Add pen which draws to TrueType glyphs.

Lib/fontTools/pens/ttGlyphPen.py

@@ -0,0 +1,80 @@
+from __future__ import print_function, division, absolute_import
+from array import array
+
+from fontTools.misc.py23 import *
+from fontTools.pens.basePen import AbstractPen
+from fontTools.ttLib.tables import ttProgram
+from fontTools.ttLib.tables._g_l_y_f import Glyph
+from fontTools.ttLib.tables._g_l_y_f import GlyphComponent
+from fontTools.ttLib.tables._g_l_y_f import GlyphCoordinates
+
+
+__all__ = ["TTGlyphPen"]
+
+
+class TTGlyphPen(AbstractPen):
+    """Pen used for drawing to a TrueType glyph."""
+
+    def __init__(self):
+        self.points = []
+        self.endPts = []
+        self.types = []
+        self.components = []
+
+    def _addPoint(self, pt, onCurve):
+        self.points.append([int(coord) for coord in pt])
+        self.types.append(onCurve)
+
+    def lineTo(self, pt):
+        self._addPoint(pt, 1)
+
+    def moveTo(self, pt):
+        assert (not self.points) or (self.endPts[-1] == len(self.points) - 1)
+        self.lineTo(pt)
+
+    def qCurveTo(self, *points):
+        for pt in points[:-1]:
+            self._addPoint(pt, 0)
+        self._addPoint(points[-1], 1)
+
+    def closePath(self):
+        endPt = len(self.points) - 1
+
+        # ignore anchors
+        if endPt == 0 or (self.endPts and endPt == self.endPts[-1] + 1):
+            self.points.pop()
+            self.types.pop()
+            return
+
+        self.endPts.append(endPt)
+
+    def endPath(self):
+        # TrueType contours are always "closed"
+        self.closePath()
+
+    def addComponent(self, glyphName, transformation):
+        component = GlyphComponent()
+        component.glyphName = glyphName
+        component.transform = (transformation[:2], transformation[2:4])
+        component.x, component.y = [int(n) for n in transformation[4:]]
+        component.flags = 0
+        self.components.append(component)
+
+    def glyph(self):
+        glyph = Glyph()
+
+        glyph.coordinates = GlyphCoordinates(self.points)
+        glyph.endPtsOfContours = self.endPts
+        glyph.flags = array("B", self.types)
+        glyph.components = self.components
+
+        # TrueType glyphs can't have both contours and components
+        if glyph.components:
+            glyph.numberOfContours = -1
+        else:
+            glyph.numberOfContours = len(glyph.endPtsOfContours)
+
+        glyph.program = ttProgram.Program()
+        glyph.program.fromBytecode("")
+
+        return glyph