Repo created

libs/routing/joint_index.cpp

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+#include "routing/joint_index.hpp"
+
+#include "routing/routing_exceptions.hpp"
+
+namespace routing
+{
+void JointIndex::Build(RoadIndex const & roadIndex, uint32_t numJoints)
+{
+  // + 1 is protection for 'End' method from out of bounds.
+  // Call End(numJoints-1) requires more size, so add one more item.
+  // Therefore m_offsets.size() == numJoints + 1,
+  // And m_offsets.back() == m_points.size()
+  m_offsets.assign(numJoints + 1, 0);
+
+  // Calculate sizes.
+  // Example for numJoints = 6:
+  // 2, 5, 3, 4, 2, 3, 0
+  roadIndex.ForEachRoad([this, numJoints](uint32_t /* featureId */, RoadJointIds const & road)
+  {
+    road.ForEachJoint([this, numJoints](uint32_t /* pointId */, Joint::Id jointId)
+    {
+      UNUSED_VALUE(numJoints);
+      ASSERT_LESS(jointId, numJoints, ());
+      ++m_offsets[jointId];
+    });
+  });
+
+  // Fill offsets with end bounds.
+  // Example: 2, 7, 10, 14, 16, 19, 19
+  for (size_t i = 1; i < m_offsets.size(); ++i)
+    m_offsets[i] += m_offsets[i - 1];
+
+  m_points.resize(m_offsets.back());
+
+  // Now fill points.
+  // Offsets after this operation are begin bounds:
+  // 0, 2, 7, 10, 14, 16, 19
+  roadIndex.ForEachRoad([this](uint32_t featureId, RoadJointIds const & road)
+  {
+    road.ForEachJoint([this, featureId](uint32_t pointId, Joint::Id jointId)
+    {
+      uint32_t & offset = m_offsets[jointId];
+      --offset;
+      m_points[offset] = {featureId, pointId};
+    });
+  });
+
+  CHECK_EQUAL(m_offsets[0], 0, ());
+  CHECK_EQUAL(m_offsets.back(), m_points.size(), ());
+}
+}  // namespace routing