Initial commit

include/icosahedron.h

@@ -0,0 +1,63 @@
+#ifndef ICOSAHEDRON_H
+#define ICOSAHEDRON_H
+#include <Eigen/Core>
+
+// Construct a triangle mesh of an icosahedron.
+//
+// Outputs:
+//   V  12 by 3 list of 3D mesh vertex positions
+//   F  20 by 3 list of triangle indices into V
+template <
+  typename DerivedV,
+  typename DerivedF
+>
+inline void icosahedron(
+  Eigen::PlainObjectBase<DerivedV> & V,
+  Eigen::PlainObjectBase<DerivedF> & F);
+
+// Implementation
+
+template <
+  typename DerivedV,
+  typename DerivedF
+>
+inline void icosahedron(
+  Eigen::PlainObjectBase<DerivedV> & V,
+  Eigen::PlainObjectBase<DerivedF> & F)
+{
+  V = (DerivedV(12,3) <<
+    0,0,1,
+    0.72360679774997894,-0.52573111211913359,0.44721359549995793,
+    0.72360679774997894,0.52573111211913359,0.44721359549995793,
+    -0.27639320225002095,0.85065080835203999,0.44721359549995793,
+    -0.89442719099991586,1.0953573965284052e-16,0.44721359549995793,
+    -0.27639320225002112,-0.85065080835203988,0.44721359549995793,
+    0.89442719099991586,0,-0.44721359549995793,
+    0.27639320225002106,0.85065080835203988,-0.44721359549995793,
+    -0.72360679774997883,0.5257311121191337,-0.44721359549995793,
+    -0.72360679774997894,-0.52573111211913348,-0.44721359549995793,
+    0.27639320225002084,-0.85065080835203999,-0.44721359549995793,
+    0,0,-1).finished();
+  F = (DerivedF(20,3)<<
+    0,1,2,
+    0,2,3,
+    0,3,4,
+    0,4,5,
+    0,5,1,
+    1,6,2,
+    2,7,3,
+    3,8,4,
+    4,9,5,
+    5,10,1,
+    6,7,2,
+    7,8,3,
+    8,9,4,
+    9,10,5,
+    10,6,1,
+    6,11,7,
+    7,11,8,
+    8,11,9,
+    9,11,10,
+    10,11,6).finished();
+}
+#endif