//create offscreen graphics buffers
PGraphics context1;
PGraphics context2;

void setup()
{
  size(300,300,P3D);
  
  //initialize our offscreen graphics buffers
  context1 = createGraphics(width-20,height-20, P3D);
  context2 = createGraphics(width-20,height-20, P3D);
}

void draw()
{
  background(mouseY,0,0);
  lights();
  
  pushMatrix();
  translate(58, 48, 20);
  rotateY(0.5);
  fill(200,0,200);
  stroke(200,0,200);
  box(40);
  popMatrix();
  
  if(mousePressed)
  {
    //only draw our contexts if we need them..
    context1Draw();
    context2Draw();
    noTint();
    image(context1,10,10);
    tint(0,0,0,mouseX);
    image(context2,10,10); 
  } 
}

void context1Draw()
{
  context1.beginDraw();
  context1.background(200);
  context1.lights();
  context1.fill(200,200,0);
  context1.stroke(200,200,0);
  context1.translate(58, 48, 0);
  context1.rotateY(0.5);
  context1.box(40);
  context1.endDraw();  
}

void context2Draw()
{
  context2.beginDraw();
  context2.background(100);
  context2.lights();
  context2.fill(0,0,200);
  context2.stroke(0,0,200);
  context2.translate(58, 48, 0);
  context2.rotateY(-0.5);
  context2.sphere(40);
  context2.endDraw();
}

 

PGraphics context1;
 
void setup()
{
  size(300,300,P3D);
  context1 = createGraphics(width-20,height-20, P3D);
}
 
void draw()
{
/*  background(mouseY,0,0);*/
  stroke(0,255,0);
  line(0,0,width,height);
  context1.beginDraw();
  context1.background(0,0,0);
  context1.fill(0,0,255);
  context1.stroke(200,0,0);
  context1.translate(60, 60, 0);
  context1.box(40);
  image(context1,0,0);
}