from __future__ import annotations import math from dataclasses import dataclass @dataclass(frozen=True) class Box: x_min: float y_min: float x_max: float y_max: float @property def width(self) -> float: return max(0.0, self.x_max - self.x_min) @property def height(self) -> float: return max(0.0, self.y_max - self.y_min) @property def area(self) -> float: return self.width * self.height def intersection(self, other: "Box") -> "Box | None": x_min = max(self.x_min, other.x_min) y_min = max(self.y_min, other.y_min) x_max = min(self.x_max, other.x_max) y_max = min(self.y_max, other.y_max) if x_max <= x_min or y_max <= y_min: return None return Box(x_min=x_min, y_min=y_min, x_max=x_max, y_max=y_max) def contains_point(self, x: float, y: float) -> bool: return self.x_min <= x <= self.x_max and self.y_min <= y <= self.y_max def to_polygon(self) -> tuple[tuple[float, float], ...]: return ( (self.x_min, self.y_min), (self.x_max, self.y_min), (self.x_max, self.y_max), (self.x_min, self.y_max), ) def to_list(self) -> list[float]: return [self.x_min, self.y_min, self.x_max, self.y_max] def signed_polygon_area(points: list[tuple[float, float]] | tuple[tuple[float, float], ...]) -> float: if len(points) < 3: return 0.0 area = 0.0 for index, point in enumerate(points): next_point = points[(index + 1) % len(points)] area += point[0] * next_point[1] - next_point[0] * point[1] return area / 2.0 def polygon_area(points: list[tuple[float, float]] | tuple[tuple[float, float], ...]) -> float: return abs(signed_polygon_area(points)) def polygon_bounds(points: list[tuple[float, float]] | tuple[tuple[float, float], ...]) -> Box: return Box( x_min=min(point[0] for point in points), y_min=min(point[1] for point in points), x_max=max(point[0] for point in points), y_max=max(point[1] for point in points), ) def rotated_rectangle_points( x: float, y: float, width: float, height: float, rotation_degrees: float, ) -> tuple[tuple[float, float], ...]: rotation_radians = math.radians(rotation_degrees) cos_theta = math.cos(rotation_radians) sin_theta = math.sin(rotation_radians) return ( (x, y), (x + width * cos_theta, y + width * sin_theta), (x + width * cos_theta - height * sin_theta, y + width * sin_theta + height * cos_theta), (x - height * sin_theta, y + height * cos_theta), ) def point_in_convex_polygon( point: tuple[float, float], polygon: tuple[tuple[float, float], ...], ) -> bool: if len(polygon) < 3: return False orientation = 1 if signed_polygon_area(polygon) >= 0 else -1 point_x, point_y = point for index, start in enumerate(polygon): end = polygon[(index + 1) % len(polygon)] cross = ((end[0] - start[0]) * (point_y - start[1])) - ( (end[1] - start[1]) * (point_x - start[0]) ) if orientation * cross < -1e-9: return False return True def line_intersection( line1_start: tuple[float, float], line1_end: tuple[float, float], line2_start: tuple[float, float], line2_end: tuple[float, float], ) -> tuple[float, float]: x1, y1 = line1_start x2, y2 = line1_end x3, y3 = line2_start x4, y4 = line2_end denominator = ((x1 - x2) * (y3 - y4)) - ((y1 - y2) * (x3 - x4)) if abs(denominator) < 1e-12: return line1_end determinant1 = (x1 * y2) - (y1 * x2) determinant2 = (x3 * y4) - (y3 * x4) x = ((determinant1 * (x3 - x4)) - ((x1 - x2) * determinant2)) / denominator y = ((determinant1 * (y3 - y4)) - ((y1 - y2) * determinant2)) / denominator return (x, y) def polygon_intersection( subject_polygon: tuple[tuple[float, float], ...] | list[tuple[float, float]], clip_polygon: tuple[tuple[float, float], ...], ) -> list[tuple[float, float]]: output = list(subject_polygon) if len(output) < 3 or len(clip_polygon) < 3: return [] orientation = 1 if signed_polygon_area(clip_polygon) >= 0 else -1 def is_inside(point: tuple[float, float], edge_start: tuple[float, float], edge_end: tuple[float, float]) -> bool: cross = ((edge_end[0] - edge_start[0]) * (point[1] - edge_start[1])) - ( (edge_end[1] - edge_start[1]) * (point[0] - edge_start[0]) ) return orientation * cross >= -1e-9 for index, clip_start in enumerate(clip_polygon): clip_end = clip_polygon[(index + 1) % len(clip_polygon)] input_points = output output = [] if not input_points: break previous_point = input_points[-1] for current_point in input_points: current_inside = is_inside(current_point, clip_start, clip_end) previous_inside = is_inside(previous_point, clip_start, clip_end) if current_inside: if not previous_inside: output.append( line_intersection(previous_point, current_point, clip_start, clip_end) ) output.append(current_point) elif previous_inside: output.append( line_intersection(previous_point, current_point, clip_start, clip_end) ) previous_point = current_point return output