// Foreground Image
var fgImage = new SimpleImage( 30, 30 );

w = fgImage.getWidth();
h = fgImage.getHeight();

for ( var px of fgImage.values() ) {
    x = px.getX();
    if ( x <= h/3 || x >= h/3*2 ) {
     px.setGreen(255);   
    } else if ( x >= h/3 && x <= h/3*2 ) {
        px.setRed(255);
        px.setBlue(255);
    }
}

print(fgImage);

// Background Image
var bgImage = new SimpleImage( 30, 30 );

w = bgImage.getWidth();
h = bgImage.getHeight();

for ( var px of bgImage.values() ) {
    x = px.getX();
    if ( x <= h/3 ) {
        px.setRed(255);
        px.setGreen(255);   
    } else if ( x >= h/3 && x <= h/3*2 ) {
        px.setBlue(255);
    } else if ( x >= h/3*2 ) {
        px.setRed(255);
    }
}

print(bgImage);

// Output Image
var output = new SimpleImage( 30, 30 );

    for ( var px of fgImage.values() ) {
        x = px.getX();
        
    }

print(output);