|srcElement||Source texture element (cubemap face, texture array layer or 3D texture depth slice).|
|srcMip||Source texture mipmap level.|
|dstElement||Destination texture element (cubemap face, texture array layer or 3D texture depth slice).|
|dstMip||Destination texture mipmap level.|
|srcX||X coordinate of source texture region to copy (left side is zero).|
|srcY||Y coordinate of source texture region to copy (bottom is zero).|
|srcWidth||Width of source texture region to copy.|
|srcHeight||Height of source texture region to copy.|
|dstX||X coordinate of where to copy region in destination texture (left side is zero).|
|dstY||Y coordinate of where to copy region in destination texture (bottom is zero).|
Copy texture contents.
This function allows copying pixel data from one texture into another efficiently.
It also allows copying from an element (e.g. cubemap face) or a specific mip level, and from a subregion of a texture.
Copying does not do any scaling, i.e. source and destination sizes must be the same. Texture formats should be compatible (for example, TextureFormat.ARGB32 and RenderTextureFormat.ARGB32 are compatible). Exact rules for which formats are compatible vary a bit between graphics APIs; generally formats that are exactly the same can always be copied. On some platforms (e.g. D3D11) you can also copy between formats that are of the same bit width.
Compressed texture formats add some restrictions to the CopyTexture with a region variant. For example, PVRTC formats are not supported since they are not block-based (for these formats you can only copy whole texture or whole mip level). For block-based formats (e.g. DXT, ETC), the region size and coordinates must be a multiple of compression block size (4 pixels for DXT).
If both source and destination textures are marked as "readable" (i.e. copy of data exists in system memory for reading/writing on the CPU), these functions copy it as well.
Some platforms might not have functionality of all sorts of texture copying (e.g. copy from a render texture into a regular texture). See CopyTextureSupport, and use SystemInfo.copyTextureSupport to check.
Calling Texture2D.Apply, Texture2DArray.Apply or Texture3D.Apply after
CopyTexture yields undefined results as
CopyTexture operates on GPU-side data exclusively, whereas
Apply transfers data from CPU to GPU-side.
See Also: CopyTextureSupport.