Notes

Known issues / pitfalls

• Processing origin is always upper-left corner of window. p5.js 2D origin is upper-left corner, and 3D origin is center of screen.

• Processing resets to imageMode(CORNER) at beginning of draw(); p5.js does not.

• Classes may have multiple constructors in Java, but not Javascript. processing-p5-convert comments out all constructor declarations after the first.

• Class member variables are automatically initialized to 0 in Java but not in Javascript.

• p5.js does not permit calling API functions before initialization (e.g. sqrt). Recommendation: put all initialization in setup(), rather than in global scope.

• conversion of Processing sketches that load significant resources:
  • processing-p5-convert moves load*() calls to preload(). p5.js waits until these load calls complete before calling setup().
  • this works for conversion of .pde files to .js on the command line
  • this is inconsistent for loading/conversion of .pde files from webpage
    • sometimes works on 2nd try?
      
      
• Processing allows the user to override API functions (e.g. ellipse, hue, …). This causes problems (inconsistently) with p5.js.

TODO

• Java PApplet handling

• static methods (Java only?)

• investigate: On-demand global new p5() at top of converted code, to allow p5.js functions to be called outside setup()