Questions tagged [compute-shader]
The compute-shader tag has no usage guidance.
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How do I tell what kind of shader an hlsl shader is by looking at the code?
How do I tell what kind of shader this is: https://github.com/aras-p/UnityGaussianSplatting/blob/main/package/Shaders/GaussianSplatting.hlsl
Among these options:
vs – vertex shader
ps – pixel shader
...
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OpenGL compute local size vs. performance
Does anybody know if using very small local sizes in compute shaders will hurt performance?
eg. If I do this in a shader:
...
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Partial Workgroup release of compute shaders?
When using compute shaders, some workgroups can be faster than others, for example when all invocations within one group go into the 'if' case, where on another workgroup the invocations go into the '...
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Workgroup size performance change?
I know, that when using compute shader, the invocations should to be grouped with respect to a multiple of the hardware minimum workgroup size (Nvidia 32, AMD 64). Otherwise cores are blocked. In case ...
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Rendering light balls: Where to do perspective calculations?
After rewatching Bisqwit's starfield renderer video, I've decided to try to rewrite the program in order to learn more about compute shaders and shader programming in general. My knowledge at this ...
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Do GL compute shaders trigger TDR if they crash. Not just timeout?
I'm getting a TDR trigger after 4ms with a GL4.3 compute shader. tdrDelay is currently set to 30 secs, this obviously isn't long enough to get a timeout with the default Windows 11 tdrDelay value let ...
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Opengl binding different mipmap levels of same texture2darray for use in compute shader. How to handle variable nr of levels?
So I want to make a compute shader that uses a coarse-to-fine approach.
As I have learned about open gl mipmap levels it seems they could be very useful.
However the only binding method which I have ...
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How to properly create textures using DSA for ImageTexture in OpenGL
For the old approach, generating a texture for the ImageTexture for compute shaders would look like this:
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GLSL trying to bind two different layers from the same texture array as images. Should it work and if so what am I doing wrong?
I am new at this particular site in the SE ecosystem, but not to computer graphics in general. If I'm in the wrong spot feel free to redirect me.
My question regards glsl programming and binding two ...
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Compute shader in DirextX: difference between four kinds of memory barriers
There are four kinds of memory barriers in DirectX. Their names and definitions are:
DeviceMemoryBarrier: Blocks execution of all threads in a group until all ...
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Does RWStructuredBuffer have built-in overflow protection in hlsl?
It appears that reads to indices outside the range of a ComputeBuffer always return 0, and writes to out-of-range indices do not cause any exceptions or runtime errors. Is there built-in range-...
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OpenCL WorkGroupSize compared to OpenGL compute shader WorkGroupSize
I've read, that OpenCL kernels are grouped like OpenGL compute shaders. That means, that you can define how many invocations should be executed within a workgroup. These invocations which are in the ...
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OpenGL compute shader workgroup synconization
I am calculating the Summed Area Table(SAT) of a texture with help of a compute shader in OpenGL.
The texture which needs to be summed, has a dimension size of more than my GPU supports (...
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Having trouble understanding advection from GPU gems fluid dynamics example
So I am trying to implement a fluid simulation, as described in Chapter 38 of GPU Gems.
I am also drawing heavily from the excellent implementation by Pavel.
Where I'm getting a bit stuck is with ...
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Is it possible to put matrix computation in Compute Shader?
With the library glm, we can do matrix computations on the CPU. However, the GPU is more suitable to do this. So what if I put the matrix computations in a Compute ...
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Bind shader storage buffer object for vertex input
I'm trying to learn about compute shaders, and as such decided to give it a go at implementing the particle system described in these slides: https://www.khronos.org/assets/uploads/developers/library/...
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On modern GPUs, what hardware do vertex/pixel shaders have access to that compute shaders don't?
Suppose that someone implemented rendering for a video game using entirely GPGPU apis, like compute shaders or CUDA.
Would it be possible to achieve the same performance as standard graphics pipelines ...
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Inter-Process communication in compute shaders
How do I write a code to facilitate common shared memory for communication between multiple shaders as well as processes within them in python?
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How do I view my vertex colors that I specified through the texture I've applied on my objec [OpenGL]?
I thought that if I used an image with a transparent background, I would still be able to see the colors I had specified in my vertex attribute buffer.
...
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Compute shader workgroups execution and size [closed]
I want to clarify how are workgroups executed on various GPUs, thus I have several questions. I know that different GPU architectures work differently, but I expect an answer YES if there is single (...
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SSAO with reconstructed depths yields strip artifacts
I wrote an ssao algorithm with compute shaders and view-position-reconstruction from the depth buffer. It works great for objects near by but results in strip or banding artifacts for large planes ...
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Compute Shader shared average value
Short Question:
How can i integrate a buffer variable in a compute shader over each pixel i.e. how can i ensure memory coherence in such a case?
Long Question:
I've written a deferred renderer with ...
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Offsetting value in shader causes unexpected/wrong logic
Let me explain what I am doing. I am trying to reduce the memory footprint of a voxel based algorithm by storing the voxel data as a hash map in an SSBO, as opposed to a 3D image.
I am visualizing the ...
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Unity crashes when running path tracing
I'm studying path tracing, at the moment I created a compute shader that aims to calculate the intersection of rays with meshes.
However, when I run the code the unity crashes, displaying a graphics ...
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Unity path tracing makes the pc crash
Good Morning. I'm testing Path Tracing techniques with unity, following this tutorial.
http://three-eyed-games.com/2019/03/18/gpu-path-tracing-in-unity-part-3/
But I'm in trouble.
Whenever I try to ...
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Performance difference in OpenGL compute shader vs Vulkan Compute Shader vs Cuda/OpenCL and others
I have been told there is no performance difference if you are skilled enough when it comes to gpu computing. And cuda only performs better because nvidia wants it to. I have also read graphic api's ...
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Is there an efficient way to achieve color blending in compute shaders?
What I want is a function like imageStore, but instead of replacing a value - applying a blend operation to it, e.g. addition. It is not possible to do something ...
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Mat4 that is written to a storage buffer in a compute shader has an altered value when read back
I am attempting to use a compute shader to calculate joint transforms for animations.
I use a loop to calculate the global joint transforms from the local transforms. Relevant code below:
...
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GLSL Compute Shader Setting "shared" memory buffer size
Is it possible to set the size of the shared memory of a compute shader workgroup from the host code? There is a way to do this in CUDA and I am suspecting that, since there is an GLSL extension to ...
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GL_OUT_OF_MEMORY Error when glDispatchCompute takes longer
I built a simple Ray Tracer which takes use of OpenGL's Compute Shader and traces ".obj" Files.
The results are passed to the Host-Program via glMapBufferRange after finishing computing.
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Is glDispatchCompute(a,b,c) any faster than glDispatchCompute(a*b*c,1,1)?
In my application, there is no inherent 2D or 3D structure to the computer shader instances. So having multiple dimensions doesn't benefit me semantically in any way. I am wondering, whether it still ...
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Using imageLoad/imageStore to perform atomic add
I have a rgba16f texture that I fill with values using nvidia GL_NV_shader_atomic_fp16_vector extension, which allows to perform ...
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Optimizing compute shader with thread group shared memory
I'm currently learning compute shaders and I'm trying to write an optimized Game Of Life. I have a first version working that uses a Shader Storage Buffer Object. I dispatch a thread per cell I want ...
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Using buffers correctly in OpenGL compute shaders
I'm re-writing an algorithm that I first wrote using matrix/vector operation into OpenGL kernels in order to try to maximiz the performances.
I have a basic knowledge of OpenGL, so I was able to get ...
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How to retrieve data from Compute Shader to CPU?
I want to retrieve data that has created by the compute shader but have no clue how it works. After researching a few forums and articles on how it should work and this is what I came up with.
Compute ...
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Reading from buffer versus calculating on the fly performance
I am creating a fast fourier transform algorithm for the compute shader - i am no expert on how GPUs really run optimally so thought i would ask here.
I have the option to calculate on the fly or ...
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Performance of Compute Shaders vs. Fragment Shaders for Deferred Rendering
I have written a deferred renderer that can use either a fragment shader or a compute shader to execute the shading pass. Unfortunately, the compute shader implementation runs slower. I'm trying to ...
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Groupshared memory and parallel reduction over multiple kernel dispatch
I am doing some parallel reduction and mostly following these nVidia slides. However they are not very detailed in places or I might be missing/misunderstanding something.
Edit 2:
While I figured ...
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Sharing memory between compute shader and pixel shader
I am relatively new to compute shaders and gpgpu in general so bear with me if i am missing the point somewhere.
The main thing i do not yet understand / see is how to get memory from a compute ...
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Only each third image in swapchain is being used, causing flickering
I've managed to write a "small" Vulkan program that outputs a solid color using compute shader directly to swapchain.
However, it doesn't work properly. ImageMemoryBarriers I've setup don't ...
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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 ...
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Compute shader textures compared 2D float4 arrays
I am wondering is there a difference in performance between using floating point textures as my 2D float4 array vs just passing in 2D float4 arrays?
2D float arrays eliminate the need to do texture ...
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What's the point of "work groups" for OpenGL compute shaders?
glDispatchCompute has the number of work groups as arguments.
What is the point of having work groups? How are they useful, compared to just having NxM independent pixel calculations with a known (x,...
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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 ...
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Can gl_WorkGroupSize be set outside the compute shader?
I am migrating code from CUDA to OpenGL compute shaders.
I could not find a way to set the local workgroup size outside the shader; is there a way to set gl_WorkGroupSize in the calling program like ...
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Controling order of execution of a (compute) shader on an array of vertices (data) in Vulkan
Is it possible to force Vulkan to execute a shader on vertices (data) in a semi-consecutive manner?
For example, if the data passed to the shaders as a binary tree, shader would process it one layer ...
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Feeding vertex data to a compute shader
I'm writing a CAD program in vulkan. In my current design, I have line paths represented as large vertex buffers for rendering. I would like to implement an algorithm for extruding the path outwards, ...
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Is a smaller local-size/threadgroup-size better for compute shader performance?
A compute shader defines the number of threads it requires to be executed.
This number can be called "local size" or "threadgroup size" according to the API, and be factored into 3 separate dimensions ...
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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 ...
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CUDA/OpenCL vs OpenGL compute shader for Path tracer
So I want to implement a path tracer and I am confused between GPGPU computing or using OpenGL's compute shaders. I've already implemented a raytracer using GL's compute shaders.
What are the main ...
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