dijkstra.h

/*
 * Copyright 2022 Adobe. All rights reserved.
 * This file is licensed to you under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License. You may obtain a copy
 * of the License at http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under
 * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
 * OF ANY KIND, either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
#pragma once
 
#ifdef LAGRANGE_ENABLE_LEGACY_FUNCTIONS
    #include <lagrange/legacy/internal/dijkstra.h>
#endif
 
#include <lagrange/SurfaceMesh.h>
#include <lagrange/utils/function_ref.h>
#include <lagrange/utils/span.h>
 
#include <Eigen/Core>
 
#include <queue>
#include <vector>
 
namespace lagrange::internal {

template <typename Scalar, typename Index>
struct DijkstraCache
{
    using Entry = std::pair<Scalar, Index>;
    std::priority_queue<Entry, std::vector<Entry>, std::greater<Entry>> queue;
    std::vector<bool> visited;
    std::vector<bool> visited_edges;
    std::vector<bool> chord_bridged;
    std::vector<Index> edge_indices;
};

template <typename Scalar>
struct DijkstraOptions
{
    Scalar geodesic_radius = 0;

    Scalar euclidean_radius = 0;

    Eigen::Vector3<Scalar> seed_position = Eigen::Vector3<Scalar>::Zero();
};

template <typename Scalar, typename Index>
void dijkstra(
    SurfaceMesh<Scalar, Index>& mesh,
    span<const Index> seed_vertices,
    span<const Scalar> seed_vertex_dist,
    const DijkstraOptions<Scalar>& dijkstra_options,
    const function_ref<Scalar(Index, Index)>& dist,
    const function_ref<void(Index, Scalar)>& process,
    DijkstraCache<Scalar, Index>* cache = nullptr);
 
} // namespace lagrange::internal