cu2quPen

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.

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 subpport. 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.

lineTo(pt)[source]

Draw a straight line from the current point to ‘pt’.

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.

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.

addComponent(baseGlyphName, transformation)[source]

Add a sub glyph.

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.