From e8d23f3b3f4ec58d1b4d0cbde079c340f836476e Mon Sep 17 00:00:00 2001
From: William Moberg <william.moberg@live.se>
Date: Mon, 7 Dec 2015 15:59:41 +0100
Subject: [PATCH] Added AABBVsAABB function.

---
 include/Engine/Core/Collision.h |  2 ++
 src/Engine/Core/Collision.cpp   | 16 ++++++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/include/Engine/Core/Collision.h b/include/Engine/Core/Collision.h
index 67a9e808..2e90b8bf 100644
--- a/include/Engine/Core/Collision.h
+++ b/include/Engine/Core/Collision.h
@@ -11,6 +11,8 @@ bool RayAABBIntr(const Ray& ray, const AABB& box);
 bool RayVsAABB(const Ray& ray, const AABB& box);
 bool RayVsAABB(const Ray& ray, const AABB& box, float& outDistance);
 
+bool AABBVsAABB(const AABB& a, const AABB& b);
+bool AABBVsAABBTst(const AABB& a, const AABB& b);
 }
 
 #endif
\ No newline at end of file
diff --git a/src/Engine/Core/Collision.cpp b/src/Engine/Core/Collision.cpp
index fda895a4..07e37085 100644
--- a/src/Engine/Core/Collision.cpp
+++ b/src/Engine/Core/Collision.cpp
@@ -58,4 +58,20 @@ bool RayVsAABB(const Ray& ray, const AABB& box, float& outDistance)
     return true;
 }
 
+bool AABBVsAABB(const AABB& a, const AABB& b)
+{
+    const glm::vec3& aCenter = a.Center();
+    const glm::vec3& bCenter = b.Center();
+    const glm::vec3& aHSize = a.HalfSize();
+    const glm::vec3& bHSize = b.HalfSize();
+    //Test will probably exit because of the X and Z axes more often, so test them first.
+    if (abs(aCenter[0] - bCenter[0]) > (aHSize[0] + bHSize[0])) {
+        return false;
+    }
+    if (abs(aCenter[2] - bCenter[2]) > (aHSize[2] + bHSize[2])) {
+        return false;
+    }
+    return (abs(aCenter[1] - bCenter[1]) <= (aHSize[1] + bHSize[1]));
+}
+
 }
\ No newline at end of file