If a single-colour sprite it too light in my game I want to apply a drop shadow to it. The intensity should depend on the average RGB lightness.
Option 1: Use a bitmap dropshadow and control the intensity with alpha. This is not ideal, because I have to create a drop shadow bitmap for every object that needs it.
Option 2: SHADERS! Surely this must be possible using a shader? They are still a mystery to me, so I wouldn't know where to start.
Option 3: Maybe there is a better way still?