ComputeShaders

Compute shaders are shader programs designed for general-purpose GPU computation (GPGPU). They run on the GPU outside of the traditional graphics pipeline and typically write to memory buffers or images rather than producing a rendered frame. They are invoked by a dispatch that specifies a two- or three-dimensional grid of work groups, each containing multiple threads or invocations.

In the execution model, each thread executes the same shader code with a unique index identifying its data element. Threads within a work group may share memory and synchronize via barriers; synchronization across work groups generally requires separate dispatches or atomic operations. Programs can read and write to buffers and textures, using memory types such as global, shared (group), and constant memory.

Compute shaders are implemented in several graphics APIs, including OpenGL with GLSL, DirectX with HLSL, Vulkan, and Metal. They are compiled to an appropriate intermediate representation and bound via a compute pipeline. The local work group size is defined by the shader, and the total number of threads is the product of the local size and the number of work groups.

Applications cover data-parallel tasks such as physics and fluid simulations, image and video processing, numerical computations, Monte Carlo methods, and other GPU-accelerated workloads. Performance depends on data locality, memory access patterns, occupancy, and minimizing CPU-GPU data transfers. Debugging and portability require careful API-specific considerations.