Commands

GPU work is recorded in a CommandBuffer borrowed from its CommandQueue. Recording preserves command order, but execution begins only after submission.

Record and Submit Work

Borrow a command buffer from the queue that should execute the work:

CommandBuffer commandBuffer = context.ComputeQueue.CommandBuffer();

commandBuffer.Transition(texture, default, TextureLayout.Undefined, TextureLayout.Storage);

commandBuffer.SetPipeline(pipeline);
commandBuffer.SetConstantBuffer(buffer, 0);
commandBuffer.Dispatch(groupCountX, groupCountY, 1);

commandBuffer.Transition(texture, default, TextureLayout.Storage, TextureLayout.Sampled);

commandBuffer.Submit();

A command buffer is queue-owned and valid only for the current recording. Set the matching pipeline before binding state or issuing work, submit it immediately, and never store, reuse, or dispose it.

Track Completion

Submit() returns a TimelineValue. Use IsCompleted only for a non-blocking status query. Call Wait() when CPU code must observe GPU results, including command-buffer downloads. To order queues without blocking the CPU, pass the producer value to the consumer submission. See Synchronization.

Record a Render Pass

Transition attachments before beginning a render pass:

commandBuffer.Transition(texture, default, TextureLayout.Undefined, TextureLayout.ColorAttachment);
commandBuffer.BeginRenderPass([ColorAttachment.Clear(texture, default)], null);

commandBuffer.SetPipeline(pipeline);
commandBuffer.SetVertexBuffer(buffer, 0, 0);
commandBuffer.Draw(vertexCount, 1, 0, 0);

commandBuffer.EndRenderPass();

BeginRenderPass initializes viewports and scissors from the attachment size. Set them afterward when rendering to a smaller region.

Transfer Data

Command buffers can upload, download, copy, and resolve resources. These operations can be batched with later GPU work.

Texture transfer commands do not change texture layouts. Record the required CopySrc, CopyDst, ResolveSrc, or ResolveDst transitions around them.

For simple one-off transfers, Buffer.Upload, Buffer.Download, Texture.Upload, and Texture.Download complete the transfer before returning.

Label GPU Work

Use BeginDebugEvent, EndDebugEvent, and InsertDebugMarker to identify recorded GPU work in diagnostics.