cf434fd941
git-svn-id: http://svn.robofab.com/branches/ufo3k@446 b5fa9d6c-a76f-4ffd-b3cb-f825fc41095c
125 lines
3.7 KiB
Python
125 lines
3.7 KiB
Python
|
|
__all__ = ["AbstractPointPen", "BasePointToSegmentPen" ]
|
|
|
|
class AbstractPointPen:
|
|
|
|
"""
|
|
Prototype for all PointPens. Should migrate to new style class.
|
|
"""
|
|
|
|
def beginPath(self):
|
|
"""Start a new sub path."""
|
|
raise NotImplementedError
|
|
|
|
def endPath(self):
|
|
"""End the current sub path."""
|
|
raise NotImplementedError
|
|
|
|
def addPoint(self, pt, segmentType=None, smooth=False, name=None, **kwargs):
|
|
"""Add a point to the current sub path."""
|
|
raise NotImplementedError
|
|
|
|
def addComponent(self, baseGlyphName, transformation):
|
|
"""Add a sub glyph."""
|
|
raise NotImplementedError
|
|
|
|
|
|
class BasePointToSegmentPen(AbstractPointPen):
|
|
|
|
"""Base class for retrieving the outline in a segment-oriented
|
|
way. The PointPen protocol is simple yet also a little tricky,
|
|
so when you need an outline presented as segments but you have
|
|
as points, do use this base implementation as it properly takes
|
|
care of all the edge cases.
|
|
"""
|
|
|
|
def __init__(self):
|
|
self.currentPath = None
|
|
|
|
def beginPath(self):
|
|
"""Start a new sub path."""
|
|
assert self.currentPath is None
|
|
self.currentPath = []
|
|
|
|
def _flushContour(self, segments):
|
|
"""Override this method.
|
|
|
|
It will be called for each non-empty sub path with a list
|
|
of segments: the 'segments' argument.
|
|
|
|
The segments list contains tuples of length 2:
|
|
(segmentType, points)
|
|
|
|
segmentType is one of "move", "line", "curve" or "qcurve".
|
|
"move" may only occur as the first segment, and it signifies
|
|
an OPEN path. A CLOSED path does NOT start with a "move", in
|
|
fact it will not contain a "move" at ALL.
|
|
|
|
The 'points' field in the 2-tuple is a list of point info
|
|
tuples. The list has 1 or more items, a point tuple has
|
|
four items:
|
|
(point, smooth, name, kwargs)
|
|
'point' is an (x, y) coordinate pair.
|
|
|
|
For a closed path, the initial moveTo point is defined as
|
|
the last point of the last segment.
|
|
|
|
The 'points' list of "move" and "line" segments always contains
|
|
exactly one point tuple.
|
|
"""
|
|
raise NotImplementedError
|
|
|
|
def endPath(self):
|
|
"""End the current sub path."""
|
|
assert self.currentPath is not None
|
|
points = self.currentPath
|
|
self.currentPath = None
|
|
if not points:
|
|
return
|
|
if len(points) == 1:
|
|
# Not much more we can do than output a single move segment.
|
|
pt, segmentType, smooth, name, kwargs = points[0]
|
|
segments = [("move", [(pt, smooth, name, kwargs)])]
|
|
self._flushContour(segments)
|
|
return
|
|
segments = []
|
|
if points[0][1] == "move":
|
|
# It's an open contour, insert a "move" segment for the first
|
|
# point and remove that first point from the point list.
|
|
pt, segmentType, smooth, name, kwargs = points[0]
|
|
segments.append(("move", [(pt, smooth, name, kwargs)]))
|
|
points.pop(0)
|
|
else:
|
|
# It's a closed contour. Locate the first on-curve point, and
|
|
# rotate the point list so that it _ends_ with an on-curve
|
|
# point.
|
|
firstOnCurve = None
|
|
for i in range(len(points)):
|
|
segmentType = points[i][1]
|
|
if segmentType is not None:
|
|
firstOnCurve = i
|
|
break
|
|
if firstOnCurve is None:
|
|
# Special case for quadratics: a contour with no on-curve
|
|
# points. Add a "None" point. (See also the Pen protocol's
|
|
# qCurveTo() method and fontTools.pens.basePen.py.)
|
|
points.append((None, "qcurve", None, None, None))
|
|
else:
|
|
points = points[firstOnCurve+1:] + points[:firstOnCurve+1]
|
|
|
|
currentSegment = []
|
|
for pt, segmentType, smooth, name, kwargs in points:
|
|
currentSegment.append((pt, smooth, name, kwargs))
|
|
if segmentType is None:
|
|
continue
|
|
segments.append((segmentType, currentSegment))
|
|
currentSegment = []
|
|
|
|
self._flushContour(segments)
|
|
|
|
def addPoint(self, pt, segmentType=None, smooth=False, name=None, **kwargs):
|
|
"""Add a point to the current sub path."""
|
|
self.currentPath.append((pt, segmentType, smooth, name, kwargs))
|
|
|
|
|