fixes fonts with Italic Angle but no Italic Slant Offset

fixItalicSlantOffset_AllLayers.py

import math

### updated version of a script by Lukas Schneider, available from the RoboFont documentation:
### http://robofont.com/documentation/tutorials/making-italic-fonts/#applying-the-italic-slant-offset-after-drawing
### changes in this version:
### - handles all layers of all open fonts
### - fixed syntax for FontParts / RoboFont 3

'''
fixes fonts with Italic Angle but no Italic Slant Offset
- calculates Italic Slant Offset based on Italic Angle and xHeight
- offsets all glyphs accordingly based on a reference glyph

'''

# ---------
# functions
# ---------

def getFlippedComponents(layer):
    flippedComponents = []
    for g in layer:
        for component in g.components:
            if component.naked().transformation:
                # flipped horizontal
                if component.naked().transformation[0] == -1:
                    flippedComponents.append(g.name)
                # flipped vertical
                if component.naked().transformation[3] == -1:
                    flippedComponents.append(g.name)
    return list(set(flippedComponents))

def offsetGlyphs(font, baseGlyph, roundOffset=False):

    for layerName in font.layerOrder:
        layer = font.getLayer(layerName)

        # calculate offset value with baseGlyph
        baseLeftMargin = (layer[baseGlyph].angledLeftMargin + layer[baseGlyph].angledRightMargin) / 2.0
        offset = -layer[baseGlyph].angledLeftMargin + baseLeftMargin

        # round offset value
        if roundOffset and offset != 0:
            offset = round(offset)

        # get flipped components
        flippedComponents = getFlippedComponents(layer)

        # apply offset to all glyphs in font
        if offset and layer[baseGlyph].angledLeftMargin and len(layer.keys()):

            # get reverse components dict
            componentMap = layer.getReverseComponentMapping()

            # apply offset to all glyphs in font
            for glyphName in layer.keys():
                layer[glyphName].prepareUndo()
                layer[glyphName].moveBy((offset, 0))
                layer[glyphName].performUndo()

                # if the glyph is used as a component, revert component offset
                for composedGlyph in componentMap.get(glyphName, []):
                    for component in layer[composedGlyph].components:
                        if component.baseGlyph == glyphName:
                            # make sure it's not a flipped component
                            if glyphName not in flippedComponents:
                                component.moveBy((-offset, 0))

                # done with glyph
                layer[glyphName].changed()

            # fix flipped components
            for glyphName in flippedComponents:
                for component in layer[glyphName].components:
                    # offset flipped components twice:
                    # baseGlyph offset + offset in the wrong direction
                    component.moveBy((offset*2, 0))

                    # fix glyphs which use the flipped component as a component
                    for composedGlyph in componentMap.get(glyphName, []):
                        for component in layer[composedGlyph].components:
                            if component.baseGlyph == glyphName:
                                component.moveBy((-offset, 0))

                # done with glyph
                layer[glyphName].changed()

# --------------
# run the script
# --------------

for font in AllFonts():

    # base glyph for offset calculation (the glyph that should be centered)
    baseGlyphName = 'H'

    # round or not the horizontal offset
    roundOffset = False

    # calculate the italic slant offset
    italicSlantOffset = math.tan(font.info.italicAngle * math.pi / 180) * (font.info.xHeight * 0.5)

    # set the italic slant offset in font
    font.lib['com.typemytype.robofont.italicSlantOffset'] = round(italicSlantOffset)

    # offset all glyphs in font
    offsetGlyphs(font, baseGlyphName, roundOffset)

on line 77 I think this sign is not supposed to be here { ?

fixed. thanks!