Method pointInPolygon

App/interaction/picking/PickingSystem.cpp:190–207

// Ray casting алгоритм для point-in-polygon
template <typename T> bool PickingSystem::pointInPolygon(const T& point, std::span<T> polygon) {
    bool inside = false;
    const int x = static_cast<int>(point.x);
    const int y = static_cast<int>(point.y);
    const size_t n = polygon.size();

    for (size_t i = 0, j = n - 1; i < n; j = i++) {
        const int xi = static_cast<int>(polygon[i].x), yi = static_cast<int>(polygon[i].y);
        const int xj = static_cast<int>(polygon[j].x), yj = static_cast<int>(polygon[j].y);

        const bool intersects = ((yi > y) != (yj > y)) && (x < (xj - xi) * (y - yi) / (yj - yi) + xi);
        if (intersects) {
            inside = !inside;
        }
    }

    return inside;
}

template <typename T> bool PickingSystem::pointInRect(const T& point, const T& start, const T& end) {
    int minX = std::min(static_cast<int>(start.x), static_cast<int>(end.x));