Function BuildQuadTree

src/transformations/tinshift_impl.hpp:388–424

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static std::unique_ptr<NS_PROJ::QuadTree::QuadTree<unsigned>>
BuildQuadTree(const TINShiftFile &file, bool forward) {
    auto quadtree = std::unique_ptr<NS_PROJ::QuadTree::QuadTree<unsigned>>(
        new NS_PROJ::QuadTree::QuadTree<unsigned>(GetBounds(file, forward)));
    const auto &triangles = file.triangles();
    const auto &vertices = file.vertices();
    const int idxX = file.transformHorizontalComponent() && !forward ? 2 : 0;
    const int idxY = file.transformHorizontalComponent() && !forward ? 3 : 1;
    const unsigned colCount = file.verticesColumnCount();
    for (size_t i = 0; i < triangles.size(); ++i) {
        const unsigned i1 = triangles[i].idx1;
        const unsigned i2 = triangles[i].idx2;
        const unsigned i3 = triangles[i].idx3;
        const double x1 = vertices[i1 * colCount + idxX];
        const double y1 = vertices[i1 * colCount + idxY];
        const double x2 = vertices[i2 * colCount + idxX];
        const double y2 = vertices[i2 * colCount + idxY];
        const double x3 = vertices[i3 * colCount + idxX];
        const double y3 = vertices[i3 * colCount + idxY];
        NS_PROJ::QuadTree::RectObj rect;
        rect.minx = x1;
        rect.miny = y1;
        rect.maxx = x1;
        rect.maxy = y1;
        rect.minx = std::min(rect.minx, x2);
        rect.miny = std::min(rect.miny, y2);
        rect.maxx = std::max(rect.maxx, x2);
        rect.maxy = std::max(rect.maxy, y2);
        rect.minx = std::min(rect.minx, x3);
        rect.miny = std::min(rect.miny, y3);
        rect.maxx = std::max(rect.maxx, x3);
        rect.maxy = std::max(rect.maxy, y3);
        quadtree->insert(static_cast<unsigned>(i), rect);
    }

    return quadtree;
}

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