Decorating the RF objects!

[bahman]

Hi, I wanted to add a method to the glyph object every time on startup. Like decorating the Glyph class for example I could do this:

g = CurrentGlyph()
g.myCustomMethod()
>>> "Hello!"

Is this possible?
Thanks ( ͡° ͜ʖ ͡°)

[bahman]

@frederik Yeah that is very powerful. I have another related question. let's say I want my custom method to be executed every time an object changes. I don't want to add a defcon notification but rather override a method and use the super on an internal method of glyph object, then execute my own method. I looked at defcon but it seemed that it's only possible by overriding _set_dirty, but not sure if that's the right way. What do you think?

[frederik]

If you add a method to the class all instances of the class will have that new method!

the beauty of python!

[bahman]

Ow so simple! I thought if I do that it wouldn't affect all the objects. Thank you!

[gferreira]

hello @bahman,

yes, this is possible and super useful. here’s an example:

# my custom method
def drawRect(self, x, y, w, h):
    pen = self.getPen()
    pen.moveTo((x, y))
    pen.lineTo((x + w, y))
    pen.lineTo((x + w, y + h))
    pen.lineTo((x, y + h))
    pen.closePath()

# do this once at startup
from mojo.roboFont import RGlyph
RGlyph.rect = drawRect

# then use the custom method anywhere
g = CurrentGlyph()
g.rect(0, 100, 200, 300)
g.rect(50, 400, 200, 300)

cheers!