Questions tagged [cuda]
The cuda tag has no usage guidance.
21
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How is Shader Execution Reordering implemented under the hood?
I am writing a software path tracer from scratch in CUDA (for learning purposes, without resorting to any higher-level graphics API like OptiX), and it is well-known that path tracing can have ...
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Why is my ray tracer not accelerated by CUDA?
Summary: I ported a simple path tracer smallpt into CUDA but the performance doesn't boost.
reproduce results:
build and run the CPU version:
...
- 183
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0
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74
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What performance to expect from an optimised pathtracer?
I am currently writing a fairly basic pathtracer as a compute shader in C++/CUDA, which has been running on a GTX 1080, and I have noticed that when logging some statistics, I get around ~1 billion ...
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What is in a GPU driver?
There are 3 kinds of code that are contained in a GPU-utilizing program:
CPU code.
CPU-to-GPU or GPU-to-CPU bridge code. This is what DirectX actually is.
GPU code. In NVidia speak, this is called a &...
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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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2
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1
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6k
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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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196
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Why is the image from the CUDA version not as sharp as the CPU version?
I am extending Roger Allen's Ray Tracing in One Weekend in CUDA (and also here) by following Peter Shirley's Ray Tracing: The Next Week; specifically Image Texture Mapping.
The image I obtain from ...
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3
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207
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Why does my image has a square pattern in cuda path tracer?
I am writting a path tracer in cuda following the Shirley's book. I am having a square pattern as an output.
The size of the block change if I change the block dimensions. For this image, the block ...
- 461
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0
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1k
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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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How to display image from CUDA / What API to port my project to for real-time raytracing?
I started a raytracing project using the python numba library which provides a just-in-time compiler for CUDA kernels. When the scene is rendered my result is a 1920 x 1080 x 3 RGB array in GPU memory....
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476
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Strange sphere reflection effects in ray tracing project. I cannot figure out what causes them
I started a ray tracing project in Python. I made a CUDA kernel and a trace() function for each pixel. It works perfectly when calculating intersections, shadows and lambert shading, however when I ...
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59
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Why cache working set per multiprocessor for texture memory in Nvidia has a variable size?
I saw it here https://docs.nvidia.com/cuda/cuda-c-programming-guide/index.html#features-and-technical-specifications__technical-specifications-per-compute-capability , I don't know if it also happens ...
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1k
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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 ...
- 299
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120
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How to avoid slowdown with 25-30 students running simple GPU kernels on 4 GeForce GTX 650 Ti s?
So I'm teaching crash-course in CUDA that teaches students how to write good GPU code (CUDA 7.5 in this case). They kernels they will be running will do matrix multiply on 2048x2048 floating point ...
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Can you do GPGPU on integrated graphics like Intel HD 630 on Core i3?
The Core i3 says it has "integrated graphics" with Intel 630.
Does this mean it is like a mini GPU?
In which case can use things like CUDA to speed up C sharp programs?
Is there much software that ...
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