PVector.rotate() doesn't seem to be implemented in processing.js

thomashollier

Does anyone know how I would go about implementing this? Processing.js seems to hang whenever I use a PVector.rotate() function.

thomashollier

Actually, I see that it is implemented in the github 1.4.8 version. How do I get Processing's Javascript mode to use that version rather than the 1.4.1 it seems to currently be using?

GoToLoop

<Sketchbook Location>/modes/JavaScriptMode/template/processing.js

Some warnings though:

• I had some minor problems w/ it in my Processing 2.0.2.
• Almost all Processing host sites still use v1.4.1.
• I've failed to spot method rotate() even on v1.4.8!

At least, we can peek at Java Mode's own rotate() implementation source code:
https://github.com/processing/processing/blob/master/core/src/processing/core/PVector.java#L892

public void rotate(float theta) {
  float temp = x;
  // Might need to check for rounding errors like with angleBetween function?
  x = x*PApplet.cos(theta) - y*PApplet.sin(theta);
  y = temp*PApplet.sin(theta) + y*PApplet.cos(theta);
}

I've got an online example which uses either PVector's rotate() or a "manual" approach to it:
http://studio.processingtogether.com/sp/pad/export/ro.91nVQMnL$v06L/latest

enemy.rotate(-HALF_PI/E_SPD);
enemy.set(cos(theta -= HALF_PI/E_SPD)*rad, sin(theta)*rad, 0);

thomashollier

Thanks. I will probable go the manual way as you suggest.

nick3499

PVector rotate(float theta)

public PVector rotate(float theta) { float temp = x; // Might need to check for rounding errors like with angleBetween function? x = x*PApplet.cos(theta) - y*PApplet.sin(theta); y = temp*PApplet.sin(theta) + y*PApplet.cos(theta); return this; }