Merge branch 'main' of https://github.com/jdolan/ObjectivelyGPU

Author: jdolan

Sources/ObjectivelyGPU/Buffer.c

@@ -28,6 +28,7 @@
 #include "CommandBuffer.h"
 #include "CopyPass.h"
 #include "RenderDevice.h"
+#include "TransferBuffer.h"
 
 #define _Class _Buffer
 
@@ -129,30 +130,19 @@ static void upload(Buffer *self, const void *data, Uint32 size, Uint32 offset, b
   assert(data);
   assert(size);
 
-  SDL_GPUTransferBuffer *tbuf = SDL_CreateGPUTransferBuffer(self->device->device, &(SDL_GPUTransferBufferCreateInfo) {
-    .usage = SDL_GPU_TRANSFERBUFFERUSAGE_UPLOAD,
-    .size = size,
-  });
-  GPU_Assert(tbuf, "SDL_CreateGPUTransferBuffer");
-
-  void *mapped = SDL_MapGPUTransferBuffer(self->device->device, tbuf, cycle);
-  GPU_Assert(mapped, "SDL_MapGPUTransferBuffer");
-
-  memcpy(mapped, data, size);
-  SDL_UnmapGPUTransferBuffer(self->device->device, tbuf);
+  const TransferBuffer *tbuf = $(self->device, stageData, data, size);
 
   CommandBuffer *commands = $(self->device, acquireCommandBuffer);
   CopyPass *copyPass = $(commands, beginCopyPass);
 
   $(copyPass, uploadBuffer,
-    &(SDL_GPUTransferBufferLocation) { .transfer_buffer = tbuf },
+    &(SDL_GPUTransferBufferLocation) { .transfer_buffer = tbuf->buffer },
     &(SDL_GPUBufferRegion) { .buffer = self->buffer, .offset = offset, .size = size },
     cycle);
 
   release(copyPass);
   $(commands, submit);
   release(commands);
-  SDL_ReleaseGPUTransferBuffer(self->device->device, tbuf);
 }
 
 #pragma mark - Class lifecycle

Sources/ObjectivelyGPU/CopyPass.c

@@ -28,6 +28,7 @@
 #include "CopyPass.h"
 #include "QueryPool.h"
 #include "RenderDevice.h"
+#include "TransferBuffer.h"
 
 #define _Class _CopyPass
 
@@ -147,24 +148,12 @@ static void uploadData(const CopyPass *self, SDL_GPUBuffer *dst, const void *dat
   assert(data);
   assert(size);
 
-  SDL_GPUTransferBuffer *tbuf = SDL_CreateGPUTransferBuffer(self->commands->device->device, &(SDL_GPUTransferBufferCreateInfo) {
-    .usage = SDL_GPU_TRANSFERBUFFERUSAGE_UPLOAD,
-    .size = size,
-  });
-  GPU_Assert(tbuf, "SDL_CreateGPUTransferBuffer");
-
-  void *mapped = SDL_MapGPUTransferBuffer(self->commands->device->device, tbuf, cycle);
-  GPU_Assert(mapped, "SDL_MapGPUTransferBuffer");
-
-  memcpy(mapped, data, size);
-  SDL_UnmapGPUTransferBuffer(self->commands->device->device, tbuf);
+  const TransferBuffer *tbuf = $(self->commands->device, stageData, data, size);
 
   SDL_UploadToGPUBuffer(self->pass,
-    &(SDL_GPUTransferBufferLocation) { .transfer_buffer = tbuf },
+    &(SDL_GPUTransferBufferLocation) { .transfer_buffer = tbuf->buffer },
     &(SDL_GPUBufferRegion) { .buffer = dst, .offset = offset, .size = size },
     cycle);
-
-  SDL_ReleaseGPUTransferBuffer(self->commands->device->device, tbuf);
 }
 
 /**

Sources/ObjectivelyGPU/RenderDevice.c

@@ -118,6 +118,7 @@ static void dealloc(Object *self) {
 
   RenderDevice *this = (RenderDevice *) self;
 
+  release(this->scratch);
   release(this->framebuffer);
 
   if (this->window && this->device) {
@@ -610,6 +611,30 @@ static void setWindow(RenderDevice *self, SDL_Window *window) {
   }
 }
 
+/**
+ * @fn TransferBuffer *RenderDevice::stageData(RenderDevice *self, const void *data, Uint32 size)
+ * @memberof RenderDevice
+ */
+static TransferBuffer *stageData(RenderDevice *self, const void *data, Uint32 size) {
+
+  assert(data);
+  assert(size);
+
+  if (self->scratch == NULL || self->scratch->size < size) {
+    release(self->scratch);
+    self->scratch = $(self, createTransferBuffer, &(SDL_GPUTransferBufferCreateInfo) {
+      .usage = SDL_GPU_TRANSFERBUFFERUSAGE_UPLOAD,
+      .size = size,
+    });
+  }
+
+  void *mapped = $(self->scratch, map, true);
+  memcpy(mapped, data, size);
+  $(self->scratch, unmap);
+
+  return self->scratch;
+}
+
 /**
  * @fn bool RenderDevice::supportsPresentMode(const RenderDevice *self, SDL_GPUPresentMode mode)
  * @memberof RenderDevice
@@ -701,6 +726,7 @@ static void initialize(Class *clazz) {
   ((RenderDeviceInterface *) clazz->interface)->setFramebuffer = setFramebuffer;
   ((RenderDeviceInterface *) clazz->interface)->setSwapchainParameters = setSwapchainParameters;
   ((RenderDeviceInterface *) clazz->interface)->setWindow = setWindow;
+  ((RenderDeviceInterface *) clazz->interface)->stageData = stageData;
   ((RenderDeviceInterface *) clazz->interface)->supportsPresentMode = supportsPresentMode;
   ((RenderDeviceInterface *) clazz->interface)->supportsSwapchainComposition = supportsSwapchainComposition;
   ((RenderDeviceInterface *) clazz->interface)->textureSupportsFormat = textureSupportsFormat;

Sources/ObjectivelyGPU/RenderDevice.h

@@ -117,7 +117,14 @@ struct RenderDevice {
    * @private
    */
   SwapchainTexture swapchain;
-  
+
+  /**
+   * @brief The scratch upload transfer buffer shared by streaming uploads
+   *   (`stageData`), created and grown on demand and cycled thereafter.
+   * @private
+   */
+  TransferBuffer *scratch;
+
   /**
    * @brief User data.
    */
@@ -559,6 +566,21 @@ struct RenderDeviceInterface {
    */
   void (*setWindow)(RenderDevice *self, SDL_Window *window);
 
+  /**
+   * @fn TransferBuffer *RenderDevice::stageData(RenderDevice *self, const void *data, Uint32 size)
+   * @brief Stages `size` bytes of `data` into this device's shared scratch
+   *   upload transfer buffer, which is created or grown on demand and mapped
+   *   with cycling thereafter -- back-to-back uploads neither stall on frames
+   *   in flight nor create and release a transfer buffer per call.
+   * @param self The RenderDevice.
+   * @param data The data to stage.
+   * @param size The size of `data`, in bytes.
+   * @return The scratch transfer buffer, ready to source an upload. Borrowed,
+   *   not retained; its contents are valid only until the next `stageData`.
+   * @memberof RenderDevice
+   */
+  TransferBuffer *(*stageData)(RenderDevice *self, const void *data, Uint32 size);
+
   /**
    * @fn bool RenderDevice::supportsPresentMode(const RenderDevice *self, SDL_GPUPresentMode mode)
    * @brief Queries whether this device's swapchain supports the given present mode.