Check for intersection between placed blocks and entities. (#3850)

* Check for intersection between placed blocks and entities.

+ Implemented GetPlacementCollisionBox, to permit custom placement collision boxes for blocks.

* Factored block-entity placement checking into another function in cPlayer.

- Removed vector min/max functions

* Use GetWorld to get the world in DoesPlacingBlocksIntersectEntity.

+ Added block height checks, allow different cEntity subclasses to decide whether they will prevent block placement.

src/BoundingBox.cpp

@@ -60,6 +60,17 @@ cBoundingBox::cBoundingBox(const cBoundingBox & a_Orig) :
 
 
 
+cBoundingBox & cBoundingBox::operator=(const cBoundingBox & a_Other)
+{
+	m_Min = a_Other.m_Min;
+	m_Max = a_Other.m_Max;
+	return *this;
+}
+
+
+
+
+
 void cBoundingBox::Move(double a_OffX, double a_OffY, double a_OffZ)
 {
 	m_Min.x += a_OffX;
@@ -119,10 +130,10 @@ cBoundingBox cBoundingBox::Union(const cBoundingBox & a_Other)
 {
 	return cBoundingBox(
 		std::min(m_Min.x, a_Other.m_Min.x),
-		std::min(m_Min.y, a_Other.m_Min.y),
-		std::min(m_Min.z, a_Other.m_Min.z),
 		std::max(m_Max.x, a_Other.m_Max.x),
+		std::min(m_Min.y, a_Other.m_Min.y),
 		std::max(m_Max.y, a_Other.m_Max.y),
+		std::min(m_Min.z, a_Other.m_Min.z),
 		std::max(m_Max.z, a_Other.m_Max.z)
 	);
 }