From dfea55428969e281dc3cf8f4e81894a2b17bdbce Mon Sep 17 00:00:00 2001
From: David Allemang <allemang.d@gmail.com>
Date: Sun, 28 Jun 2020 15:07:10 -0400
Subject: [PATCH] remove broken flipping mechanics

---
 vis/include/geometry.hpp | 40 ----------------------------------------
 1 file changed, 40 deletions(-)

diff --git a/vis/include/geometry.hpp b/vis/include/geometry.hpp
index b8f2546..a8a5b2a 100644
--- a/vis/include/geometry.hpp
+++ b/vis/include/geometry.hpp
@@ -28,15 +28,10 @@ struct Primitive {
 
     ~Primitive() = default;
 
-    inline void flip() {
-        if (N > 1) std::swap(inds[0], inds[1]);
-    }
-
     void apply(const tc::Cosets &table, int gen) {
         for (auto &ind : inds) {
             ind = table.get(ind, gen);
         }
-        flip();
     }
 };
 
@@ -74,28 +69,6 @@ std::vector<int> recontext_gens(
     return s_sg_gens;
 }
 
-/**
- * Determine whether the orientation of the group sg_gens is reversed from the group g_gens within group context
- */
-int get_parity(
-    const tc::Group &context,
-    const std::vector<int> &g_gens,
-    const std::vector<int> &sg_gens
-) {
-    if (g_gens.size() != sg_gens.size() + 1) return 0;
-
-    const auto proper_sg_gens = recontext_gens(context, g_gens, sg_gens);
-
-    int i = 0;
-    for (; i < sg_gens.size(); ++i) {
-        if (proper_sg_gens[i] != i) {
-            break;
-        }
-    }
-
-    return i & 1;
-}
-
 /**
  * Solve the cosets generated by sg_gens within the subgroup generated by g_gens of the group context
  */
@@ -119,16 +92,6 @@ std::vector<Primitive<N>> apply(std::vector<Primitive<N>> prims, const tc::Coset
     return prims;
 }
 
-/**
- * Reverse the orientation of all primitives in this mesh.
- */
-template<unsigned N>
-void flip(std::vector<Primitive<N>> prims) {
-    for (auto &prim : prims) {
-        prim.flip();
-    }
-}
-
 /**
  * Convert the indexes of this mesh to those of a different context, using g_gens to build the parent context and sg_gens to build this context.
  */
@@ -155,9 +118,6 @@ std::vector<Primitive<N>> recontext(
         }
     }
 
-    if (get_parity(context, g_gens, sg_gens) == 1)
-        flip(res);
-
     return res;
 }