1 files changed, 118 insertions, 0 deletions
diff --git a/game/geoDataMesh.cpp b/game/geoDataMesh.cpp
new file mode 100644
index 0000000..aaa8c9c
--- /dev/null
+++ b/game/geoDataMesh.cpp
@@ -0,0 +1,118 @@
+#include "geoDataMesh.h"
+#include <format>
+#ifndef NDEBUG
+#	include <stream_support.h>
+#endif
+
+OpenMesh::FaceHandle
+GeoDataMesh::findPoint(GlobalPosition2D coord) const
+{
+	return findPoint(coord, *faces_sbegin());
+}
+
+GeoDataMesh::PointFace::PointFace(const GlobalPosition2D coord, const GeoDataMesh * mesh) :
+	PointFace {coord, mesh, *mesh->faces_sbegin()}
+{
+}
+
+GeoDataMesh::PointFace::PointFace(const GlobalPosition2D coord, const GeoDataMesh * mesh, FaceHandle start) :
+	PointFace {coord, mesh->findPoint(coord, start)}
+{
+}
+
+OpenMesh::FaceHandle
+GeoDataMesh::PointFace::face(const GeoDataMesh * mesh, FaceHandle start) const
+{
+	if (faceCache.is_valid() && mesh->faceContainsPoint(point, faceCache)) {
+		return faceCache;
+	}
+	return (faceCache = mesh->findPoint(point, start));
+}
+
+OpenMesh::FaceHandle
+GeoDataMesh::PointFace::face(const GeoDataMesh * mesh) const
+{
+	return face(mesh, *mesh->faces_sbegin());
+}
+
+GeoDataMesh::HalfEdgeVertices
+GeoDataMesh::toVertexHandles(HalfedgeHandle halfEdge) const
+{
+	return {from_vertex_handle(halfEdge), to_vertex_handle(halfEdge)};
+}
+
+GeoDataMesh::HalfEdgePoints
+GeoDataMesh::points(HalfEdgeVertices vertices) const
+{
+	return {point(vertices.first), point(vertices.second)};
+}
+
+OpenMesh::FaceHandle
+GeoDataMesh::findPoint(const GlobalPosition2D coord, OpenMesh::FaceHandle face) const
+{
+	while (face.is_valid() && !triangle<2>(face).containsPoint(coord)) {
+		for (auto next = cfh_iter(face); next.is_valid(); ++next) {
+			face = opposite_face_handle(*next);
+			if (face.is_valid()) {
+				const auto nextPoints = points(toVertexHandles(*next));
+				if (pointLeftOfLine(coord, nextPoints.second, nextPoints.first)) {
+					break;
+				}
+			}
+			face.reset();
+		}
+	}
+	return face;
+}
+
+GlobalPosition3D
+GeoDataMesh::positionAt(const PointFace & coord) const
+{
+	return triangle<3>(coord.face(this)).positionOnPlane(coord.point);
+}
+
+bool
+GeoDataMesh::faceContainsPoint(const GlobalPosition2D coord, FaceHandle face) const
+{
+	return triangle<2>(face).containsPoint(coord);
+}
+
+OpenMesh::HalfedgeHandle
+GeoDataMesh::findBoundaryStart() const
+{
+	return *std::find_if(halfedges_sbegin(), halfedges_end(), [this](const auto heh) {
+		return is_boundary(heh);
+	});
+}
+
+[[nodiscard]] RelativePosition3D
+GeoDataMesh::difference(const HalfedgeHandle heh) const
+{
+	return ::difference(point(to_vertex_handle(heh)), point(from_vertex_handle(heh)));
+}
+
+[[nodiscard]] GlobalPosition3D
+GeoDataMesh::centre(const HalfedgeHandle heh) const
+{
+	const auto hehPoints = points(toVertexHandles(heh));
+	return midpoint(hehPoints.first, hehPoints.second);
+}
+
+void
+GeoDataMesh::sanityCheck(const std::source_location & loc) const
+{
+	if (const auto upSideDown = std::ranges::count_if(faces(), [this](const auto face) {
+			if (!triangle<2>(face).isUp()) {
+#ifndef NDEBUG
+				for (const auto vertex : fv_range(face)) {
+					CLOG(point(vertex));
+				}
+#endif
+				return true;
+			}
+			return false;
+		}) > 0) {
+		throw std::logic_error(std::format(
+				"{} upside down faces detected - checked from {}:{}", upSideDown, loc.function_name(), loc.line()));
+	}
+}