alpha channel
The
alpha channel of an image (a
masked texture) determines which parts of the image are
transparent and how
transparent they are when displayed. The
TGA file format supports an
alpha channel;
BMP and
JPEG do not (though
JPEG2000, which
SecondLife uses internally, does), and
GIFs (which can't be uploaded directly into
SecondLife anyway) support
binary transparency (meaning that a given pixel can only be either fully transparent or fully
opaque).
texture |
opacity/transparency |
alpha
