From 16985b0e9bf0611301f30bd17c8c343ef1209d9a Mon Sep 17 00:00:00 2001
From: Jack Andersen <jackoalan@gmail.com>
Date: Sun, 17 Sep 2017 17:02:19 -1000
Subject: [PATCH] Add CPlane::rayPlaneIntersection

---
 include/zeus/CPlane.hpp |  4 +++-
 src/CPlane.cpp          | 17 +++++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/include/zeus/CPlane.hpp b/include/zeus/CPlane.hpp
index 3fcc8fa..4797ea2 100644
--- a/include/zeus/CPlane.hpp
+++ b/include/zeus/CPlane.hpp
@@ -48,11 +48,13 @@ public:
         d = nd * mag;
     }
 
-    float pointToPlaneDist(const zeus::CVector3f& pos) const
+    float pointToPlaneDist(const CVector3f& pos) const
     {
         return pos.dot(vec) - d;
     }
 
+    bool rayPlaneIntersection(const CVector3f& from, const CVector3f& to, CVector3f& point) const;
+
     const CVector3f& normal() const { return vec; }
 
     inline float& operator[](size_t idx) { return p[idx]; }
diff --git a/src/CPlane.cpp b/src/CPlane.cpp
index 8f3628f..e508295 100644
--- a/src/CPlane.cpp
+++ b/src/CPlane.cpp
@@ -1 +1,18 @@
 #include "zeus/CPlane.hpp"
+
+namespace zeus
+{
+
+bool CPlane::rayPlaneIntersection(const CVector3f& from, const CVector3f& to, CVector3f& point) const
+{
+    zeus::CVector3f delta = to - from;
+    if (std::fabs(delta.normalized().dot(vec)) < 0.01f)
+        return false;
+    float tmp = -pointToPlaneDist(from) / delta.dot(vec);
+    if (tmp < -0.f || tmp > 1.0001f)
+        return false;
+    point = delta * tmp + from;
+    return true;
+}
+
+}