Rework Presentation Flow (#15)

Removes `Refresh_RenderTarget`, `Refresh_CreateRenderTarget` and `Refresh_QueueDestroyRenderTarget`. Render targets are now managed by the implementation.

Adds `REFRESH_TEXTUREFORMAT_B8G8R8A8`.

Adds `Refresh_AcquireSwapchainTexture`. Returns a swapchain texture for the requested window.

Removes `Refresh_QueuePresent`. It is now assumed that the texture returned by `Refresh_AcquireSwapchainTexture` will be presented. This texture can be manipulated like any other texture.

Adds `Refresh_GetSwapchainFormat`. Returns the swapchain format for the requested window.

Reviewed-on: #15
Co-authored-by: cosmonaut <evan@moonside.games>
Co-committed-by: cosmonaut <evan@moonside.games>

include/Refresh.h

@@ -58,7 +58,6 @@ typedef struct Refresh_Device Refresh_Device;
 typedef struct Refresh_Buffer Refresh_Buffer;
 typedef struct Refresh_Texture Refresh_Texture;
 typedef struct Refresh_Sampler Refresh_Sampler;
-typedef struct Refresh_RenderTarget Refresh_RenderTarget;
 typedef struct Refresh_ShaderModule Refresh_ShaderModule;
 typedef struct Refresh_ComputePipeline Refresh_ComputePipeline;
 typedef struct Refresh_GraphicsPipeline Refresh_GraphicsPipeline;
@@ -113,6 +112,7 @@ typedef enum Refresh_TextureFormat
 {
 	/* Color Formats */
 	REFRESH_TEXTUREFORMAT_R8G8B8A8,
+	REFRESH_TEXTUREFORMAT_B8G8R8A8,
 	REFRESH_TEXTUREFORMAT_R5G6B5,
 	REFRESH_TEXTUREFORMAT_A1R5G5B5,
 	REFRESH_TEXTUREFORMAT_B4G4R4A4,
@@ -585,7 +585,11 @@ typedef struct Refresh_GraphicsPipelineCreateInfo
 
 typedef struct Refresh_ColorAttachmentInfo
 {
-	Refresh_RenderTarget *pRenderTarget;
+	Refresh_Texture *texture; /* We can't use TextureSlice because render passes take a single rectangle. */
+	uint32_t depth;
+	uint32_t layer;
+	uint32_t level;
+	Refresh_SampleCount sampleCount;
 	Refresh_Vec4 clearColor; /* Can be ignored by RenderPass */
 	Refresh_LoadOp loadOp;
 	Refresh_StoreOp storeOp;
@@ -593,8 +597,11 @@ typedef struct Refresh_ColorAttachmentInfo
 
 typedef struct Refresh_DepthStencilAttachmentInfo
 {
-	Refresh_RenderTarget *pDepthStencilTarget;
+	Refresh_Texture *texture; /* We can't use TextureSlice because render passes take a single rectangle. */
-	Refresh_DepthStencilValue depthStencilValue; /* Can be ignored by RenderPass */
+	uint32_t depth;
+	uint32_t layer;
+	uint32_t level;
+	Refresh_DepthStencilValue depthStencilClearValue; /* Can be ignored by RenderPass */
 	Refresh_LoadOp loadOp;
 	Refresh_StoreOp storeOp;
 	Refresh_LoadOp stencilLoadOp;
@@ -831,17 +838,6 @@ REFRESHAPI Refresh_Texture* Refresh_CreateTexture(
 	Refresh_TextureCreateInfo *textureCreateInfo
 );
 
-/* Creates a color target.
- *
- * textureSlice: 		The texture slice that the color target will resolve to.
- * multisampleCount:	The MSAA value for the color target.
- */
-REFRESHAPI Refresh_RenderTarget* Refresh_CreateRenderTarget(
-	Refresh_Device *device,
-	Refresh_TextureSlice *textureSlice,
-	Refresh_SampleCount multisampleCount
-);
-
 /* Creates a buffer.
  *
  * usageFlags:	Specifies how the buffer will be used.
@@ -1053,19 +1049,6 @@ REFRESHAPI void Refresh_QueueDestroyBuffer(
 	Refresh_Buffer *buffer
 );
 
-/* Sends a color target to be destroyed by the renderer. Note that we call it
- * "QueueDestroy" because it may not be immediately destroyed by the renderer if
- * this is not called from the main thread (for example, if a garbage collector
- * deletes the resource instead of the programmer).
- *
- * renderTarget: The Refresh_ColorTarget to be destroyed.
- */
-REFRESHAPI void Refresh_QueueDestroyRenderTarget(
-	Refresh_Device *device,
-	Refresh_CommandBuffer *commandBuffer,
-	Refresh_RenderTarget *renderTarget
-);
-
 /* Sends a shader module to be destroyed by the renderer. Note that we call it
  * "QueueDestroy" because it may not be immediately destroyed by the renderer if
  * this is not called from the main thread (for example, if a garbage collector
@@ -1244,23 +1227,24 @@ REFRESHAPI Refresh_CommandBuffer* Refresh_AcquireCommandBuffer(
 	uint8_t fixed
 );
 
-/* Queues an image to be presented to a window.
+/* Acquires a texture to use for presentation.
- * The image will be presented upon the next Refresh_Submit call.
+ * May return NULL under certain conditions.
+ * If NULL, the user must ensure to not present.
+ * Once a swapchain texture is acquired,
+ * it will automatically be presented on command buffer submission.
  *
  * NOTE:
- *		It is an error to call this function in headless mode.
+ * 	It is not recommended to hold a reference to this texture long term.
- *
- * textureSlice:			The texture slice to present.
- * destinationRectangle:	The region of the window to update. Can be NULL.
- * filter:					The filter to use if scaling is required.
- * windowHandle:			The window to present to.
  */
-REFRESHAPI void Refresh_QueuePresent(
+REFRESHAPI Refresh_Texture* Refresh_AcquireSwapchainTexture(
 	Refresh_Device *device,
 	Refresh_CommandBuffer *commandBuffer,
-	Refresh_TextureSlice *textureSlice,
+	void *windowHandle
-	Refresh_Rect *destinationRectangle,
+);
-	Refresh_Filter filter,
+
+/* Returns the format of the swapchain for the given window. */
+REFRESHAPI Refresh_TextureFormat Refresh_GetSwapchainFormat(
+	Refresh_Device *device,
 	void *windowHandle
 );
 
@@ -1271,7 +1255,7 @@ REFRESHAPI void Refresh_Submit(
 	Refresh_CommandBuffer **pCommandBuffers
 );
 
-/* Waits for the previous submission to complete. */
+/* Waits for all submissions to complete. */
 REFRESHAPI void Refresh_Wait(
 	Refresh_Device *device
 );

include/Refresh_Image.h

@@ -68,17 +68,19 @@ REFRESHAPI void Refresh_Image_Free(uint8_t *mem);
 
 /* Image Write API */
 
-/* Encodes RGBA8 image data into PNG data.
+/* Encodes 32-bit color data into PNG data.
  *
  * filename:    The filename that the image will be written to.
  * w:	        The width of the PNG data.
  * h:	        The height of the PNG data.
- * data:	    The raw RGBA8 image data.
+ * bgra:		Whether the data is in BGRA8 format. Otherwise will assume RBGA8.
+ * data:	    The raw color data.
  */
 REFRESHAPI void Refresh_Image_SavePNG(
 	char const *filename,
 	int32_t w,
 	int32_t h,
+	uint8_t bgra,
 	uint8_t *data
 );
 

src/Refresh.c

@@ -305,19 +305,6 @@ Refresh_Texture* Refresh_CreateTexture(
 	);
 }
 
-Refresh_RenderTarget* Refresh_CreateRenderTarget(
-	Refresh_Device *device,
-	Refresh_TextureSlice *textureSlice,
-	Refresh_SampleCount multisampleCount
-) {
-	NULL_RETURN_NULL(device);
-	return device->CreateRenderTarget(
-		device->driverData,
-		textureSlice,
-		multisampleCount
-	);
-}
-
 Refresh_Buffer* Refresh_CreateBuffer(
 	Refresh_Device *device,
 	Refresh_BufferUsageFlags usageFlags,
@@ -557,19 +544,6 @@ void Refresh_QueueDestroyBuffer(
 	);
 }
 
-void Refresh_QueueDestroyRenderTarget(
-	Refresh_Device *device,
-	Refresh_CommandBuffer *commandBuffer,
-	Refresh_RenderTarget *renderTarget
-) {
-	NULL_RETURN(device);
-	device->QueueDestroyRenderTarget(
-		device->driverData,
-		commandBuffer,
-		renderTarget
-	);
-}
-
 void Refresh_QueueDestroyShaderModule(
 	Refresh_Device *device,
 	Refresh_CommandBuffer *commandBuffer,
@@ -738,21 +712,26 @@ Refresh_CommandBuffer* Refresh_AcquireCommandBuffer(
 	);
 }
 
-void Refresh_QueuePresent(
+Refresh_Texture* Refresh_AcquireSwapchainTexture(
 	Refresh_Device *device,
 	Refresh_CommandBuffer *commandBuffer,
-	Refresh_TextureSlice* textureSlice,
-	Refresh_Rect *destinationRectangle,
-	Refresh_Filter filter,
 	void *windowHandle
 ) {
-	NULL_RETURN(device);
+	NULL_RETURN_NULL(device);
-	device->QueuePresent(
+	return device->AcquireSwapchainTexture(
 		device->driverData,
 		commandBuffer,
-		textureSlice,
+		windowHandle
-		destinationRectangle,
+	);
-		filter,
+}
+
+Refresh_TextureFormat Refresh_GetSwapchainFormat(
+	Refresh_Device *device,
+	void *windowHandle
+) {
+	if (device == NULL) { return 0; }
+	return device->GetSwapchainFormat(
+		device->driverData,
 		windowHandle
 	);
 }

src/Refresh_Driver.h

@@ -154,6 +154,7 @@ static inline int32_t BytesPerImage(
 #define MAX_BUFFER_BINDINGS			16
 
 #define MAX_COLOR_TARGET_BINDINGS	4
+#define MAX_PRESENT_COUNT			16
 
 /* Refresh_Device Definition */
 
@@ -243,12 +244,6 @@ struct Refresh_Device
 		Refresh_TextureCreateInfo *textureCreateInfo
 	);
 
-	Refresh_RenderTarget* (*CreateRenderTarget)(
-		Refresh_Renderer *driverData,
-		Refresh_TextureSlice *textureSlice,
-		Refresh_SampleCount multisampleCount
-	);
-
 	Refresh_Buffer* (*CreateBuffer)(
 		Refresh_Renderer *driverData,
 		Refresh_BufferUsageFlags usageFlags,
@@ -367,12 +362,6 @@ struct Refresh_Device
 		Refresh_Buffer *buffer
 	);
 
-	void(*QueueDestroyRenderTarget)(
-		Refresh_Renderer *driverData,
-		Refresh_CommandBuffer *commandBuffer,
-		Refresh_RenderTarget *renderTarget
-	);
-
 	void(*QueueDestroyShaderModule)(
 		Refresh_Renderer *driverData,
 		Refresh_CommandBuffer *commandBuffer,
@@ -453,12 +442,14 @@ struct Refresh_Device
 		uint8_t fixed
 	);
 
-	void(*QueuePresent)(
+	Refresh_Texture* (*AcquireSwapchainTexture)(
 		Refresh_Renderer *driverData,
 		Refresh_CommandBuffer *commandBuffer,
-		Refresh_TextureSlice *textureSlice,
+		void *windowHandle
-		Refresh_Rect *destinationRectangle,
+	);
-		Refresh_Filter filter,
+
+	Refresh_TextureFormat (*GetSwapchainFormat)(
+		Refresh_Renderer *driverData,
 		void *windowHandle
 	);
 
@@ -490,7 +481,6 @@ struct Refresh_Device
 	ASSIGN_DRIVER_FUNC(CreateSampler, name) \
 	ASSIGN_DRIVER_FUNC(CreateShaderModule, name) \
 	ASSIGN_DRIVER_FUNC(CreateTexture, name) \
-	ASSIGN_DRIVER_FUNC(CreateRenderTarget, name) \
 	ASSIGN_DRIVER_FUNC(CreateBuffer, name) \
 	ASSIGN_DRIVER_FUNC(SetTextureData, name) \
 	ASSIGN_DRIVER_FUNC(SetTextureDataYUV, name) \
@@ -506,7 +496,6 @@ struct Refresh_Device
 	ASSIGN_DRIVER_FUNC(QueueDestroyTexture, name) \
 	ASSIGN_DRIVER_FUNC(QueueDestroySampler, name) \
 	ASSIGN_DRIVER_FUNC(QueueDestroyBuffer, name) \
-	ASSIGN_DRIVER_FUNC(QueueDestroyRenderTarget, name) \
 	ASSIGN_DRIVER_FUNC(QueueDestroyShaderModule, name) \
 	ASSIGN_DRIVER_FUNC(QueueDestroyComputePipeline, name) \
 	ASSIGN_DRIVER_FUNC(QueueDestroyGraphicsPipeline, name) \
@@ -519,7 +508,8 @@ struct Refresh_Device
 	ASSIGN_DRIVER_FUNC(BindComputeBuffers, name) \
 	ASSIGN_DRIVER_FUNC(BindComputeTextures, name) \
 	ASSIGN_DRIVER_FUNC(AcquireCommandBuffer, name) \
-	ASSIGN_DRIVER_FUNC(QueuePresent, name) \
+	ASSIGN_DRIVER_FUNC(AcquireSwapchainTexture, name) \
+	ASSIGN_DRIVER_FUNC(GetSwapchainFormat, name) \
 	ASSIGN_DRIVER_FUNC(Submit, name) \
 	ASSIGN_DRIVER_FUNC(Wait, name)
 

src/Refresh_Image.c

@@ -209,9 +209,32 @@ void Refresh_Image_SavePNG(
 	const char *filename,
 	int32_t w,
 	int32_t h,
+	uint8_t bgra,
 	uint8_t *data
 ) {
-	stbi_write_png(filename, w, h, 4, data, w * 4);
+	uint32_t i;
+	uint8_t *bgraData;
+
+	if (bgra)
+	{
+		bgraData = SDL_malloc(w * h * 4);
+
+		for (i = 0; i < w * h * 4; i += 4)
+		{
+			bgraData[i]     = data[i + 2];
+			bgraData[i + 1] = data[i + 1];
+			bgraData[i + 2] = data[i];
+			bgraData[i + 3] = data[i + 3];
+		}
+
+		stbi_write_png(filename, w, h, 4, bgraData, w * 4);
+
+		SDL_free(bgraData);
+	}
+	else
+	{
+		stbi_write_png(filename, w, h, 4, data, w * 4);
+	}
 }
 
 /* vim: set noexpandtab shiftwidth=8 tabstop=8: */