I recently pushed a patch which inverses the meaning of the alpha channel almost everywhere in Clonk, both for engine and script. Previously, alpha=0 meant the color to be opaque, and for alpha=255 it was transparent. This has been inversed, so that alpha=0 is transparent and alpha=255 is opaque.

As far as scripting is concerned, the following needs to be payed attention to:

• I changed the RGB function so that it continues to produce an opaque color.


• However, if you are using RGBa, you most likely want to change its alpha value to 255 minus itself, to keep getting the same effect.


• To reset an object's ClrModulation, SetClrModulation(0) no longer works; this renders the object invisible now. Use SetClrModulation() or SetClrModulation(RGB(255,255,255)) instead.


• Likewise, for an unmodulated object, GetClrModulation() no longer returns 0, but RGB(255,255,255).

I made this change because

• this is how the alpha channel is used almost everywhere else.


• OGRE material scripts use this convention, and it becomes hard or even impossible to covert them to Clonk's old convention for more advanced scripts (which are not yet supported, but might well be in the future).

A few spots might have been missed during the conversion, so if, after having taken care of the points above, an object does not behave as you expect it to with respect to its transparency, feel free to assume it is an engine bug, and tell us.