implement resource containers

include/Refresh.h

@@ -1144,7 +1144,8 @@ REFRESHAPI void Refresh_DownloadFromTexture(
 	Refresh_CommandBuffer *commandBuffer,
 	Refresh_TextureSlice *textureSlice,
 	Refresh_TransferBuffer *transferBuffer,
-	Refresh_BufferImageCopy *copyParams
+	Refresh_BufferImageCopy *copyParams,
+	Refresh_TransferOptions option
 );
 
 /* Downloads data from a GpuBuffer object. */
@@ -1153,13 +1154,29 @@ REFRESHAPI void Refresh_DownloadFromBuffer(
 	Refresh_CommandBuffer *commandBuffer,
 	Refresh_GpuBuffer *gpuBuffer,
 	Refresh_TransferBuffer *transferBuffer,
-	Refresh_BufferCopy *copyParams
+	Refresh_BufferCopy *copyParams,
+	Refresh_TransferOptions option
 );
 
 /* GPU-to-GPU copies occur on the GPU timeline,
  * and you may assume the copy has finished in subsequent commands.
  */
 
+/*
+ * option:
+ *  SAFEDISCARD:
+ *    If the destination resource has been used in a copy command that has not completed,
+ *    the issued copy commands will still be valid at the cost of increased memory usage.
+ *    Otherwise the data will safely overwrite.
+ * 	  This is a good option to prevent stalls on resources with frequent updates.
+ *    It is not recommended to use this option with large resources.
+ *
+ *  SAFEOVERWRITE:
+ *    Overwrites the data regardless of whether a copy has been issued.
+ *    This will insert a memory barrier, so it could cause suboptimal performance compared to SAFEDISCARD
+ *    on resources that update frequently across submissions.
+ */
+
 /* Performs a texture-to-texture copy. */
 REFRESHAPI void Refresh_CopyTextureToTexture(
 	Refresh_Device *device,

src/Refresh.c

@@ -820,7 +820,8 @@ void Refresh_DownloadFromTexture(
 	Refresh_CommandBuffer *commandBuffer,
 	Refresh_TextureSlice *textureSlice,
 	Refresh_TransferBuffer *transferBuffer,
-	Refresh_BufferImageCopy *copyParams
+	Refresh_BufferImageCopy *copyParams,
+	Refresh_TransferOptions option
 ) {
 	NULL_RETURN(device);
 	device->DownloadFromTexture(
@@ -828,7 +829,8 @@ void Refresh_DownloadFromTexture(
 		commandBuffer,
 		textureSlice,
 		transferBuffer,
-		copyParams
+		copyParams,
+		option
 	);
 }
 
@@ -837,7 +839,8 @@ void Refresh_DownloadFromBuffer(
 	Refresh_CommandBuffer *commandBuffer,
 	Refresh_GpuBuffer *gpuBuffer,
 	Refresh_TransferBuffer *transferBuffer,
-	Refresh_BufferCopy *copyParams
+	Refresh_BufferCopy *copyParams,
+	Refresh_TransferOptions option
 ) {
 	NULL_RETURN(device);
 	device->DownloadFromBuffer(
@@ -845,7 +848,8 @@ void Refresh_DownloadFromBuffer(
 		commandBuffer,
 		gpuBuffer,
 		transferBuffer,
-		copyParams
+		copyParams,
+		option
 	);
 }
 

src/Refresh_Driver.h

@@ -460,7 +460,8 @@ struct Refresh_Device
 		Refresh_CommandBuffer *commandBuffer,
 		Refresh_TextureSlice *textureSlice,
 		Refresh_TransferBuffer *transferBuffer,
-		Refresh_BufferImageCopy *copyParams
+		Refresh_BufferImageCopy *copyParams,
+		Refresh_TransferOptions option
 	);
 
 	void (*DownloadFromBuffer)(
@@ -468,7 +469,8 @@ struct Refresh_Device
 		Refresh_CommandBuffer *commandBuffer,
 		Refresh_GpuBuffer *gpuBuffer,
 		Refresh_TransferBuffer *transferBuffer,
-		Refresh_BufferCopy *copyParams
+		Refresh_BufferCopy *copyParams,
+		Refresh_TransferOptions option
 	);
 
 	void (*CopyTextureToTexture)(