cu2quPen
- class fontTools.pens.cu2quPen.Cu2QuMultiPen(other_pens, max_err, reverse_direction=False)[source]
A filter multi-pen to convert cubic bezier curves to quadratic b-splines in a interpolation-compatible manner, using the FontTools SegmentPen protocol.
- Parameters
other_pens – list of SegmentPens used to draw the transformed outlines.
max_err – maximum approximation error in font units. For optimal results, if you know the UPEM of the font, we recommend setting this to a value equal, or close to UPEM / 1000.
reverse_direction – flip the contours’ direction but keep starting point.
This pen does not follow the normal SegmentPen protocol. Instead, its moveTo/lineTo/qCurveTo/curveTo methods take a list of tuples that are arguments that would normally be passed to a SegmentPen, one item for each of the pens in other_pens.
- class fontTools.pens.cu2quPen.Cu2QuPen(other_pen, max_err, reverse_direction=False, stats=None, ignore_single_points=False)[source]
A filter pen to convert cubic bezier curves to quadratic b-splines using the FontTools SegmentPen protocol.
- Parameters
other_pen – another SegmentPen used to draw the transformed outline.
max_err – maximum approximation error in font units. For optimal results, if you know the UPEM of the font, we recommend setting this to a value equal, or close to UPEM / 1000.
reverse_direction – flip the contours’ direction but keep starting point.
stats – a dictionary counting the point numbers of quadratic segments.
ignore_single_points – don’t emit contours containing only a single point
NOTE: The “ignore_single_points” argument is deprecated since v1.3.0, which dropped Robofab support. It’s no longer needed to special-case UFO2-style anchors (aka “named points”) when using ufoLib >= 2.0, as these are no longer drawn onto pens as single-point contours, but are handled separately as anchors.
- addComponent(glyphName, transformation)[source]
Add a sub glyph. The ‘transformation’ argument must be a 6-tuple containing an affine transformation, or a Transform object from the fontTools.misc.transform module. More precisely: it should be a sequence containing 6 numbers.
- closePath()[source]
Close the current sub path. You must call either pen.closePath() or pen.endPath() after each sub path.
- curveTo(*points)[source]
Draw a cubic bezier with an arbitrary number of control points.
The last point specified is on-curve, all others are off-curve (control) points. If the number of control points is > 2, the segment is split into multiple bezier segments. This works like this:
Let n be the number of control points (which is the number of arguments to this call minus 1). If n==2, a plain vanilla cubic bezier is drawn. If n==1, we fall back to a quadratic segment and if n==0 we draw a straight line. It gets interesting when n>2: n-1 PostScript-style cubic segments will be drawn as if it were one curve. See decomposeSuperBezierSegment().
The conversion algorithm used for n>2 is inspired by NURB splines, and is conceptually equivalent to the TrueType “implied points” principle. See also decomposeQuadraticSegment().
- endPath()[source]
End the current sub path, but don’t close it. You must call either pen.closePath() or pen.endPath() after each sub path.
- moveTo(pt)[source]
Begin a new sub path, set the current point to ‘pt’. You must end each sub path with a call to pen.closePath() or pen.endPath().
- qCurveTo(*points)[source]
Draw a whole string of quadratic curve segments.
The last point specified is on-curve, all others are off-curve points.
This method implements TrueType-style curves, breaking up curves using ‘implied points’: between each two consequtive off-curve points, there is one implied point exactly in the middle between them. See also decomposeQuadraticSegment().
The last argument (normally the on-curve point) may be None. This is to support contours that have NO on-curve points (a rarely seen feature of TrueType outlines).
- class fontTools.pens.cu2quPen.Cu2QuPointPen(other_point_pen, max_err, reverse_direction=False, stats=None)[source]
A filter pen to convert cubic bezier curves to quadratic b-splines using the RoboFab PointPen protocol.
- Parameters
other_point_pen – another PointPen used to draw the transformed outline.
max_err – maximum approximation error in font units. For optimal results, if you know the UPEM of the font, we recommend setting this to a value equal, or close to UPEM / 1000.
reverse_direction – reverse the winding direction of all contours.
stats – a dictionary counting the point numbers of quadratic segments.
- addPoint(pt, segmentType=None, smooth=False, name=None, identifier=None, **kwargs)
Add a point to the current sub path.
- beginPath(identifier=None, **kwargs)
Start a new sub path.
- endPath()
End the current sub path.