datatypes.data_fontmetrics

 1from dataclasses import dataclass, field
 2from lib import helpers
 3import drawBot
 4
 5
 6@dataclass
 7class DFontMetrics:
 8    """A dataclass for extracting and storing key font metrics from a font file using DrawBot."""
 9
10    fontPath: str
11    """File path to the font"""
12    factors: tuple[float, float] = 1, 1
13    """Scale factors for ascender and descender"""
14    ascender: int = field(init=False)
15    """The ascender height of the font, scaled by the ascender factor."""
16    cap: int = field(init=False)
17    """The cap height of the font."""
18    xheight: int = field(init=False)
19    """The x-height of the font."""
20    descender: int = field(init=False)
21    """The descender height of the font, scaled by the descender factor."""
22
23    def __post_init__(self):
24        drawBot.font(self.fontPath)
25
26        factorAsc, factorDesc = self.factors
27        self.ascender = drawBot.fontAscender() * factorAsc
28        self.cap = drawBot.fontCapHeight()
29        self.xheight = drawBot.fontXHeight()
30        self.baseline = 0
31        self.descender = drawBot.fontDescender() * factorDesc
32
33    @property
34    def values(self):
35        """
36        Returns a list of font metric values.
37
38        The returned list includes the following metrics (in order):
39
40        - ascender (excluded if within 10 units of cap height)
41        - cap height
42        - x-height
43        - baseline
44        - descender
45
46        Returns:
47            A list of font metric values with None values removed.
48        """
49
50        return helpers.removeNone(
51            [
52                (
53                    self.ascender
54                    if not helpers.isInRange(
55                        self.cap - 10, self.cap + 10, self.ascender
56                    )
57                    else None
58                ),
59                self.cap,
60                self.xheight,
61                self.baseline,
62                self.descender,
63            ]
64        )