---
title: "copy(from:sourceSlice:sourceLevel:sourceOrigin:sourceSize:to:destinationOffset:destinationBytesPerRow:destinationBytesPerImage:)"
framework: metal
role: symbol
role_heading: Instance Method
path: "metal/mtlblitcommandencoder/copy(from:sourceslice:sourcelevel:sourceorigin:sourcesize:to:destinationoffset:destinationbytesperrow:destinationbytesperimage:)"
---

# copy(from:sourceSlice:sourceLevel:sourceOrigin:sourceSize:to:destinationOffset:destinationBytesPerRow:destinationBytesPerImage:)

Encodes a command that copies image data from a texture slice to a buffer.

## Declaration

```swift
func copy(from sourceTexture: any MTLTexture, sourceSlice: Int, sourceLevel: Int, sourceOrigin: MTLOrigin, sourceSize: MTLSize, to destinationBuffer: any MTLBuffer, destinationOffset: Int, destinationBytesPerRow: Int, destinationBytesPerImage: Int)
```

## Parameters

- `sourceTexture`: A texture with an doc://com.apple.metal/documentation/Metal/MTLTexture/isFramebufferOnly property value of doc://com.apple.documentation/documentation/Swift/false that the command copies data from.
- `sourceSlice`: A slice within sourceTexture. For textures that use a combined depth/stencil pixel format, call the doc://com.apple.metal/documentation/Metal/MTLBlitCommandEncoder/copy(from:sourceSlice:sourceLevel:sourceOrigin:sourceSize:to:destinationOffset:destinationBytesPerRow:destinationBytesPerImage:options:) method instead. Configure that method’s options parameter appropriately.
- `sourceLevel`: A mipmap level within sourceTexture.
- `sourceOrigin`: A location within sourceTexture that the command begins copying data from. Assign 0 to each dimension that’s not relevant to sourceTexture. For example: If the source texture is a 2D texture, set the origin’s doc://com.apple.metal/documentation/Metal/MTLOrigin/z property to 0. If the source texture is a 1D texture, set the origin’s doc://com.apple.metal/documentation/Metal/MTLOrigin/y and doc://com.apple.metal/documentation/Metal/MTLOrigin/z properties to 0.
- `sourceSize`: An doc://com.apple.metal/documentation/Metal/MTLSize instance, which can represent a 3D region, that instructs the command how many pixels to copy from sourceTexture, starting at sourceOrigin. Assign 1 to each dimension that’s not relevant to sourceTexture. For example: If the source texture is a 2D texture, set the size’s doc://com.apple.metal/documentation/Metal/MTLSize/depth property to 1. If the source texture is a 1D texture, set the size’s doc://com.apple.metal/documentation/Metal/MTLSize/height and doc://com.apple.metal/documentation/Metal/MTLSize/depth properties to 1. If sourceTexture uses a compressed pixel format, set sourceSize to a multiple of the pixel format’s block size. If the block extends outside the bounds of the texture, clamp sourceSize to the edge of the texture.
- `destinationBuffer`: A buffer the command copies data to.
- `destinationOffset`: A byte offset within destinationBuffer the command copies to, which needs to be a multiple of the source texture’s pixel size, in bytes.
- `destinationBytesPerRow`: The number of bytes between adjacent rows of pixels in the destination buffer’s memory, which needs to be: A multiple of the source texture’s pixel size, in bytes Less than or equal to the product of the source texture’s pixel size, in bytes, and the largest pixel width the source texture’s type allows If sourceTexture uses a compressed pixel format, set destinationBytesPerRow to the number of bytes between the starts of two row blocks.
- `destinationBytesPerImage`: The number of bytes between each 2D image of a 3D texture. This value needs to be a multiple of the source texture’s pixel size, in bytes. Set this value to 0 for 2D textures, which means sourceSize.doc://com.apple.metal/documentation/Metal/MTLSize/depth is equal to 1.

## Mentioned in

Copying data to a private resource

## Discussion

Discussion This method is the equivalent of passing an empty OptionSet to the options parameter of copy(from:sourceSlice:sourceLevel:sourceOrigin:sourceSize:to:destinationOffset:destinationBytesPerRow:destinationBytesPerImage:options:). In Swift, pass [] to represent an empty option set, and in Objective-C, pass MTLBlitOptionNone. important: If the pixel format of sourceTexture is a PVRTC format, use copy(from:sourceSlice:sourceLevel:sourceOrigin:sourceSize:to:destinationOffset:destinationBytesPerRow:destinationBytesPerImage:options:) instead.

## See Also

### Copying texture data to a buffer

- [copy(from:sourceSlice:sourceLevel:sourceOrigin:sourceSize:to:destinationOffset:destinationBytesPerRow:destinationBytesPerImage:options:)](metal/mtlblitcommandencoder/copy(from:sourceslice:sourcelevel:sourceorigin:sourcesize:to:destinationoffset:destinationbytesperrow:destinationbytesperimage:options:).md)