diff --git a/src/p_map.cpp b/src/p_map.cpp
index 564b79b933..9700eda4e3 100644
--- a/src/p_map.cpp
+++ b/src/p_map.cpp
@@ -2945,7 +2945,7 @@ const secplane_t * P_CheckSlopeWalk(AActor *actor, DVector2 &move)
 		double t;
 
 		dest = actor->Pos() + move;
-		t = plane->fA() * dest.X + plane->fB() * dest.Y + plane->fC() * actor->Z() + plane->fD();
+		t = (plane->Normal() | DVector3(dest, actor->Z())) + plane->fD();
 		if (t < 0)
 		{ // Desired location is behind (below) the plane
 			// (i.e. Walking up the plane)
@@ -2979,16 +2979,16 @@ const secplane_t * P_CheckSlopeWalk(AActor *actor, DVector2 &move)
 					}
 					if (dopush)
 					{
-						actor->Vel.X = move.X = plane->fA() * 2;
-						actor->Vel.Y = move.Y = plane->fB() * 2;
+						move = plane->Normal() * 2;
+						actor->Vel.X = move.X;
+						actor->Vel.Y = move.Y;
 					}
 					return (actor->floorsector == actor->Sector) ? plane : NULL;
 				}
 			}
 			// Slide the desired location along the plane's normal
 			// so that it lies on the plane's surface
-			dest.X -= plane->fA() * t;
-			dest.Y -= plane->fB() * t;
+			dest -= plane->Normal() * t;
 			move = dest - actor->Pos().XY();
 			return (actor->floorsector == actor->Sector) ? plane : NULL;
 		}
@@ -2998,8 +2998,7 @@ const secplane_t * P_CheckSlopeWalk(AActor *actor, DVector2 &move)
 			{ 
 				// Actor's current spot is on/in the plane, so walk down it
 				// Same principle as walking up, except reversed
-				dest.X += plane->fA() * t;
-				dest.Y += plane->fB() * t;
+				dest += plane->Normal() * t;
 				move = dest - actor->Pos().XY();
 				return (actor->floorsector == actor->Sector) ? plane : NULL;
 			}
diff --git a/src/p_sectors.cpp b/src/p_sectors.cpp
index 55625c9c50..11ee3178ef 100644
--- a/src/p_sectors.cpp
+++ b/src/p_sectors.cpp
@@ -1086,11 +1086,11 @@ bool secplane_t::CopyPlaneIfValid (secplane_t *dest, const secplane_t *opp) cons
 
 	// If the planes do not have matching slopes, then always copy them
 	// because clipping would require creating new sectors.
-	if (fA() != dest->fA() || fB() != dest->fB() || fC() != dest->fC())
+	if (Normal() != dest->Normal())
 	{
 		copy = true;
 	}
-	else if (opp->fA() != -dest->fA() || opp->fB() != -dest->fB() || opp->fC() != -dest->fC())
+	else if (opp->Normal() != -dest->Normal())
 	{
 		if (fD() < dest->fD())
 		{
diff --git a/src/p_trace.cpp b/src/p_trace.cpp
index b5346d96d1..dabc92110e 100644
--- a/src/p_trace.cpp
+++ b/src/p_trace.cpp
@@ -877,11 +877,11 @@ bool FTraceInfo::TraceTraverse (int ptflags)
 
 bool FTraceInfo::CheckPlane (const secplane_t &plane)
 {
-	double den = plane.fA() * Vec.X + plane.fB() * Vec.Y + plane.fC() * Vec.Z;
+	double den = plane.Normal() | Vec;
 
 	if (den != 0)
 	{
-		double num = plane.fA() * Start.X + plane.fB() * Start.Y + plane.fC() * Start.Z + plane.fD();
+		double num = (plane.Normal() | Start) + plane.fD();
 
 		double hitdist = -num / den;
 
diff --git a/src/r_defs.h b/src/r_defs.h
index 81e6ec4b9f..c70cd1b5e0 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -302,14 +302,6 @@ public:
 		D = dd;
 	}
 
-	double fA() const
-	{
-		return normal.X;
-	}
-	double fB() const
-	{
-		return normal.Y;
-	}
 	double fC() const
 	{
 		return normal.Z;