From 2bafab723394a741be0876795ec7c658ee28bcab Mon Sep 17 00:00:00 2001
From: mjagdis <mjagdis@eris-associates.co.uk>
Date: Fri, 1 Nov 2024 22:17:27 +0000
Subject: Fix access to uninitialized space (#5576)

* Fix access to uninitialized space

Signed-off-by: Mike Jagdis <mjagdis@eris-associates.co.uk>

* Same fix to other noise generate functions

Signed-off-by: Mike Jagdis <mjagdis@eris-associates.co.uk>

* Skip the last Cell.Move

Signed-off-by: Mike Jagdis <mjagdis@eris-associates.co.uk>

* Add comments

Signed-off-by: Mike Jagdis <mjagdis@eris-associates.co.uk>

---------

Signed-off-by: Mike Jagdis <mjagdis@eris-associates.co.uk>
---
 src/Noise/InterpolNoise.h | 27 ++++++++++++++++++---------
 src/Noise/Noise.cpp       | 45 ++++++++++++++++++++++++++++++---------------
 2 files changed, 48 insertions(+), 24 deletions(-)

diff --git a/src/Noise/InterpolNoise.h b/src/Noise/InterpolNoise.h
index 447796739..12b167dbe 100644
--- a/src/Noise/InterpolNoise.h
+++ b/src/Noise/InterpolNoise.h
@@ -427,28 +427,37 @@ public:
 
 		// Calculate query values using Cell:
 		int FromZ = 0;
-		for (int z = 0; z < NumSameZ; z++)
+		for (int z = 0; z < NumSameZ;)
 		{
 			int ToZ = FromZ + SameZ[z];
 			int CurFloorZ = FloorZ[FromZ];
 			int FromY = 0;
-			for (int y = 0; y < NumSameY; y++)
+			for (int y = 0; y < NumSameY;)
 			{
 				int ToY = FromY + SameY[y];
 				int CurFloorY = FloorY[FromY];
 				int FromX = 0;
-				for (int x = 0; x < NumSameX; x++)
+				for (int x = 0; x < NumSameX;)
 				{
 					int ToX = FromX + SameX[x];
 					Cell.Generate(FromX, ToX, FromY, ToY, FromZ, ToZ);
-					Cell.Move(FloorX[ToX], CurFloorY, CurFloorZ);
-					FromX = ToX;
+					if (++x < NumSameX)  // Call Move() every time except for the last loop iteration
+					{
+						Cell.Move(FloorX[ToX], CurFloorY, CurFloorZ);
+						FromX = ToX;
+					}
+				}
+				if (++y < NumSameY)  // Call Move() every time except for the last loop iteration
+				{
+					Cell.Move(FloorX[0], FloorY[ToY], CurFloorZ);
+					FromY = ToY;
 				}
-				Cell.Move(FloorX[0], FloorY[ToY], CurFloorZ);
-				FromY = ToY;
 			}  // for y
-			Cell.Move(FloorX[0], FloorY[0], FloorZ[ToZ]);
-			FromZ = ToZ;
+			if (++z < NumSameZ)  // Call Move() every time except for the last loop iteration
+			{
+				Cell.Move(FloorX[0], FloorY[0], FloorZ[ToZ]);
+				FromZ = ToZ;
+			}
 		}  // for z
 	}
 
diff --git a/src/Noise/Noise.cpp b/src/Noise/Noise.cpp
index cbdc6bc72..136d124a0 100644
--- a/src/Noise/Noise.cpp
+++ b/src/Noise/Noise.cpp
@@ -734,20 +734,26 @@ void cCubicNoise::Generate2D(
 
 	// Calculate query values using Cell:
 	int FromY = 0;
-	for (int y = 0; y < NumSameY; y++)
+	for (int y = 0; y < NumSameY;)
 	{
 		int ToY = FromY + SameY[y];
 		int FromX = 0;
 		int CurFloorY = FloorY[FromY];
-		for (int x = 0; x < NumSameX; x++)
+		for (int x = 0; x < NumSameX;)
 		{
 			int ToX = FromX + SameX[x];
 			Cell.Generate(FromX, ToX, FromY, ToY);
-			Cell.Move(FloorX[ToX], CurFloorY);
-			FromX = ToX;
+			if (++x < NumSameX)  // Call Move() every time except for the last loop iteration
+			{
+				Cell.Move(FloorX[ToX], CurFloorY);
+				FromX = ToX;
+			}
+		}
+		if (++y < NumSameY)  // Call Move() every time except for the last loop iteration
+		{
+			Cell.Move(FloorX[0], FloorY[ToY]);
+			FromY = ToY;
 		}
-		Cell.Move(FloorX[0], FloorY[ToY]);
-		FromY = ToY;
 	}
 }
 
@@ -795,28 +801,37 @@ void cCubicNoise::Generate3D(
 
 	// Calculate query values using Cell:
 	int FromZ = 0;
-	for (int z = 0; z < NumSameZ; z++)
+	for (int z = 0; z < NumSameZ;)
 	{
 		int ToZ = FromZ + SameZ[z];
 		int CurFloorZ = FloorZ[FromZ];
 		int FromY = 0;
-		for (int y = 0; y < NumSameY; y++)
+		for (int y = 0; y < NumSameY;)
 		{
 			int ToY = FromY + SameY[y];
 			int CurFloorY = FloorY[FromY];
 			int FromX = 0;
-			for (int x = 0; x < NumSameX; x++)
+			for (int x = 0; x < NumSameX;)
 			{
 				int ToX = FromX + SameX[x];
 				Cell.Generate(FromX, ToX, FromY, ToY, FromZ, ToZ);
-				Cell.Move(FloorX[ToX], CurFloorY, CurFloorZ);
-				FromX = ToX;
+				if (++x < NumSameX)  // Call Move() every time except for the last loop iteration
+				{
+					Cell.Move(FloorX[ToX], CurFloorY, CurFloorZ);
+					FromX = ToX;
+				}
+			}
+			if (++y < NumSameY)  // Call Move() every time except for the last loop iteration
+			{
+				Cell.Move(FloorX[0], FloorY[ToY], CurFloorZ);
+				FromY = ToY;
 			}
-			Cell.Move(FloorX[0], FloorY[ToY], CurFloorZ);
-			FromY = ToY;
 		}  // for y
-		Cell.Move(FloorX[0], FloorY[0], FloorZ[ToZ]);
-		FromZ = ToZ;
+		if (++z < NumSameZ)  // Call Move() every time except for the last loop iteration
+		{
+			Cell.Move(FloorX[0], FloorY[0], FloorZ[ToZ]);
+			FromZ = ToZ;
+		}
 	}  // for z
 }
 
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