Changing one color on the fly?

[Raoul]

Hi,
is there any function in GML which allows to replace one color from the palette used in the game with another one?

I have a background picture, which uses only 4 colors. What I am trying to achieve is to change any of the 4 colors on the fly, like if I had modified the original picture but done in memory only.

Any idea?

 

[FlameRooster]

There is no function to change the colors on a palette. You would have to code it yourself or use an extension.

PixelatedPope's retro palette swapper extension can do what you are looking for.

I think it only works with pixel art though.

 

[Focksbot]

One way you could do it is to separate your background sprite out four different sprites, one for each of your four colours. Change each one to a mixture of white and transparency, draw them on top of one another, and then colour each one of them with image_blend.

Now you'll be able to change the colour of each sprite independently, and they'll all come together to create your original image.

 

[Raoul]

Hey guys, thanks to both for your quick answers, this community rocks!

@FlameRooster: I thought so but it was worth asking. Long time ago, (almost 20 years sigh) I used to code in a now dead language which had such function, Div Games Studio was the development environment.
My background is pixel art (a classic arcade remake), but I would refrain from using anyone's else libraries as I love to write everything by myself.

@Focksbot: Your suggestion should work, I will do some paint.net work and test it!