I’m trying to create a draw with pencil and eraser. I really want to make use of setting the context in Render2D.globalcompositeoperation = ‘destination-out’ in order to create an erasing the line behavior. How would I go about doing that? Any hints towards the proper direction would be much appreciated.
I don’t know if that property is meant to be accessed through Processing, but have you checked out blendMode()?
In fact, I think blendMode() was implemented through
globalCompositeOperation, looking at this Github issue
Maybe @lmccart can speak more to this?
Edit: Okay, I realize I didn’t actually answer the question.
If we want a simple, MSPaint eraser, we could draw an ellipse, filled with the background-color, wherever the mouse is.
If we wanted to get fancy, we could store the ‘pencil marks’ in a PGraphic, and draw an ellipse filled with a color with
0 alpha onto the PGraphic using blendMode(REPLACE).