A Compute Shader is a program that runs on the GPU, designed for general-purpose parallel computation. It enables leveraging the immense processing power of graphics hardware for tasks beyond traditional rendering, like physics simulations or Image Processing, optimizing performance.
Example
Compute shaders typically operate on a grid of work groups, where each invocation (thread) processes a small portion of data in parallel. A common use case is processing large arrays or textures.
Here is a conceptual example demonstrating vector addition in GLSL:
// Example: Vector Addition Compute Shader
#version 450
layout(local_size_x = 256, local_size_y = 1, local_size_z = 1) in;
layout(std430, binding = 0) buffer InputA { float data[]; } a;
layout(std430, binding = 1) buffer InputB { float data[]; } b;
layout(std430, binding = 2) buffer OutputC { float data[]; } c;
void main() {
uint index = gl_GlobalInvocationID.x;
c.data[index] = a.data[index] + b.data[index];
}
This shader takes two input buffers (a and b) and writes their element-wise sum to an output buffer (c). Each thread processes one element, demonstrating efficient parallel data processing.