Write color pixel to an Image

Processing Coding Questions
1

Hi, I’m trying to draw green pixel from a layer to a PImage.
But I’ve got this result unexpected :
pixelbug
The code seems ok, there is something I don’t understand.

PImage result;
PGraphics msk;
void setup() {
  size(360, 200);
  msk = createGraphics(width, height);
  result = createImage(width, height, ARGB);
  noLoop();
}
void draw() {
  msk.beginDraw();
  msk.background(0, 255);
  msk.stroke(0, 255, 0);
  msk.noFill();
  msk.strokeWeight(6);
  msk.circle(260, 60, 32);
  msk.loadPixels();
  for (int i=0; i<width; i++) {
    for (int j=0; j<height; j++) {
      if (msk.pixels[i*height+j]==#FF00FF00) {
        result.set(i, j, #FFFFFFFF);// this line is not correct
      }
    }
  }
  msk.updatePixels();
  msk.endDraw();
  image(msk, 0, 0);
  image(result, 0, 0);
}

Thanks for help !

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2

Your math for msk.pixels is off.

Try msk.pixels[ j * msk.width + i ] instead.

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