Category: 2D Overlay
Syntax:
b2dSetTransparentIndex:Void(imageHandle:Int, index:Int)
Void
Makes one palette index draw as transparent.
Takes imageHandle (an indexed image) and index (the palette entry to treat as a hole).
Returns nothing.
The default is no transparent index at all - not index 0. Any value outside 0 to 255 turns it off again. Unless this is called, the only transparency is whatever alpha the PNG's own palette carries.
The hole is positional: the chosen index stays transparent and cycled colours flow through it, rather than the transparency travelling around with the rotation.
View detailed documentation online
b2dSetTransparentIndex(img, 0) ; index 0 becomes a hole b2dSetTransparentIndex(img, -1) ; and back to none
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