Updated documentation for mMaxSeparationDistance

Based on question #1379

Jolt/Physics/Collision/CollideShape.h

@@ -59,7 +59,7 @@ public:
 	Vec3						mContactPointOn1;			///< Contact point on the surface of shape 1 (in world space or relative to base offset)
 	Vec3						mContactPointOn2;			///< Contact point on the surface of shape 2 (in world space or relative to base offset). If the penetration depth is 0, this will be the same as mContactPointOn1.
 	Vec3						mPenetrationAxis;			///< Direction to move shape 2 out of collision along the shortest path (magnitude is meaningless, in world space). You can use -mPenetrationAxis.Normalized() as contact normal.
-	float						mPenetrationDepth;			///< Penetration depth (move shape 2 by this distance to resolve the collision)
+	float						mPenetrationDepth;			///< Penetration depth (move shape 2 by this distance to resolve the collision). If CollideShapeSettings::mMaxSeparationDistance > 0 this number can be negative to indicate that the objects are separated by -mPenetrationDepth. The contact points are the closest points in that case.
 	SubShapeID					mSubShapeID1;				///< Sub shape ID that identifies the face on shape 1
 	SubShapeID					mSubShapeID2;				///< Sub shape ID that identifies the face on shape 2
 	BodyID						mBodyID2;					///< BodyID to which shape 2 belongs to
@@ -95,7 +95,8 @@ class CollideShapeSettings : public CollideSettingsBase
 public:
 	JPH_OVERRIDE_NEW_DELETE
 
-	/// When > 0 contacts in the vicinity of the query shape can be found. All nearest contacts that are not further away than this distance will be found (unit: meter)
+	/// When > 0 contacts in the vicinity of the query shape can be found. All nearest contacts that are not further away than this distance will be found.
+	/// Note that in this case CollideShapeResult::mPenetrationDepth can become negative to indicate that objects are not overlapping. (unit: meter)
 	float						mMaxSeparationDistance		= 0.0f;
 
 	/// How backfacing triangles should be treated