29 lines
805 B
Python
29 lines
805 B
Python
from vec import Vec2
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class Path:
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def __init__(self, points: list[Vec2], extra_data: list):
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self.points: list[Vec2] = points
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self.extra_data = extra_data
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self.normals: list[Vec2] = []
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self._init_normals()
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def _init_normals(self) -> None:
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pt0 = self.points[0]
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self.normals.append(Vec2(pt0.y, -pt0.x))
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for i in range(1, len(self.points) - 1):
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pt1 = self.points[i-1]
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pt2 = self.points[i]
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pt3 = self.points[i+1]
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d1 = (pt1 - pt2).normalized()
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d2 = (pt3 - pt2).normalized()
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d = (d1 + d2).normalized()
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if d2.cross(d) < 0:
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d = -d
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self.normals.append(d)
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ptl = self.points[-1]
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self.normals.append(Vec2(ptl.y, -ptl.x)) |