Spaces:
Running
Running
| """Calculate the area of a glyph.""" | |
| from fontTools.pens.basePen import BasePen | |
| __all__ = ["AreaPen"] | |
| class AreaPen(BasePen): | |
| def __init__(self, glyphset=None): | |
| BasePen.__init__(self, glyphset) | |
| self.value = 0 | |
| def _moveTo(self, p0): | |
| self._p0 = self._startPoint = p0 | |
| def _lineTo(self, p1): | |
| x0, y0 = self._p0 | |
| x1, y1 = p1 | |
| self.value -= (x1 - x0) * (y1 + y0) * 0.5 | |
| self._p0 = p1 | |
| def _qCurveToOne(self, p1, p2): | |
| # https://github.com/Pomax/bezierinfo/issues/44 | |
| p0 = self._p0 | |
| x0, y0 = p0[0], p0[1] | |
| x1, y1 = p1[0] - x0, p1[1] - y0 | |
| x2, y2 = p2[0] - x0, p2[1] - y0 | |
| self.value -= (x2 * y1 - x1 * y2) / 3 | |
| self._lineTo(p2) | |
| self._p0 = p2 | |
| def _curveToOne(self, p1, p2, p3): | |
| # https://github.com/Pomax/bezierinfo/issues/44 | |
| p0 = self._p0 | |
| x0, y0 = p0[0], p0[1] | |
| x1, y1 = p1[0] - x0, p1[1] - y0 | |
| x2, y2 = p2[0] - x0, p2[1] - y0 | |
| x3, y3 = p3[0] - x0, p3[1] - y0 | |
| self.value -= (x1 * (-y2 - y3) + x2 * (y1 - 2 * y3) + x3 * (y1 + 2 * y2)) * 0.15 | |
| self._lineTo(p3) | |
| self._p0 = p3 | |
| def _closePath(self): | |
| self._lineTo(self._startPoint) | |
| del self._p0, self._startPoint | |
| def _endPath(self): | |
| if self._p0 != self._startPoint: | |
| # Area is not defined for open contours. | |
| raise NotImplementedError | |
| del self._p0, self._startPoint | |