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@@ -24,16 +24,16 @@
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/**
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* # CategoryGPU
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*
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- * The GPU API offers a cross-platform way for apps to talk to modern
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- * graphics hardware. It offers both 3D graphics and "compute" support,
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- * in the style of Metal, Vulkan, and Direct3D 12.
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+ * The GPU API offers a cross-platform way for apps to talk to modern graphics
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+ * hardware. It offers both 3D graphics and "compute" support, in the style of
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+ * Metal, Vulkan, and Direct3D 12.
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*
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* A basic workflow might be something like this:
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*
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- * The app creates a GPU device with SDL_GPUCreateDevice(), and assigns it
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- * to a window with SDL_ClaimWindowForGPUDevice()--although strictly speaking
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- * you can render offscreen entirely, perhaps for image processing, and not
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- * use a window at all.
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+ * The app creates a GPU device with SDL_GPUCreateDevice(), and assigns it to
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+ * a window with SDL_ClaimWindowForGPUDevice()--although strictly speaking you
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+ * can render offscreen entirely, perhaps for image processing, and not use a
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+ * window at all.
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*
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* Next the app prepares static data (things that are created once and used
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* over and over). For example:
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@@ -48,25 +48,26 @@
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*
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* To render, the app creates one or more command buffers, with
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* SDL_AcquireGPUCommandBuffer(). Command buffers collect rendering
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- * instructions that will be submitted to the GPU in batch. Complex scenes
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- * can use multiple command buffers, maybe configured across multiple threads
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- * in parallel, as long as they are submitted in the correct order, but many
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- * apps will just need one command buffer per frame.
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+ * instructions that will be submitted to the GPU in batch. Complex scenes can
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+ * use multiple command buffers, maybe configured across multiple threads in
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+ * parallel, as long as they are submitted in the correct order, but many apps
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+ * will just need one command buffer per frame.
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*
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* Rendering can happen to a texture (what other APIs call a "render target")
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- * or it can happen to the swapchain texture (which is just a special texture that
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- * represents a window's contents). The app can use SDL_AcquireGPUSwapchainTexture()
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- * to render to the window.
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+ * or it can happen to the swapchain texture (which is just a special texture
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+ * that represents a window's contents). The app can use
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+ * SDL_AcquireGPUSwapchainTexture() to render to the window.
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*
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* Rendering actually happens in a Render Pass, which is encoded into a
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- * command buffer. One can encode multiple render passes (or alternate
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- * between render and compute passes) in a single command buffer, but many
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- * apps might simply need a single render pass in a single command buffer.
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- * Render Passes can render to up to four color textures and one depth texture simultaneously.
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- * If the set of textures being rendered to needs to change, the Render Pass must be ended and a new one must be begun.
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+ * command buffer. One can encode multiple render passes (or alternate between
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+ * render and compute passes) in a single command buffer, but many apps might
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+ * simply need a single render pass in a single command buffer. Render Passes
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+ * can render to up to four color textures and one depth texture
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+ * simultaneously. If the set of textures being rendered to needs to change,
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+ * the Render Pass must be ended and a new one must be begun.
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*
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- * The app calls SDL_BeginGPURenderPass().
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- * Then it sets states it needs for each draw:
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+ * The app calls SDL_BeginGPURenderPass(). Then it sets states it needs for
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+ * each draw:
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*
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* - SDL_BindGPUGraphicsPipeline
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* - SDL_SetGPUViewport
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@@ -82,24 +83,27 @@
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* - etc
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*
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* After all the drawing commands for a pass are complete, the app should call
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- * SDL_EndGPURenderPass(). Once a render pass ends all render-related state is reset.
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+ * SDL_EndGPURenderPass(). Once a render pass ends all render-related state is
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+ * reset.
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*
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- * The app can begin new Render Passes and make new draws in the same command buffer
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- * until the entire scene is rendered.
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+ * The app can begin new Render Passes and make new draws in the same command
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+ * buffer until the entire scene is rendered.
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*
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- * Once all of the render commands for the scene are complete,
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- * the app calls SDL_SubmitGPUCommandBuffer() to send it to the GPU for processing.
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+ * Once all of the render commands for the scene are complete, the app calls
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+ * SDL_SubmitGPUCommandBuffer() to send it to the GPU for processing.
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*
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- * If the app needs to read back data from texture or buffers, the API
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- * has an efficient way of doing this, provided that the app is willing to tolerate some latency.
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- * When the app uses SDL_DownloadFromGPUTexture() or SDL_DownloadFromGPUBuffer(), submitting the command buffer with
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- * SubmitGPUCommandBufferAndAcquireFence() will return a fence handle that the app
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- * can poll or wait on in a thread. Once the fence indicates that the command buffer is done processing,
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- * it is safe to read the downloaded data. Make sure to call SDL_ReleaseGPUFence() when done with the fence.
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+ * If the app needs to read back data from texture or buffers, the API has an
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+ * efficient way of doing this, provided that the app is willing to tolerate
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+ * some latency. When the app uses SDL_DownloadFromGPUTexture() or
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+ * SDL_DownloadFromGPUBuffer(), submitting the command buffer with
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+ * SubmitGPUCommandBufferAndAcquireFence() will return a fence handle that the
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+ * app can poll or wait on in a thread. Once the fence indicates that the
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+ * command buffer is done processing, it is safe to read the downloaded data.
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+ * Make sure to call SDL_ReleaseGPUFence() when done with the fence.
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*
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* The API also has "compute" support. The app calls SDL_GPUBeginComputePass()
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- * with compute-writeable textures and/or buffers, which can be written to in a compute shader.
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- * Then it sets states it needs for the compute dispatches:
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+ * with compute-writeable textures and/or buffers, which can be written to in
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+ * a compute shader. Then it sets states it needs for the compute dispatches:
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*
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* - SDL_BindGPUComputePipeline
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* - SDL_BindGPUComputeStorageBuffers
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@@ -111,31 +115,38 @@
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*
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* For advanced users, this opens up powerful GPU-driven workflows.
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*
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- * Graphics and compute pipelines require the use of shaders, which as mentioned above are small programs
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- * executed on the GPU. Each backend (Vulkan, Metal, D3D12) requires a different shader format.
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- * When the app creates the GPU device, the app lets the device know which shader formats the app can provide.
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- * It will then select the appropriate backend depending on the available shader formats and the backends available on the platform.
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- * When creating shaders, the app must provide the correct shader for the selected backend.
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- * If you would like to learn more about why the API works this way, there is a
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- * detailed [blog post](https://moonside.games/posts/layers-all-the-way-down/)
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+ * Graphics and compute pipelines require the use of shaders, which as
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+ * mentioned above are small programs executed on the GPU. Each backend
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+ * (Vulkan, Metal, D3D12) requires a different shader format. When the app
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+ * creates the GPU device, the app lets the device know which shader formats
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+ * the app can provide. It will then select the appropriate backend depending
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+ * on the available shader formats and the backends available on the platform.
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+ * When creating shaders, the app must provide the correct shader for the
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+ * selected backend. If you would like to learn more about why the API works
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+ * this way, there is a detailed
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+ * [blog post](https://moonside.games/posts/layers-all-the-way-down/)
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* explaining this situation.
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*
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- * It is optimal for apps to pre-compile the shader formats they might use, but for ease of use
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- * SDL provides a satellite single-header library for performing runtime shader cross-compilation:
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+ * It is optimal for apps to pre-compile the shader formats they might use,
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+ * but for ease of use SDL provides a satellite single-header library for
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+ * performing runtime shader cross-compilation:
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* https://github.com/libsdl-org/SDL_gpu_shadercross
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*
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* This is an extremely quick overview that leaves out several important
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* details. Already, though, one can see that GPU programming can be quite
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* complex! If you just need simple 2D graphics, the
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- * [Render API](https://wiki.libsdl.org/SDL3/CategoryRender) is much easier to use but still
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- * hardware-accelerated. That said, even for 2D applications the performance benefits
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- * and expressiveness of the GPU API are significant.
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- *
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- * The GPU API targets a feature set with a wide range of hardware support and ease of portability.
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- * It is designed so that the app won't have to branch itself by querying feature support.
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- * If you need cutting-edge features with limited hardware support, this API is probably not for you.
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- *
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- * Examples demonstrating proper usage of this API can be found here: https://github.com/TheSpydog/SDL_gpu_examples
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+ * [Render API](https://wiki.libsdl.org/SDL3/CategoryRender)
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+ * is much easier to use but still hardware-accelerated. That said, even for
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+ * 2D applications the performance benefits and expressiveness of the GPU API
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+ * are significant.
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+ *
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+ * The GPU API targets a feature set with a wide range of hardware support and
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+ * ease of portability. It is designed so that the app won't have to branch
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+ * itself by querying feature support. If you need cutting-edge features with
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+ * limited hardware support, this API is probably not for you.
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+ *
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+ * Examples demonstrating proper usage of this API can be found here:
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+ * https://github.com/TheSpydog/SDL_gpu_examples
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*/
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#ifndef SDL_gpu_h_
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