| src | Source texture. |
| dst | Destination texture. |
| 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.
When you copy from an element it does not perform any scaling. As a result, the source and destination sizes must be the same. Texture formats should be compatible, for example, TextureFormat.ARGB32
and RenderTextureFormat.ARGB32. MSAA sample counts for render textures should also be the same. Generally, you can always copy formats that are exactly the same, but format compatibility does vary
between graphics APIs. On some platforms (e.g. D3D11) you can also copy between formats that are of the same bit width.
You can load Textures at different resolutions by using QualitySettings.masterTextureLimit. Note that this affects CopyTextures as you cannot copy a full mip between textures with different master
texture limit values. If you need to copy between textures with a different master texture limit, use the region-based overload. The region-based overload adjusts the source rectangle based on the source
texture's master texture limit. It also adjusts the destination offset based on the destination's master texture limit. For example, copying a 128x128 area from position 16,16 to position 32,32 results
in the following behaviours in these example cases:
Mipmap level arguments always apply to the texture as loaded under the current master texture limit. For example, a 256x256 texture with master texture limit set to 0 mip 1 refers to a 128x128 mip.
However, if the mastertexture limit is set to 2 on that texture, mip 1 refers to a 32x32 mip. This means that in many cases when using CopyTexture you do not need to take the master texture limit into
account in your calls. In less common calls (for example, copying from Texture2D to TextureArray) you do need to adjust for it. To copy textures in a cubemap array, calculate the destination element as
6 * cubemapIndex + faceIndex. As a result, the six faces from the cubemap at index 0 are elements 0,1,2... 5. The six faces from the cubemap at array index 1 are 6,7 .... 11 and so on.
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, BCn, 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.