it possible to do color conversion on decoded video without getting it from GPUmemory to CPU memory?

Decoding video will result in different pixel formats on different GPUs and drivers. I have an application which can render (using OpenGL), only the RGB8 pixel format, therefore I need to do color ...
0
votes
0answers
36 views

Pixelated /aliased /blurry edges in volumetric rendering

I have been trying to implement a simple GPU based volumetric renderer, somewhat similar to described here. I conceptually understand most of the stuff, and implemented some code, but my results are ...
0
votes
0answers
21 views

Mathing gl_PerVertex declarations

Half a year ago the vulkan validation layer of matching the declaration of gl_PerVertex between shaders (e.g. vertex and geometry). Hence following pair of shaders now throws a validation error: <...
2
votes
1answer
112 views

GLSL Compute Shader doesn't run for large inputs

The shader takes an SSBO of Photons that have a position, direction, wavelength and intensity and each thread is responsible for tracing exactly one photon through the grid, where at each grid cell ...
0
votes
0answers
23 views

Customized editing of a 2D bitmap

Please excuse this basic question, as I'm new to computer graphics. Let's say I have a sprite that looks like below. I wish to programmatically transform the sprite such that the bitmap looks like ...
1
vote
1answer
99 views

Regular voxel grids and RTX accelerated ray tracing

I've been looking to play with ray tracing, starting with a simplest of minecraft clones (making something more akin to cave game, for starter). I figured I'd define a voxel as a primitive and then ...
1
vote
1answer
49 views

Wrapping normals around a sphere

I'm using a vertex shader to effectively wrap vertices on a sphere. Starting with world_position already after multiplying the vertex by the model transform matrix ...
2
votes
1answer
56 views

Async readback storage buffer

Every frame I dispatch a compute shader which write data in a storage buffer. The cpu needs to readback this data and use it. I would expect this to work : ...
0
votes
0answers
23 views

How can I create multivariable function plotting software

I have finished Dennis Ritchie's C book, and I would like to create my own plotting software for enhancing my programming skill,I want sources,books or anything to reach this goal.Thanks for answers.
0
votes
1answer
49 views

Microfacet BRDF artifacts

I've been trying to implement a microfacet specular BRDF based on the equations in Real Shading in UE4, but I'm getting weird ring-shaped artifacts in the highlights of rough surfaces: Here's the ...
3
votes
1answer
83 views

Rendering equation in terms of paths rather than directions

Path tracing seems to perform Monte Carlo integration where the space being integrated over is the space of paths (e.g. chains of rays) but the rendering equation is stated in terms of outgoing rays. ...
0
votes
1answer
41 views

Physically realistic received irradiance values given some BRDF?

I am trying to simulate the actual response of a camera given some object that is reflecting light. I've written a ray tracer, and have a BRDF that I need to use, and I have a camera sensitivity in ...
2
votes
0answers
43 views

Vertex positions from particle position

I have a question about Nvidia Flex or any particle based simulation in general: The particles are created by sampling the mesh, which can result in fewer particles than there are vertices in the ...
1
vote
0answers
78 views

Application of parallel transport in computer graphics and mesh processing

Does anyone know what applications has the computation of a parallel transport on a mesh? I'm talking about methods such as this one
1
vote
0answers
38 views

Where to find BRDF textures

I've read about measured BDRFs and models like cook-torrance have parameters that need to be set. It isn't hard to imagine that these parameters and the measured properties would vary from point to ...
2
votes
1answer
68 views

Offline path tracer produces a darker image than expected

I've been going though Peter Shirley's beginner raytracing books. Upon building the Cornell box and rendering an image, I get a much darker / dimmer image than expected. The color values are ...
0
votes
0answers
42 views

Moving a sphere in a basic ray tracer

I have written a really basic ray tracer. It generates primary rays and sets the colour of the pixel to the colour of the object that I have set myself. The code for which can be seen below. ...
1
vote
0answers
23 views

Mitsuba builds targets with scons but throws “undefined symbol” error when trying to render scene

I am trying to implement a custom add-on for Mitsuba, but when I use the Heightfield I have defined in another function call(WaveBrdfAccel) in main.cpp it compiles without any problems but when I try ...
3
votes
0answers
24 views

What expectations should I have of large (> 2 GB) file support in common mesh workflow tools?

I have an experimental workflow that involves very finely subdivided meshes, above the 2 GB limit where signed 32-bit integers stop working, which often causes problems for various tools. I would need ...
1
vote
1answer
66 views

light probe (for global illumination) placement techniques?

I'm learning light probes used for dynamic global illumination. I have a question regarding the placement of light probes, as based on most of the pictures I have seen, they seem to be placed ...
2
votes
0answers
45 views

Communication between vertex shader executions

Look at this vertex shader: ...
1
vote
0answers
41 views

Reddish tint with spectral renderer

I'm trying to implement a spectral path tracer and comparing results from my program with renders of the same scene done with pbrt and ...
0
votes
0answers
20 views

Visualize a mesh with sparse vertex counts

I have a mesh that records some integer information for its vertices. I expect this information to be quite sparse, with possible large variations. How could I visualize this on a colorscheme (e.g. ...
1
vote
0answers
179 views

Volume Rendering - Dataset not rendered correctly

So Im trying to implement a Volume Renderer mainly for medical images like CT-scans and MRI images using GPU raymarching. I'm using the book "Real Time Volume Graphics" and this tutorial as a refernce....
5
votes
3answers
98 views

What is the purpose of the projected solid angle $dA^\perp$ term in the definition of Radiance?

In the definition of Radiance, which according to PBRT is defined as flux per unit solid angle $d\omega$ per unit projected area $dA^\perp$ $$L_i=\frac{d\Phi}{d\omega\ dA^\perp}$$ My original ...
1
vote
0answers
40 views

Path tracing best materials to learn

i want some of your advices. To begin with i ve never studied computer graphics and i want to do a project with Path tracing which i didnt find the right materials to begin with. Is it recomeneded to ...
0
votes
0answers
17 views

how apply edge collapsing within selected surface

I'm using CGAL edge collapsing to remove edges on mesh and it's working successfully . But I want to run the edge collapsing process within selected surface on mesh viewer . I preview the Geomview (....
2
votes
1answer
78 views

Strange dark spot when lighting in deferred rendering PBR shaders

It's probably something obvious but there seems to be a strange issue with lighting in my pipeline. I'm trying to keep everything in world space at the moment for simplicity but cannot figure out what'...
0
votes
0answers
24 views

How to calculate rotational irradiance gradient vector?

I am reading the irradiance gradient on Greg Ward Radiance book and also this web page: Quoting from this web page: For normalized spherical coordinates the gradient is: The irradiance ...
2
votes
1answer
104 views

Downscaling texture via mipmap [DirectX 11]

I am implementing a post-processing effect in my DirectX 11 pet renderer. The post-processing pass is implemented by rendering a full-screen quad covered with texture containing original rendered ...
0
votes
0answers
46 views

Which method does the painting software use to deform the image so fast?

I tried to make my own painting software. I used OpenCV in my job so I use openCV here. I want to make a image deformation function like the following : use mouse click on GUI to deform the image. I ...
3
votes
1answer
61 views

Adding two fogs

When calculating fog along the ray we have two main part- transmittance and scattering. What happens when we have two different fogs? With different extinction and color? Both extinction and color ...
0
votes
0answers
27 views

Software Rendering Display Latency

I've been doing some reading as to how to reduce input delay on modern computing devices. A lot of my understanding from this comes from the VR research paper by Carmack explaining the numerous ...
3
votes
2answers
191 views

Triangle - Why is it the basic building block for complex shapes

I was recently learning about OpenGL and computer graphics development. I have a question regarding the usage of triangle as the basic building block, or basic shape to develop complex shapes. Is ...
1
vote
1answer
75 views

How was computer graphics libraries or gtk,qt programmed?

I am wondering how was first graphic or image libraries created,I know C and Python ,I want to create plotting application,and I cant imagine these libraries(QT,OpenGL,Vulkan) written by C,how can I ...
3
votes
0answers
71 views

How to separate, modulate, and reassemble spatial frequencies?

Background I am trying to create a node in Blender that would allow me to do what you would do with an audio equalizer but on the spatial frequencies of an image: A sort of panel with eight ...
3
votes
0answers
86 views

Can I use Path tracing together with Ray Marching?

So I'm trying to render participating media like clouds/sky/fog (Sky is the first step) etc. I had already implemented a normal pathtracer and I was thinking of extending it. But I heard terms like ...
0
votes
0answers
9 views

How do I set proper local rotation axis for A-posed arm joints?

I am currently teaching myself in character rigging while working on an educational project. So far I’ve been following the official character rigging tutorial from the maya learning channel on ...
0
votes
1answer
81 views

What are the i,j,k components of a 3d mesh on plot.ly (online)?

A 3d Mesh on plot.ly online graph maker (https://plot.ly/create/#/) takes 3 mandatory variables (X, Y, Z) and 3 optional variables (I, J, K). I understand that if I want to draw a cube that I then ...
0
votes
1answer
46 views

How to triangulate a simple 2d surface to generate a constrained surface trimesh

I want to split a couple of simple 2d forms into tri meshes. The meshes should conserve the original geometry and ideally I'd like a possibility to influence refinement vs. tris count. I have the 2d ...
3
votes
1answer
77 views

Origin of blurring and colour distortion in monochrome diagrams

I am analysing a large number of PDF files from scientific articles, all of which contain images which (I think) were originally monochrome ( black/white). The images have been extracted with Apache ...
1
vote
2answers
78 views

Techniques for rendering high polycount models

I would like to know what common techniques are used for rendering large models, when using rasterisation within a graphics API, for example OpenGL or Vulkan. For example if I had a model with >10 ...
-1
votes
2answers
86 views

Why does Cubemap have 6 individual textures?

I am learning about Cubemap and I learned that A cubemap is basically a texture that contains 6 individual 2D textures but my question is Why does it contain 6 individual texture ? and also I've read ...
0
votes
0answers
20 views

Newby - which computer language for video to video &/or 4-D to video

First post on forum. What's the simplest language / package for computer graphics that will do what i need? I have two projects in mind: One is to input a video (eg. from youtube) and process it ...

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