How would I use PGraphics in a class?

lilmilkman

Hello, I'm pretty new to programming, and am working on a pretty basic drawing program. See I am trying to add undo and redo buttons. I want them to be able to affect the things I draw in the PGraphics, if that makes sense. Is there a way to fix this? Sorry if the code is excessive...

PGraphics pg;
boolean controlDown = false;
boolean shiftDown = false;
int bgColor = 255;
int pColor = 0;
int pAlpha = 255;
int selector = 0;

int pSize = 5;
int eSize = 5;

boolean drawing = false;
boolean doOnce = false;

Undo undo;

void setup() {

  size(900, 600);
  smooth();

  pg = createGraphics(width, height);

  undo = new Undo(10);
}

void draw() {

  background(bgColor);

  if(mouseX > 142) {
    noCursor();
  } else {

    cursor();
  }

  noFill();
  stroke(0);  
  if(selector == 0) {

  ellipse(mouseX, mouseY, pSize + 2, pSize + 2);
  } else {

    ellipse(mouseX, mouseY, eSize + 2, eSize + 2);
  }
}

void pencil() {

  if (mousePressed) {

    if (mouseX > 142) {

      pg.beginDraw();
      pg.stroke(pColor, pAlpha);
      pg.strokeWeight(pSize);
      pg.strokeJoin(ROUND);
      pg.line(mouseX, mouseY, pmouseX, pmouseY);
      pg.endDraw();
      image(pg, 0, 0);
    }
  }
}



void mousePressed() {

  if (mouseX > 142) {

    drawing = true;
  } else {

    drawing = false;
  }
}

void mouseReleased() {

  drawing = false;
  doOnce = false;

  if(mouseX > 142 || mouseX > 18 && mouseX < 67 && mouseY > 534 && mouseY < 586) {

  undo.takeSnapshot();
  }
}

void mouseClicked() {

  println(mouseX, mouseY);
}

void keyPressed() {

  if (key == CODED) {

    if (keyCode == CONTROL) {

      controlDown = true;
    }
    if (keyCode == SHIFT) {

      shiftDown = true;
    }

    return;
  }

  if (controlDown) {

    if (keyCode == 'Z') {

      if (shiftDown) {

        undo.redo();
      } else {

        undo.undo();
      }
    }

    return;
  }
}

void keyReleased() {

  if (key == CODED) {

    if (keyCode == CONTROL) {

      controlDown = false;
    }

    if (keyCode == SHIFT) {

      shiftDown = false;
    }
  }
}


class Undo {

  int undoSteps = 0, redoSteps = 0; 

  CircImgCollection images;

  Undo(int levels) {

    images = new CircImgCollection(levels);
  }

  public void takeSnapshot(){

    undoSteps = min(undoSteps+1, images.amount-1);
    redoSteps = 0;
    images.next();
    images.capture();
  }

  public void undo() {

    if (undoSteps > 0) {

      undoSteps--;
      redoSteps++;
      images.prev();
      images.show();
    }
  }

  public void redo() {

    if (redoSteps > 0) {

      undoSteps++;
      redoSteps--;
      images.next();
      images.show();
    }
  }
}


class CircImgCollection {

  int amount, current;  
  PImage[] img;

  CircImgCollection(int amountOfImages) {

    amount = amountOfImages;

    img = new PImage[amount];

    for (int i=0; i < amount; i++) {

      img[i] = createImage(width, height, RGB);
      img[i] = get();
    }
  }

  void next() {

    current = (current + 1) % amount;
  }

  void prev() {

    current = (current - 1 + amount) % amount;
  }

  void capture() {

    img[current] = get();
  }

  void show() {

    image(img[current], 0, 0);
  }
}

koogs

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