Respecting alpha
Posted: Sat Jun 24, 2017 6:47 pm
I can't find a way to apply certain simple effects to a png with transparency. If I do, the effect gets applied to the whole background.
Take this image to test with :
If I take two copies and try to invert one I get this:
If I then try to lighten the other I get this:
It is not all effects but Invert, Contrast and Hue Saturation affect the background or just treat the alpha as black. Incidentally, Invert, Contrast and Colour FFGL effects seem to respect the alpha more in line with expectations but now that I'm trying to go completely 64bit FFGL is not (currently) an option.
Take this image to test with :
- A white square surrounded by a black square where the centre and the outside are transparent
- invert_test.png (2.18 KiB) Viewed 5003 times
- Left copy is Inverted
- invert_test_result_01.png (3.54 KiB) Viewed 5003 times
- The right copy has HueSaturation with Lightness applied
- invert_test_result_02.png (3.5 KiB) Viewed 5003 times
