@@ -549,10 +549,40 @@ func (rce RenderCommandEncoder) DrawPrimitives(typ PrimitiveType, vertexStart, v
// Reference: https://developer.apple.com/documentation/metal/mtlblitcommandencoder.
type BlitCommandEncoder struct {
	CommandEncoder
}

// CopyFromTexture encodes a command to copy image data from a slice of
// a source texture into a slice of a destination texture.
//
// Reference: https://developer.apple.com/documentation/metal/mtlblitcommandencoder/1400754-copyfromtexture.
func (bce BlitCommandEncoder) CopyFromTexture(
	src Texture, srcSlice, srcLevel int, srcOrigin Origin, srcSize Size,
	dst Texture, dstSlice, dstLevel int, dstOrigin Origin,
) {
	C.BlitCommandEncoder_CopyFromTexture(
		bce.commandEncoder,
		src.texture, C.uint_t(srcSlice), C.uint_t(srcLevel),
		C.struct_Origin{
			X: C.uint_t(srcOrigin.X),
			Y: C.uint_t(srcOrigin.Y),
			Z: C.uint_t(srcOrigin.Z),
		},
		C.struct_Size{
			Width:  C.uint_t(srcSize.Width),
			Height: C.uint_t(srcSize.Height),
			Depth:  C.uint_t(srcSize.Depth),
		},
		dst.texture, C.uint_t(dstSlice), C.uint_t(dstLevel),
		C.struct_Origin{
			X: C.uint_t(dstOrigin.X),
			Y: C.uint_t(dstOrigin.Y),
			Z: C.uint_t(dstOrigin.Z),
		},
	)
}

// Synchronize flushes any copy of the specified resource from its corresponding
// Device caches and, if needed, invalidates any CPU caches.
//
// Reference: https://developer.apple.com/documentation/metal/mtlblitcommandencoder/1400775-synchronize.
func (bce BlitCommandEncoder) Synchronize(resource Resource) {
@@ -600,10 +630,29 @@ func NewTexture(texture unsafe.Pointer) Texture {
}

// resource implements the Resource interface.
func (t Texture) resource() unsafe.Pointer { return t.texture }

// ReplaceRegion copies a block of pixels into a section of texture slice 0.
//
// Reference: https://developer.apple.com/documentation/metal/mtltexture/1515464-replaceregion.
func (t Texture) ReplaceRegion(region Region, level int, pixelBytes *byte, bytesPerRow uintptr) {
	r := C.struct_Region{
		Origin: C.struct_Origin{
			X: C.uint_t(region.Origin.X),
			Y: C.uint_t(region.Origin.Y),
			Z: C.uint_t(region.Origin.Z),
		},
		Size: C.struct_Size{
			Width:  C.uint_t(region.Size.Width),
			Height: C.uint_t(region.Size.Height),
			Depth:  C.uint_t(region.Size.Depth),
		},
	}
	C.Texture_ReplaceRegion(t.texture, r, C.uint_t(level), unsafe.Pointer(pixelBytes), C.size_t(bytesPerRow))
}

// GetBytes copies a block of pixels from the storage allocation of texture
// slice zero into system memory at a specified address.
//
// Reference: https://developer.apple.com/documentation/metal/mtltexture/1515751-getbytes.
func (t Texture) GetBytes(pixelBytes *byte, bytesPerRow uintptr, region Region, level int) {

@@ -97,10 +97,14 @@ void CommandEncoder_EndEncoding(void * commandEncoder);
void RenderCommandEncoder_SetRenderPipelineState(void * renderCommandEncoder, void * renderPipelineState);
void RenderCommandEncoder_SetVertexBuffer(void * renderCommandEncoder, void * buffer, uint_t offset, uint_t index);
void RenderCommandEncoder_SetVertexBytes(void * renderCommandEncoder, const void * bytes, size_t length, uint_t index);
void RenderCommandEncoder_DrawPrimitives(void * renderCommandEncoder, uint8_t primitiveType, uint_t vertexStart, uint_t vertexCount);

void BlitCommandEncoder_CopyFromTexture(void * blitCommandEncoder,
	void * srcTexture, uint_t srcSlice, uint_t srcLevel, struct Origin srcOrigin, struct Size srcSize,
	void * dstTexture, uint_t dstSlice, uint_t dstLevel, struct Origin dstOrigin);
void BlitCommandEncoder_Synchronize(void * blitCommandEncoder, void * resource);

void * Library_MakeFunction(void * library, const char * name);

void Texture_ReplaceRegion(void * texture, struct Region region, uint_t level, void * pixelBytes, size_t bytesPerRow);
void Texture_GetBytes(void * texture, void * pixelBytes, size_t bytesPerRow, struct Region region, uint_t level);

@@ -154,18 +154,39 @@ void RenderCommandEncoder_DrawPrimitives(void * renderCommandEncoder, uint8_t pr
	[(id<MTLRenderCommandEncoder>)renderCommandEncoder drawPrimitives:(MTLPrimitiveType)primitiveType
	                                                      vertexStart:(NSUInteger)vertexStart
	                                                      vertexCount:(NSUInteger)vertexCount];
}

void BlitCommandEncoder_CopyFromTexture(void * blitCommandEncoder,
	void * srcTexture, uint_t srcSlice, uint_t srcLevel, struct Origin srcOrigin, struct Size srcSize,
	void * dstTexture, uint_t dstSlice, uint_t dstLevel, struct Origin dstOrigin) {
	[(id<MTLBlitCommandEncoder>)blitCommandEncoder copyFromTexture:(id<MTLTexture>)srcTexture
	                                                   sourceSlice:(NSUInteger)srcSlice
	                                                   sourceLevel:(NSUInteger)srcLevel
	                                                  sourceOrigin:(MTLOrigin){srcOrigin.X, srcOrigin.Y, srcOrigin.Z}
	                                                    sourceSize:(MTLSize){srcSize.Width, srcSize.Height, srcSize.Depth}
	                                                     toTexture:(id<MTLTexture>)dstTexture
	                                              destinationSlice:(NSUInteger)dstSlice
	                                              destinationLevel:(NSUInteger)dstLevel
	                                             destinationOrigin:(MTLOrigin){dstOrigin.X, dstOrigin.Y, dstOrigin.Z}];
}

void BlitCommandEncoder_Synchronize(void * blitCommandEncoder, void * resource) {
	[(id<MTLBlitCommandEncoder>)blitCommandEncoder synchronizeResource:(id<MTLResource>)resource];
}

void * Library_MakeFunction(void * library, const char * name) {
	return [(id<MTLLibrary>)library newFunctionWithName:[NSString stringWithUTF8String:name]];
}

void Texture_ReplaceRegion(void * texture, struct Region region, uint_t level, void * pixelBytes, size_t bytesPerRow) {
	[(id<MTLTexture>)texture replaceRegion:(MTLRegion){{region.Origin.X, region.Origin.Y, region.Origin.Z}, {region.Size.Width, region.Size.Height, region.Size.Depth}}
	                           mipmapLevel:(NSUInteger)level
	                             withBytes:(void *)pixelBytes
	                           bytesPerRow:(NSUInteger)bytesPerRow];
}

void Texture_GetBytes(void * texture, void * pixelBytes, size_t bytesPerRow, struct Region region, uint_t level) {
	[(id<MTLTexture>)texture getBytes:(void *)pixelBytes
	                      bytesPerRow:(NSUInteger)bytesPerRow
	                       fromRegion:(MTLRegion){{region.Origin.X, region.Origin.Y, region.Origin.Z}, {region.Size.Width, region.Size.Height, region.Size.Depth}}
	                      mipmapLevel:(NSUInteger)level];