Can there exist multiple pairs of beginDraw() and endDraw() invoked on the same PGraphics in the same frame?

Processing Beginners
2

Can there exist multiple pairs of beginDraw() and endDraw() invoked on the same PGraphics in the same frame?

Yes

Example code that worked with P2D:

Code 
PGraphics a;
PGraphics b;

char c;

void setup()
  {
  size(600, 200, P2D);
  a = createGraphics(180, 180, P2D);
  b = createGraphics(180, 180, P2D);
  
  a.beginDraw();
  //a.background(255, 0, 0); // Set initial background
  a.textAlign(CENTER, CENTER);
  a.textSize(96);
  c = 'A';
  a.endDraw();
  
  b.beginDraw();
  //b.background(0, 255, 0); // Set initial background
  b.endDraw();
  
  imageMode(CENTER);
  
  noLoop();
  }
  
void draw()
  {
  // Set background and paint over
  a.beginDraw();
  a.background(155, 128, 0); // Set background to pain over
  //a.clear();
  a.text(c, a.width/3, a.height/2);
  a.endDraw();
  
  image(a, width/6, height/2); 
  
  c++;
  // Adds to above
  a.beginDraw();
  a.text(c, 2*a.width/3, a.width/2);
  a.endDraw();
  
  c++;
  if(c>'A' + 25) c = 'A';
  
  image(a, 3*width/6, height/2);  
  
  // Display image
  b.beginDraw();
  b.image(a, 0, 0);
  b.endDraw();
  
  image(b, 5*width/6, height/2);
  
  noLoop();
  }

void keyPressed()
  {
  loop();
  }

I had initial issues without P2D and worked directly with P2D.

Advance frames with a key press.

References:

:)

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