Set Default Broad Phase to LBVH

.gitignore

@@ -672,3 +672,4 @@ python/update_bindings.py
 tests/data
 notebooks/*.png
 CMakeGraphVizOptions.cmake
+.zed/*

docs/source/tutorials/getting_started.rst

@@ -519,7 +519,7 @@ The ``Candidates`` class represents the culled set of candidate pairs and is bui
             #include <ipc/candidates/candidates.hpp>
 
             ipc::Candidates candidates;
-            ipc::HashGrid broad_phase;
+            ipc::LBVH broad_phase;
             candidates.build(
                 mesh, vertices_t0, vertices_t1, /*inflation_radius=*/0.0, broad_phase);
 
@@ -529,9 +529,9 @@ The ``Candidates`` class represents the culled set of candidate pairs and is bui
 
             candidates = ipctk.Candidates()
             candidates.build(
-                mesh, vertices_t0, vertices_t1, broad_phase=ipctk.HashGrid())
+                mesh, vertices_t0, vertices_t1, broad_phase=ipctk.LBVH())
 
-Possible values for ``broad_phase`` are: ``BruteForce`` (parallel brute force culling), ``HashGrid`` (default), ``SpatialHash`` (implementation from the original IPC codebase), ``LBVH`` (CPU implementation of :cite:t:`Karras2012HPG` using TBB), ``SweepAndPrune`` (a.k.a. Sort-and-Sweep from :cite:t:`Baraff1992PhD`), or ``SweepAndTiniestQueue`` (method of :cite:t:`Belgrod2023Time`; requires CUDA).
+Possible values for ``broad_phase`` are: ``BruteForce`` (parallel brute force culling), ``HashGrid``, ``SpatialHash`` (implementation from the original IPC codebase), ``LBVH`` (CPU implementation of :cite:t:`Karras2012HPG` using TBB), ``SweepAndPrune`` (a.k.a. Sort-and-Sweep from :cite:t:`Baraff1992PhD`), or ``SweepAndTiniestQueue`` (method of :cite:t:`Belgrod2023Time`; requires CUDA). The default is ``LBVH``.
 
 Narrow-Phase
 ^^^^^^^^^^^^

src/ipc/broad_phase/default_broad_phase.hpp

@@ -1,14 +1,14 @@
 #pragma once
 
-#include <ipc/broad_phase/hash_grid.hpp>
+#include <ipc/broad_phase/lbvh.hpp>
 
 #include <memory>
 
 namespace ipc {
 
 inline std::unique_ptr<BroadPhase> make_default_broad_phase()
 {
-    return std::make_unique<HashGrid>();
+    return std::make_unique<LBVH>();
 }
 
 } // namespace ipc

src/ipc/broad_phase/lbvh.cpp

@@ -662,7 +662,7 @@ void LBVH::detect_candidates(
 void LBVH::detect_vertex_vertex_candidates(
     std::vector<VertexVertexCandidate>& candidates) const
 {
-    if (!has_vertices()) {
+    if (vertex_bvh.size() <= 1) { // Need at least 2 vertices for a collision
         return;
     }
 
@@ -690,7 +690,7 @@ void LBVH::detect_edge_vertex_candidates(
 void LBVH::detect_edge_edge_candidates(
     std::vector<EdgeEdgeCandidate>& candidates) const
 {
-    if (!has_edges()) {
+    if (edge_bvh.size() <= 1) { // Need at least 2 edges for a collision
         return;
     }
 
@@ -734,7 +734,7 @@ void LBVH::detect_edge_face_candidates(
 void LBVH::detect_face_face_candidates(
     std::vector<FaceFaceCandidate>& candidates) const
 {
-    if (!has_faces()) {
+    if (face_bvh.size() <= 1) { // Need at least 2 faces for a collision
         return;
     }
 

tests/src/tests/broad_phase/brute_force_comparison.cpp

@@ -89,8 +89,9 @@ void save_candidates(
 bool load_candidates(const std::string& filename, ipc::Candidates& candidates)
 {
     std::ifstream f(filename);
-    if (!f)
+    if (!f) {
         return false;
+    }
 
     nlohmann::json in;
     f >> in;

tests/src/tests/potential/test_barrier_potential.cpp

@@ -36,7 +36,6 @@ TEST_CASE(
 
     double dhat = -1;
     std::string mesh_name;
-    bool all_vertices_on_surface = true;
     SECTION("cube")
     {
         dhat = sqrt(2.0);
@@ -210,6 +209,8 @@ TEST_CASE(
             < dhat * dhat);
     }
 
+    REQUIRE(vertices.size() > 0);
+
     const CollisionMesh mesh(vertices, edges, faces);
 
     NormalCollisions collisions;