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Index › Programming Questions & Help › Programs › background brush
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background brush (Read 1085 times)
Nastasia
background brush
Apr 22nd, 2009, 2:10pm  
I need to make a brush which draws on top of an image which changes when c is pressed on the keyboard. The brush is erased because of the image as a background.  Embarrassed Can someone please help? I know i need to organize it into arrays and loops but can someone help with code.
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PhiLho 
Re: background brush
Reply #1 - Apr 23rd, 2009, 1:50am  
You want to change the background while preserving the previous strokes?
A way to do that is to paint on a PImage (PGraphics actually): in Java2D mode, background is transparent, so you can paint that image on top of the background: even if you change it, the painting is still there.
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hackdan
Re: background brush!
Reply #2 - May 29th, 2009, 2:19pm  
hi maybe you try this!:

PGraphics pg;

void setup(){
 size(400, 400);  
 background(255);
 pg = createGraphics(400, 400, P2D);
}

void draw() {
   background(imageBg);
   if(i<255)
     i++;
   if(i>=255)
     i = 0;
    if(mousePressed){
       pg.beginDraw();
       pg.stroke(255,34,58);
       pg.line(pmouseX, pmouseY, mouseX, mouseY);
       pg.endDraw();
    }
    image(pg,0,0);
}

good luck
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