From 617875531acd375e77f142fdb04fd219162c1237 Mon Sep 17 00:00:00 2001
From: Jack Andersen <jackoalan@gmail.com>
Date: Tue, 2 Apr 2019 18:30:18 -1000
Subject: [PATCH] Implement CAABox::getTri

---
 include/zeus/CAABox.hpp | 15 ++++++++++++-
 src/CAABox.cpp          | 49 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 63 insertions(+), 1 deletion(-)

diff --git a/include/zeus/CAABox.hpp b/include/zeus/CAABox.hpp
index 8dba2c8..bf71d11 100644
--- a/include/zeus/CAABox.hpp
+++ b/include/zeus/CAABox.hpp
@@ -18,7 +18,14 @@ class CAABox {
 public:
   enum class EBoxEdgeId { Z0, X0, Z1, X1, Z2, X2, Z3, X3, Y0, Y1, Y2, Y3 };
 
-  enum class EBoxFaceID {};
+  enum class EBoxFaceId {
+    YMin,
+    YMax,
+    XMin,
+    XMax,
+    ZMax,
+    ZMin
+  };
 
   CVector3f min;
   CVector3f max;
@@ -128,6 +135,12 @@ public:
     }
   }
 
+  struct Tri {
+    zeus::CPlane x0_plane;
+    zeus::CVector3f x10_[3];
+  };
+  Tri getTri(EBoxFaceId face, int windOffset) const;
+
   CAABox getTransformedAABox(const CTransform& xfrm) const {
     CAABox box;
     CVector3f point = xfrm * getPoint(0);
diff --git a/src/CAABox.cpp b/src/CAABox.cpp
index d100bda..2793222 100644
--- a/src/CAABox.cpp
+++ b/src/CAABox.cpp
@@ -110,4 +110,53 @@ CAABox CAABox::booleanIntersection(const CAABox& other) const {
   return {minVec, maxVec};
 }
 
+CAABox::Tri CAABox::getTri(EBoxFaceId face, int windOffset) const {
+  zeus::CVector3f verts[] = {
+    {min.x(), min.y(), max.z()},
+    min,
+    {max.x(), min.y(), min.z()},
+    {max.x(), min.y(), max.z()}};
+  switch (face) {
+  case EBoxFaceId::YMin:
+  default:
+    verts[0].assign(min.x(), min.y(), max.z());
+    verts[1].assign(max.x(), min.y(), max.z());
+    verts[2].assign(max.x(), min.y(), min.z());
+    verts[3] = min;
+    break;
+  case EBoxFaceId::YMax:
+    verts[0] = max;
+    verts[1].assign(min.x(), max.y(), max.z());
+    verts[2].assign(min.x(), max.y(), min.z());
+    verts[3].assign(max.x(), max.y(), min.z());
+    break;
+  case EBoxFaceId::XMin:
+    verts[0].assign(min.x(), max.y(), max.z());
+    verts[1].assign(min.x(), min.y(), max.z());
+    verts[2] = min;
+    verts[3].assign(min.x(), max.y(), min.z());
+    break;
+  case EBoxFaceId::XMax:
+    verts[0].assign(max.x(), min.y(), max.z());
+    verts[1] = max;
+    verts[2].assign(max.x(), max.y(), min.z());
+    verts[3].assign(max.x(), min.y(), min.z());
+    break;
+  case EBoxFaceId::ZMax:
+    verts[0].assign(min.x(), max.y(), max.z());
+    verts[1] = max;
+    verts[2].assign(max.x(), min.y(), max.z());
+    verts[3].assign(min.x(), min.y(), max.z());
+    break;
+  case EBoxFaceId::ZMin:
+    verts[0] = min;
+    verts[1].assign(max.x(), min.y(), min.z());
+    verts[2].assign(max.x(), max.y(), min.z());
+    verts[3].assign(min.x(), max.y(), min.z());
+    break;
+  }
+  return {zeus::CPlane(verts[windOffset % 2], verts[(windOffset + 1) % 2], verts[(windOffset + 2) % 2]),
+          verts[windOffset % 2], verts[(windOffset + 1) % 2], verts[(windOffset + 2) % 2]};
+}
+
 } // namespace zeus