gistfile1.txt

/**
 * mask, ellipse, rects
 * Example based on: Draw a Mask example Pt.2
 * 2017-08-22 Processing 3.3.5
 https://forum.processing.org/two/discussion/23886/masking-a-shape-with-another-shape
 **/
PGraphics sourceImage1;
PGraphics maskImage1;
PGraphics sourceImage2;
PGraphics maskImage2;

size(600, 600); //size of canvas


///////////Círculo 1////////////////
sourceImage1 = createGraphics(600, 600); //size of drawing
sourceImage1.beginDraw();
sourceImage1.fill(255);
sourceImage1.rectMode(CENTER);
sourceImage1.rect(300, 180, 300, 20);
sourceImage1.rect(300, 220, 300, 20);
sourceImage1.rect(300, 260, 300, 20);
sourceImage1.rect(300, 300, 300, 20);
sourceImage1.rect(300, 340, 300, 20);
sourceImage1.rect(300, 380, 300, 20);
sourceImage1.rect(300, 420, 300, 20);
sourceImage1.endDraw();

// create mask1
maskImage1 = createGraphics(600, 600); //size of mask
maskImage1.beginDraw();
noStroke();
maskImage1.ellipse(300, 300, 250, 250);
maskImage1.endDraw();

// apply mask1 and then show mask1
sourceImage1.mask(maskImage1);
image(sourceImage1, 0, 0);//1
///////////Fin Círculo 1////////////////


///////////Círculo 2////////////////
sourceImage2 = createGraphics(600, 600); //size of drawing
sourceImage2.beginDraw();
sourceImage2.fill(255);
sourceImage2.rectMode(CENTER);
sourceImage2.rect(300, 200, 300, 20);
sourceImage2.rect(300, 240, 300, 20);
sourceImage2.rect(300, 280, 300, 20);
sourceImage2.rect(300, 320, 300, 20);
sourceImage2.rect(300, 360, 300, 20);
sourceImage2.rect(300, 400, 300, 20);
sourceImage2.endDraw();

// create mask2
maskImage2 = createGraphics(600, 600); //size of mask
maskImage2.beginDraw();
maskImage2.ellipse(300, 300, 200, 200);
maskImage2.endDraw();

// apply mask2 and then show mask2
sourceImage2.mask(maskImage2);
image(sourceImage2, 0, 0);//1
///////////Fin Círculo 1////////////////