UITYPE AlphaMode

AlphaMode can take following values:
 * "DISABLE" - opaque texture
 * "BLEND" - normal painting on top of the background, obeying alpha channels if present in the image (uses alpha)
 * "ALPHAKEY" - one-bit alpha
 * "ADD" - additive blend
 * "MOD" - modulating blend

Examples
DISABLE: Ignores alpha channel

BLEND: Uses alpha channel

ALPHAKEY: A 1-bit alpha which interprets alpha as either transparent or opaque.

ADD: Uses alpha channel and dodges whites

MOD: Ignores alpha channel and multiplies the image.