Skew only Paths and Anchors

Skew only Paths and Anchors.py

#MenuTitle: Skew only Paths and Anchors
# -*- coding: utf-8 -*-
__doc__="""
"""

import GlyphsApp
import math 

Font = Glyphs.font
Doc = Glyphs.currentDocument
selectedLayers = Font.selectedLayers

def italicSkew( x, y, angle=10.0 ):
	"""Skews x/y along the x axis and returns skewed x value."""
	new_angle = ( angle / 180.0 ) * math.pi
	return x + y * math.tan( new_angle )

# thisMasterItalicAngle = Font.masters[thisLayer.associatedMasterId].italicAngle
skewAngle = 13
skewRadians = round(math.radians(skewAngle),2)
thisMasterXHeight = Font.masters[selectedLayers[0].associatedMasterId].xHeight
italicCorrection = italicSkew( 0.0, thisMasterXHeight/2.0, skewAngle )

for thisLayer in selectedLayers:

	componentTransformDict = {}
	for thisComponent in thisLayer.components:
		componentTransformDict[thisComponent.componentName] = thisComponent.transform

	Font.disableUpdateInterface()
	thisLayer.applyTransform([
	                        1, # x scale factor
	                        0, # x skew factor
	                        skewRadians, # y skew factor
	                        1, # y scale factor
	                        -italicCorrection, # x position
	                        0  # y position
	                        ])
	
	# shift component back to original position
	for eachComponent in thisLayer.components:
		thisComponent.transform = componentTransformDict[thisComponent.componentName]
	Font.enableUpdateInterface()