Use this to compress textures generated at runtime. Compressed textures use less
graphics memory and are faster to render.
After compression, texture will be in DXT1 format if the original texture had no alpha channel, and in DXT5 format if it had alpha channel.
highQuality parameter will dither the source texture during compression,
which helps to reduce compression artifacts but is slightly slower.
If the graphics card does not support compression or the texture is already in compressed format, then Compress will do nothing.
In the Editor scripts, you probably want to use EditorUtility.CompressTexture, which will compress using slower, but higher quality DXT compression. It can also compress into non-DXT compressed formats.
See Also: SetPixels, EditorUtility.CompressTexture, LoadRawTextureData.