opencl

I wan't to do some calculated pixelart with OpenCL and display this directly on the display without CPU roundtripping. I could use interoperability of OpenCL with OpenGL and write to the texture-banks of the GPU and display the texture with OpenGL. I was wondering what would be the best way to do this, since I do not need any 3d stuff, just 2d pixelart. The best way would be to use OpenCL/OpenGL interop, if your OpenCL implementation supports it. This allows OpenCL to access certain OpenGL objects (buffer objects and textures/renderbuffers). You won't be able to directly access the default

Unlike barrier() (which I think I understand), mem_fence() does not affect all items in the work group. The OpenCL spec says (section 6.11.10), for mem_fence() : Orders loads and stores of a work-item executing a kernel. (so it applies to a single work item). But, at the same time, in section 3.3.1, it says that: Within a work-item memory has load / store consistency. so within a work item the memory is consistent. So what kind of thing is mem_fence() useful for? It doesn't work across items, yet isn't needed within an item... Note that I haven't used atomic operations (section 9.5 etc). Is

I have written a simple program that does autocorrelation as follows...I've used pgi accelerator directives to move the computation to GPUs. //autocorrelation void autocorr(float *restrict A, float *restrict C, int N) { int i, j; float sum; #pragma acc region { for (i = 0; i < N; i++) { sum = 0.0; for (j = 0; j < N; j++) { if ((i+j) < N) sum += A[j] * A[i+j]; else continue; } C[i] = sum; } } } I wrote a similar program in OpenCL, but I am not getting correct results. The program is as follows...I am new to GPU programming, so apart from hints that could fix my error, any other advices are

I am trying to use create a subBuffer to read in a chunk of the buffer created from a 1-D vector. This is the code I am using: d_treeArray = clCreateBuffer(context, CL_MEM_READ_WRITE, sizeof(cl_uint)*total,NULL,&err); cl_buffer_region region; region.origin = 0; // This works //region.origin = 4; // This doesnt work region.size = 10*sizeof(cl_uint); d_subtreeArray = clCreateSubBuffer(d_treeArray,CL_MEM_READ_WRITE,CL_BUFFER_CREATE_TYPE_REGION, &region, &err); if(err != CL_SUCCESS) { std::cout << "Cannot set buffers" << std::endl; exit(1); } Now when I give the region.origin as anything other

I have been working on an c/c++ OpenCL solution for the past few weeks now. For my solution, I need to pass a class from my CPU(Host) to GPU(Device). When I try to pass the class as an argument it gives an error "Unknown Type-Identifier Class". My doubt whether OpenCL on Intel Platform does it allow us to pass a class to kernel or any work around is available for it. In CUDA I have seen some examples and it works perfectly fine for the platform. However, with respect to OpenCL I am not able to find any references and No examples related to this query. I would be really thankful to any help

I have an array like this: 0 0 0 1 0 0 0 0 5 0 0 3 0 0 0 8 0 0 I want every non-zero elements to expand themselves one element at a time until it reaches other non-zero elements, the result is like this: 1 1 1 1 1 1 5 5 5 5 3 3 3 3 8 8 8 8 Is there any way to do this using thrust? Is there any way to do this using thrust? Yes, here is one possible approach. For each position in the sequence, compute 2 distances. The first is the distance to the nearest non-zero value in the left direction, and the second is the distance to the nearest non-zero value in the right direction. If the position