Questions tagged [cuda]
The cuda tag has no usage guidance.
18
questions
0
votes
0
answers
40
views
Noise darker in one quadrant
I have tried mapping a simple 3D Perlin noise to the surface of a sphere and the sphere always appears darker in the first quadrant. Can anyone help me figure out why this code be? I have tried a ...
1
vote
1
answer
701
views
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 ...
2
votes
1
answer
2k
views
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 ...
1
vote
1
answer
156
views
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 ...
3
votes
1
answer
193
views
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 ...
2
votes
0
answers
660
views
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 ...
1
vote
0
answers
487
views
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....
2
votes
1
answer
304
views
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 ...
1
vote
0
answers
54
views
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 ...
4
votes
2
answers
717
views
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 ...
3
votes
1
answer
114
views
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 ...
2
votes
1
answer
4k
views
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 ...
2
votes
1
answer
4k
views
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 ...
3
votes
0
answers
333
views
Is Nvidia's delta color compression supported in CUDA, or with DirectX UAVs?
Nvidia discusses their lossless delta color compression is on its fourth generation in Pascal, and that it transparently saves bandwidth behind the scenes for rendering workloads. AMD has a similar ...
9
votes
2
answers
4k
views
A recent approach for subsurface scattering
I read "A Practical Model for Subsurface Light Transport" and "A Rapid Hierarchical Rendering Technique for Translucent Materials". If I understand correctly, the former does not consider the case ...
9
votes
1
answer
4k
views
Compute Shader vs CUDA/OpenCL
So I just recently learned about the Compute Shader and it looks from what I have picked up the same idea as parallel programming you would do with CUDA or OpenCL, but in the shader pipeline.
If I ...
3
votes
1
answer
345
views
GDDR5 vs. DDR3 for learning GPU programming on a limited budget?
[Please (kindly) let me know if this is not the place for this question]
I'm hoping to learn about GPU programming, but as a college student, I've a quite limited budget. I'm wondering whether I ...
4
votes
0
answers
338
views
CUDA cuMemcpuHtoD vs cuMemcpy2D
Asking it here and not on SO as it seems to be appropriate question for CG.
I am learning NVIDIA NVENC API.The SDK supplies a sampled called "NvEncoderCudaInterop" .There is a chunk of code which ...