tituli.outlines

Glyph outlines as SVG path data — the vector form of a placed Run.

A Layout says where each run goes; this module says what it looks like as geometry: the font’s own contours, scaled to the run’s face size, advanced along the run exactly as Face.length() measures it, rotated by the run’s angle and translated to its baseline origin. The result is an SVG d string in frame pixels (y down), so a caller can draw text with no font engine at all — an animation runtime that only knows how to draw SVG, for instance (thorwhalen/an#155: *glyphs as SVG sprites, converted at compile time*).

>>> from tituli.fonts import EMBEDDED, resolve_face
>>> from tituli.layout import Run
>>> run = Run("Hi", 10.0, 50.0, resolve_face(EMBEDDED, size=40), (0, 0, 0, 255))
>>> out = run_outline(run)
>>> out.d.startswith("M")
True
>>> out.bbox.y1 <= 50.0 + 1 and out.bbox.y0 < 50.0   # ink sits on the baseline
True

Missing glyphs raise rather than drawing a box or nothing: a string the face cannot set is the caller’s decision (another face, other words), never a silent substitution.

>>> run_outline(Run("é", 0, 0, resolve_face(EMBEDDED, size=40), (0, 0, 0, 255)))
Traceback (most recent call last):
...
tituli.outlines.MissingGlyphError: 'Aileron' Regular has no glyph for 'é' (U+00E9)

Needs fontTools (pip install tituli[outlines]); imported lazily, so the rest of the package never pays for it.

Module Attributes

DFLT_PRECISION

Decimal places kept in the path data.

Functions

run_outline(run, *[, precision])

The contours of run as one SVG path, placed where the run is drawn.

Classes

Outline(d, bbox)

A run's contours as SVG path data, in frame pixels.

Exceptions

MissingGlyphError

The run's face has no glyph for one of its characters.

tituli.outlines.DFLT_PRECISION = 2

Decimal places kept in the path data. Two is a hundredth of a pixel — invisible, and it keeps the string short and byte-stable.

exception tituli.outlines.MissingGlyphError

Bases: ValueError

The run’s face has no glyph for one of its characters.

class tituli.outlines.Outline(d, bbox)

Bases: object

A run’s contours as SVG path data, in frame pixels.

bbox is the ink’s bounds (None when nothing is inked, e.g. a space).

tituli.outlines.run_outline(run, *, precision=2)

The contours of run as one SVG path, placed where the run is drawn.

Glyph i starts at face.length(text[:i]) + i * tracking along the baseline — the same advances the layout measured with, kerning included, so the outline and the layout cannot disagree about where a glyph is.

Return type:

Outline