Sidorakh
commented
1 year ago Oh yeah I'm well aware of this. There's another weird issue most likely related to this, for example, if you ste the transparent colour to c_red and draw c_blue anywhere, you'll be able to click through that blue even though that colour isn't drawn as transparent. I have no idea how to fix either of these issues though, the best I can do is just recommend you use colours with equal red and blue values
It appears that when the chroma key isn't a value with equal red and blue channels, when the background image is also that color, it continues to render that color instead of creating a cutout.
For example, a full blue chroma key and a full blue background color causes the background to still render. This all suggests that the issue with equal R and B channels is an upstream issue, as GDI expects BGR formatted colors, hinting that the issue may lie with how the GDI library is interacting with the DirectX draw calls.