Switch Eigen matrices to arrays

Author: mo-jonasganderton

src/atlas/grid/detail/grid/CubedSphere2.cc

@@ -2,7 +2,6 @@
 
 #include <cmath>
 
-#include "eckit/geometry/Sphere.h"
 #include "eckit/utils/Hash.h"
 
 namespace atlas {
@@ -115,15 +114,14 @@ PointXY CubedSphere2::ij_to_tangent_coord(idx_t i, idx_t j) const {
 
 // Transform a point on the tangent plane to a point on a cube
 PointXYZ CubedSphere2::tangent_to_xyz_coord(const PointXY& tan_coord, idx_t tile) const {
-    Vector tan_point(3);
-    Vector xyz(3);
+    PointXYZ xyz;
+    const Matrix& transform = lfric_rotations_transposed_[tile];
 
-    tan_point << tan_coord[0], tan_coord[1], 1;
+    xyz[0] = transform[0][0] * tan_coord[0] + transform[0][1] * tan_coord[1] + transform[0][2];
+    xyz[1] = transform[1][0] * tan_coord[0] + transform[1][1] * tan_coord[1] + transform[1][2];
+    xyz[2] = transform[2][0] * tan_coord[0] + transform[2][1] * tan_coord[1] + transform[2][2];
 
-    xyz = lfric_rotations_transposed_[tile] * tan_point;
-    xyz.normalize();
-
-    return {xyz(0), xyz(1), xyz(2)};
+    return PointXYZ::normalize(xyz);
 }
 
 }  // namespace grid

src/atlas/grid/detail/grid/CubedSphere2.h

@@ -4,11 +4,6 @@
 #include "atlas/runtime/Exception.h"
 #include "atlas/util/Config.h"
 #include "atlas/util/Point.h"
-#if eckit_HAVE_EIGEN
-#include "eckit/maths/Eigen.h"
-#else
-#include "eckit/maths/Matrix.h"
-#endif
 
 namespace atlas {
 namespace grid {
@@ -164,31 +159,25 @@ class CubedSphere2 : public Grid {
 private:
     std::string type_ = {"cubedsphere2"};
 
-#if eckit_HAVE_EIGEN
-    using Matrix = Eigen::Matrix3d;
-    using Vector = Eigen::Vector3d;
-#else
-    using Matrix = eckit::maths::Matrix<double>;
-    using Vector = eckit::maths::ColVector<double>;
-#endif
-
-    std::array<Matrix, 6> lfric_rotations_ = {
-        Matrix({{0, 1, 0}, {0, 0, -1}, {1, 0, 0}}),
-        Matrix({{-1, 0, 0}, {0, 0, -1}, {0, 1, 0}}),
-        Matrix({{0, -1, 0}, {0, 0, -1}, {-1, 0, 0}}),
-        Matrix({{1, 0, 0}, {0, 0, -1}, {0, -1, 0}}),
-        Matrix({{-1, 0, 0}, {0, 1, 0}, {0, 0, 1}}),
-        Matrix({{-1, 0, 0}, {0, -1, 0}, {0, 0, -1}})
-    };
-
-    std::array<Matrix, 6> lfric_rotations_transposed_ = {
-        Matrix({{0, 0, 1}, {1, 0, 0}, {0, -1, 0}}),
-        Matrix({{-1, 0, 0}, {0, 0, 1}, {0, -1, 0}}),
-        Matrix({{0, 0, -1}, {-1, 0, 0}, {0, -1, 0}}),
-        Matrix({{1, 0, 0}, {0, 0, -1}, {0, -1, 0}}),
-        Matrix({{-1, 0, 0}, {0, 1, 0}, {0, 0, 1}}),
-        Matrix({{-1, 0, 0}, {0, -1, 0}, {0, 0, -1}})
-    };
+    using Matrix = std::array<std::array<double, 3>, 3>;
+
+    std::array<Matrix, 6> lfric_rotations_ = {{
+        {{ {0, 1, 0}, {0, 0, -1}, {1, 0, 0} }},
+        {{ {-1, 0, 0}, {0, 0, -1}, {0, 1, 0} }},
+        {{ {0, -1, 0}, {0, 0, -1}, {-1, 0, 0} }},
+        {{ {1, 0, 0}, {0, 0, -1}, {0, -1, 0} }},
+        {{ {-1, 0, 0}, {0, 1, 0}, {0, 0, 1} }},
+        {{ {-1, 0, 0}, {0, -1, 0}, {0, 0, -1} }}
+    }};
+
+    std::array<Matrix, 6> lfric_rotations_transposed_ = {{
+        {{ {0, 0, 1}, {1, 0, 0}, {0, -1, 0} }},
+        {{ {-1, 0, 0}, {0, 0, 1}, {0, -1, 0} }},
+        {{ {0, 0, -1}, {-1, 0, 0}, {0, -1, 0} }},
+        {{ {1, 0, 0}, {0, 0, -1}, {0, -1, 0} }},
+        {{ {-1, 0, 0}, {0, 1, 0}, {0, 0, 1} }},
+        {{ {-1, 0, 0}, {0, -1, 0}, {0, 0, -1} }}
+    }};
 
 };