Preview interpolation result in the Space Center using representations.

InterpolationPreviewSpaceCenter.py

'''
just a proof of concept, name of the second master is hard-coded at the bottom

'''

from vanilla import FloatingWindow, CheckBox, Slider
from defconAppKit.windows.baseWindow import BaseWindowController
from mojo.events import addObserver, removeObserver
from mojo.UI import CurrentSpaceCenter
import mojo.drawingTools as ctx
from defcon import Glyph, registerRepresentationFactory, unregisterRepresentationFactory

def InterpolationGlyphFactory(glyph1, g2=RGlyph(), factor=0.5):
    g1 = RGlyph(glyph1)
    g3 = RGlyph()
    g3.interpolate(factor, g1, g2)
    return g3

class InterpolationPreviewSpaceCenter(BaseWindowController):

    def __init__(self, anotherFont):
        self.f2 = anotherFont
        self.w = FloatingWindow((200, 70))

        x = y = p = 10
        textHeight = 20
        self.w.factor = Slider((x, y, -p, textHeight),
                value=0.5, minValue=-0.5, maxValue=1.5,
                callback=self.updatePreviewCallback)

        y += textHeight + p
        self.w.preview = CheckBox((x, y, -p, textHeight),
                'preview', value=True,
                callback=self.updatePreviewCallback)

        self.setUpBaseWindowBehavior()
        registerRepresentationFactory(Glyph, "InterpolationPreview", InterpolationGlyphFactory)
        addObserver(self, "drawInterpolation", "spaceCenterDraw")
        self.w.open()

    def windowCloseCallback(self, sender):
        super().windowCloseCallback(sender)
        removeObserver(self, "spaceCenterDraw")
        unregisterRepresentationFactory(Glyph, "InterpolationPreview")

    def updatePreviewCallback(self, sender):
        S = CurrentSpaceCenter()
        if not S:
            return
        S.updateGlyphLineView()

    def drawInterpolation(self, notification):
        if not self.w.preview.get():
            return
        S = CurrentSpaceCenter()
        if not S:
            return

        factor = self.w.factor.get()
        g1 = notification['glyph']
        g2 = self.f2[g1.name]
        g3 = g1.getRepresentation("InterpolationPreview", g2=g2, factor=factor)
        
        ctx.fill(None)
        ctx.lineJoin('round')
        ctx.strokeWidth(2 * notification['scale'])
        ctx.stroke(1, 0, 0)
        ctx.drawGlyph(g3)


f2 = AllFonts().getFontsByStyleName('SomeOtherMaster')[0] ### style name of second master

InterpolationPreviewSpaceCenter(f2)