Adding Blend Mode strange artifacts

Question

Here is the code I use for my add blend method:

public int add(int a, int b) {
    return min(a + b, 255);
}

public int min(int a, int b) {
    return (a < b) ? a : b;
}

Now if I loop through my two pixel arrays like this:

for (int i = 0; i < Game.WIDTH * Game.HEIGHT; i++) {
    Game.pixels[i] = add(Game.pixels[i], lighting.pixels[i]);
}

The result is supposed to look like this (reproduced on paint.NET):

Instead, it looks like this:

My question is: Why are there oval shaped artefacts where the colours blend and how can I fix this? Additionally, I cannot replicate multiply blend mode either, potentially for the same reason...

Answer 1

Actually, adding two integers straight from an array is not how to do it. Instead you need to split the number up in to it's separate RGB, and then add them up individually, then compile them back into a single number.

(Yeah I found out how to in the end. Just in case someone has similar problem)