def drawPoints(self, pointPen): if self.drawInner: reversePen = ReverseContourPointPen(pointPen) self.innerGlyph.drawPoints(CleanPointPen(reversePen)) if self.drawOuter: self.outerGlyph.drawPoints(CleanPointPen(pointPen)) if self.drawOriginal: if self.drawOuter: pointPen = ReverseContourPointPen(pointPen) self.originalGlyph.drawPoints(CleanPointPen(pointPen)) for glyphName, transform in self.components: pointPen.addComponent(glyphName, transform)
class Cu2QuPointPen(BasePointToSegmentPen): """ A filter pen to convert cubic bezier curves to quadratic b-splines using the RoboFab PointPen protocol. other_point_pen: another PointPen used to draw the transformed outline. max_err: maximum approximation error in font units. reverse_direction: reverse the winding direction of all contours. stats: a dictionary counting the point numbers of quadratic segments. """ def __init__(self, other_point_pen, max_err, reverse_direction=False, stats=None): BasePointToSegmentPen.__init__(self) if reverse_direction: self.pen = ReverseContourPointPen(other_point_pen) else: self.pen = other_point_pen self.max_err = max_err self.stats = stats def _flushContour(self, segments): assert len(segments) >= 1 closed = segments[0][0] != "move" new_segments = [] prev_points = segments[-1][1] prev_on_curve = prev_points[-1][0] for segment_type, points in segments: if segment_type == 'curve': for sub_points in self._split_super_bezier_segments(points): on_curve, smooth, name, kwargs = sub_points[-1] bcp1, bcp2 = sub_points[0][0], sub_points[1][0] cubic = [prev_on_curve, bcp1, bcp2, on_curve] quad = curve_to_quadratic(cubic, self.max_err) if self.stats is not None: n = str(len(quad)) self.stats[n] = self.stats.get(n, 0) + 1 new_points = [(pt, False, None, {}) for pt in quad[1:-1]] new_points.append((on_curve, smooth, name, kwargs)) new_segments.append(["qcurve", new_points]) prev_on_curve = sub_points[-1][0] else: new_segments.append([segment_type, points]) prev_on_curve = points[-1][0] if closed: # the BasePointToSegmentPen.endPath method that calls _flushContour # rotates the point list of closed contours so that they end with # the first on-curve point. We restore the original starting point. new_segments = new_segments[-1:] + new_segments[:-1] self._drawPoints(new_segments) def _split_super_bezier_segments(self, points): sub_segments = [] # n is the number of control points n = len(points) - 1 if n == 2: # a simple bezier curve segment sub_segments.append(points) elif n > 2: # a "super" bezier; decompose it on_curve, smooth, name, kwargs = points[-1] num_sub_segments = n - 1 for i, sub_points in enumerate( decomposeSuperBezierSegment([pt for pt, _, _, _ in points])): new_segment = [] for point in sub_points[:-1]: new_segment.append((point, False, None, {})) if i == (num_sub_segments - 1): # the last on-curve keeps its original attributes new_segment.append((on_curve, smooth, name, kwargs)) else: # on-curves of sub-segments are always "smooth" new_segment.append((sub_points[-1], True, None, {})) sub_segments.append(new_segment) else: raise AssertionError("expected 2 control points, found: %d" % n) return sub_segments def _drawPoints(self, segments): pen = self.pen pen.beginPath() last_offcurves = [] for i, (segment_type, points) in enumerate(segments): if segment_type in ("move", "line"): assert len(points) == 1, ( "illegal line segment point count: %d" % len(points)) pt, smooth, name, kwargs = points[0] pen.addPoint(pt, segment_type, smooth, name, **kwargs) elif segment_type == "qcurve": assert len(points) >= 2, ( "illegal qcurve segment point count: %d" % len(points)) offcurves = points[:-1] if offcurves: if i == 0: # any off-curve points preceding the first on-curve # will be appended at the end of the contour last_offcurves = offcurves else: for (pt, smooth, name, kwargs) in offcurves: pen.addPoint(pt, None, smooth, name, **kwargs) pt, smooth, name, kwargs = points[-1] pen.addPoint(pt, segment_type, smooth, name, **kwargs) else: # 'curve' segments must have been converted to 'qcurve' by now raise AssertionError("unexpected segment type: %r" % segment_type) for (pt, smooth, name, kwargs) in last_offcurves: pen.addPoint(pt, None, smooth, name, **kwargs) pen.endPath() def addComponent(self, baseGlyphName, transformation): assert self.currentPath is None self.pen.addComponent(baseGlyphName, transformation)