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Index › Programming Questions & Help › Syntax Questions › activating and deactivating the drawing of shapes
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activating and deactivating the drawing of shapes (Read 471 times)
annemarie
activating and deactivating the drawing of shapes
Feb 13th, 2006, 5:41am  
Hi,

I am drawing a swarm of these shapes on the screen with a forloop:

     stroke(valr, valg, valb, alpha_1);
     fill(valr, valg, valb, alpha_1);
     beginShape(POLYGON);
       vertex(23, 12, -20);
       vertex(7, 16, -15);
       vertex(12, 9, -12);
       vertex(2, 3, 2);
     endShape();

     stroke(valr, valg, valb, alpha_2);
     fill(valr, valg, valb, alpha_2);
     ellipse(0, 0, 40, 40);

But I would like to (with key press - that I know how to do) to deactivate the drawing of the polygon shape in the forloop and instead draw the circles.

I realize that it is not enough to put the alpha channel down to 0 in order to 'deactivate' the polygons, because the draw function is still using power to draw the invisible polygons, while the circles are being shown ...

how do I deactivate the drawing of the polygons completely while the circles are being drawn?
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Ira
Re: activating and deactivating the drawing of sha
Reply #1 - Feb 13th, 2006, 6:43am  
top of sketch:
declare a flag ( boolean variable)
something like:  
boolean isPolySafe = true;

in draw:
if (isPolySafe){
 poly drawing code here
}
// add an else clause here if you want to draw only
// polygons OR ellipses, but not both.
stroke(valr, valg, valb, alpha_2);
fill(valr, valg, valb, alpha_2);
ellipse(0, 0, 40, 40);


in  keyPressed:
 if(value == someValue) {
  isPolySafe = false;
 } else {
   isPolySafe = true;
 }
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