| 77 | } // namespace |
| 78 | |
| 79 | void ClipTriangleByRect(m2::RectD const & rect, m2::PointD const & p1, m2::PointD const & p2, m2::PointD const & p3, |
| 80 | ClipTriangleByRectResultIt const & resultIterator) |
| 81 | { |
| 82 | if (rect.IsPointInside(p1) && rect.IsPointInside(p2) && rect.IsPointInside(p3)) |
| 83 | { |
| 84 | resultIterator(p1, p2, p3); |
| 85 | return; |
| 86 | } |
| 87 | |
| 88 | static constexpr double kEps = 1e-8; |
| 89 | std::vector<m2::PointD> polygon; |
| 90 | auto const addPolygonPoint = [&polygon](m2::PointD const & pt) |
| 91 | { |
| 92 | if (polygon.empty() || !polygon.back().EqualDxDy(pt, kEps)) |
| 93 | polygon.push_back(pt); |
| 94 | }; |
| 95 | |
| 96 | CornersT const corners = {rect.LeftTop(), rect.RightTop(), rect.RightBottom(), rect.LeftBottom()}; |
| 97 | |
| 98 | int firstClipCode[3]; |
| 99 | int lastClipCode[3]; |
| 100 | bool intersected[3]; |
| 101 | |
| 102 | intersected[0] = IntersectEdge(rect, corners, p1, p2, p3, addPolygonPoint, 0, 0, firstClipCode[0], lastClipCode[0]); |
| 103 | |
| 104 | intersected[1] = |
| 105 | IntersectEdge(rect, corners, p2, p3, p1, addPolygonPoint, lastClipCode[0], 0, firstClipCode[1], lastClipCode[1]); |
| 106 | |
| 107 | intersected[2] = IntersectEdge( |
| 108 | rect, corners, p3, p1, p2, addPolygonPoint, lastClipCode[1] != 0 ? lastClipCode[1] : lastClipCode[0], |
| 109 | firstClipCode[0] != 0 ? firstClipCode[0] : firstClipCode[1], firstClipCode[2], lastClipCode[2]); |
| 110 | |
| 111 | int const intersectCount = intersected[0] + intersected[1] + intersected[2]; |
| 112 | if (intersectCount == 0) |
| 113 | { |
| 114 | if (IsPointInsideTriangle(rect.Center(), p1, p2, p3)) |
| 115 | { |
| 116 | resultIterator(rect.LeftTop(), rect.RightTop(), rect.RightBottom()); |
| 117 | resultIterator(rect.RightBottom(), rect.LeftBottom(), rect.LeftTop()); |
| 118 | } |
| 119 | return; |
| 120 | } |
| 121 | |
| 122 | if (intersectCount == 1 && intersected[2]) |
| 123 | InsertCorners(corners, p1, p2, p3, addPolygonPoint, lastClipCode[2], firstClipCode[2]); |
| 124 | |
| 125 | if (!polygon.empty() && polygon.back().EqualDxDy(polygon[0], kEps)) |
| 126 | polygon.pop_back(); |
| 127 | |
| 128 | if (polygon.size() < 3) |
| 129 | return; |
| 130 | |
| 131 | for (size_t i = 0; i < polygon.size() - 2; ++i) |
| 132 | resultIterator(polygon[0], polygon[i + 1], polygon[i + 2]); |
| 133 | } |
| 134 | |
| 135 | template <class FnT> |
| 136 | void ClipPathByRectImpl(m2::RectD const & rect, std::vector<m2::PointD> const & path, FnT && fn) |