forge-uniforms-and-motion

Pass per-frame data to GPU shaders in SDL3 by defining a Uniforms struct with std140 layout and calling SDL_PushGPUVertexUniformData before you begin the render pass. This efficiently updates time, aspect ratio, and matrices.

Push uniforms are ideal for small, frequently changing data like time or simple matrices, whereas GPU uniform buffers handle larger per-frame data sets. Push uniforms map directly to HLSL registers for quick shader parameter updates.

SDL3 shader uniform alignment mismatches occur when your C++ Uniforms struct does not follow std140 layout rules. Defining the per-frame struct with proper std140 alignment ensures it correctly matches shader cbuffers.

Use SDL_PushGPUVertexUniformData for time-based animation when you need to update small, dynamic shader parameters each frame. Populate the struct with elapsed time and push it prior to calling SDL_BeginGPURenderPass.

Yes, push uniforms support time-based animation, dynamic colors, and simple transform parameters. You populate a per-frame Uniforms struct on the CPU and push the data to the GPU before rendering to drive these visual changes.

Yes, SDL3 GPU supports mapping uniform slots to HLSL registers. This mechanism allows you to push per-frame shader data efficiently and ensures the GPU correctly receives your dynamic transformation matrices and parameters.