diff options
Diffstat (limited to 'game/terrain2.cpp')
| -rw-r--r-- | game/terrain2.cpp | 33 |
1 files changed, 32 insertions, 1 deletions
diff --git a/game/terrain2.cpp b/game/terrain2.cpp index 83df3fa..cc0bf90 100644 --- a/game/terrain2.cpp +++ b/game/terrain2.cpp @@ -48,6 +48,32 @@ TerrainMesh::TerrainMesh(const std::filesystem::path & input) update_vertex_normals(); }; +OpenMesh::FaceHandle +TerrainMesh::findPoint(glm::vec2 p) const +{ + return findPoint(p, *faces_begin()); +} + +OpenMesh::FaceHandle +TerrainMesh::findPoint(glm::vec2 p, OpenMesh::FaceHandle f) const +{ + ConstFaceVertexIter vertices; + while (f.is_valid() && !triangleContainsPoint(p, vertices = cfv_iter(f))) { + for (auto next = cfh_iter(f); next.is_valid(); ++next) { + f = opposite_face_handle(*next); + if (f.is_valid()) { + const auto e1 = point(to_vertex_handle(*next)); + const auto e2 = point(to_vertex_handle(opposite_halfedge_handle(*next))); + if ((e2.x - e1.x) * (p.y - e1.y) > (e2.y - e1.y) * (p.x - e1.x)) { + break; + } + } + f.reset(); + } + } + return f; +} + bool TerrainMesh::triangleContainsPoint(const glm::vec2 p, const glm::vec2 a, const glm::vec2 b, const glm::vec2 c) { @@ -61,6 +87,11 @@ TerrainMesh::triangleContainsPoint(const glm::vec2 p, const glm::vec2 a, const g bool TerrainMesh::triangleContainsPoint(const glm::vec2 p, FaceHandle face) const { - auto vertices = cfv_iter(face); + return triangleContainsPoint(p, cfv_iter(face)); +} + +bool +TerrainMesh::triangleContainsPoint(const glm::vec2 p, ConstFaceVertexIter vertices) const +{ return triangleContainsPoint(p, point(*vertices++), point(*vertices++), point(*vertices++)); } |