Override core function

jeffthompson

Is it possible to create a function that overrides a P5 core function? I'd like to modify how some of the internal stuff works, but without compiling a separate version of the entire P5 core.

More specifically, I'd like to change how line breaks happen when the text() functions specifies a width and height, by adding additional characters that can cause a break (such as / and |).

Here's the function in question: https://github.com/processing/processing/blob/master/core/src/processing/core/PGraphics.java#L4831

Is this possible? Am I approaching this the right way?

GoToLoop

https://Forum.Processing.org/two/discussion/16314/pshape-inside-a-class-or-extend-pshape#latest

jeffthompson

Thanks GoToLoop, but I'm not sure exactly what I do with it. Would I copy the entire class into my code, and have it extend the original? Or can I just override the one function I need inside of that class?

jeremydouglass

Because PGraphics.textSentence() is protected (rather than private) you should be able to extend PGraphics and override with your own textSentence().

• https://stackoverflow.com/questions/5484031/is-it-possible-to-change-protected-variables-from-inherited-class-in-java

That said, I vaguely remember encountering frustrating limitations when working with an extended PGraphics class -- but those might have just been limitations in my understanding of Processing at the time.

GoToLoop

That was just the way I've found to both @Override & add functionality to PGraphicsJava2D.
You need to customize it to your own needs though. L-)

B/c Processing relies on createGraphics() in order to instantiate a specific PGraphics subclass, when we extend any of them, we need to write some code which would be done by createGraphics(). #:-S

kfrajer

Hmmm why would one need createGraphics instead of using a constructor? Sorry, the curiosity just bit me....

Kf

jeremydouglass

Ah, yes, that was the wrinkle! If you extend PGraphics, you also need a version of createGraphics() that will return the extended type.

A PGraphics object can be created using a constructor -- you need to use the createGraphics() function. This is described briefly in the reference ( https://processing.org/reference/PGraphics.html ) and you can find createGraphics code here -- it cascades down to makeGraphics(), which sets the renderer, parent, primary, and path.

https://github.com/processing/processing/blob/master/core/src/processing/core/PApplet.java#L2107