HOW TO USE:
- create a mask sprite (opaque pixels will mask)
- add the luminosityMask effect to the mask sprite
- tweak the effect, you can see which pixel will be affected etc.
- add any blurs you want to the mask, for example the build in blur or my KawaseBlur construct.net/en/make-games/addons/1110/kawase-blur
- add the blending for example Additive or Screen
Now everything below that mask will get the bloom applied.
Imo this is the best solution for Bloom, it's really tweakable for the artist without needing to look at shader code plus it works with any blur so can be as light or heavy on performance as you want depending on your blur choice.
If you want to support me in developing more addons: ko-fi.com/fedecalchera