VoronoiMap: Added Jitter and OddRowOffset params.

src/VoronoiMap.cpp

@@ -10,11 +10,13 @@
 
 
 
-cVoronoiMap::cVoronoiMap(int a_Seed, int a_CellSize) :
+cVoronoiMap::cVoronoiMap(int a_Seed, int a_CellSize, int a_JitterSize) :
 	m_Noise1(a_Seed + 1),
 	m_Noise2(a_Seed + 2),
 	m_Noise3(a_Seed + 3),
-	m_CellSize(a_CellSize),
+	m_CellSize(std::max(a_CellSize, 2)),
+	m_JitterSize(Clamp(a_JitterSize, 1, a_CellSize)),
+	m_OddRowOffset(0),
 	m_CurrentCellX(9999999),  // Cell coords that are definitely out of the range for normal generator, so that the first query will overwrite them
 	m_CurrentCellZ(9999999)
 {
@@ -26,7 +28,29 @@ cVoronoiMap::cVoronoiMap(int a_Seed, int a_CellSize) :
 
 void cVoronoiMap::SetCellSize(int a_CellSize)
 {
+	a_CellSize = std::max(a_CellSize, 2);  // Cell size must be at least 2
 	m_CellSize = a_CellSize;
+
+	// For compatibility with previous version, which didn't have the jitter, we set jitter here as well.
+	m_JitterSize = a_CellSize;
+}
+
+
+
+
+
+void cVoronoiMap::SetJitterSize(int a_JitterSize)
+{
+	m_JitterSize = Clamp(a_JitterSize, 1, m_CellSize);
+}
+
+
+
+
+
+void cVoronoiMap::SetOddRowOffset(int a_OddRowOffset)
+{
+	m_OddRowOffset = Clamp(a_OddRowOffset, -m_CellSize, m_CellSize);
 }
 
 
@@ -111,12 +135,13 @@ void cVoronoiMap::UpdateCell(int a_CellX, int a_CellZ)
 	for (int x = 0; x < 5; x++)
 	{
 		int BaseX = (NoiseBaseX + x) * m_CellSize;
+		int OddRowOffset = ((NoiseBaseX + x) & 0x01) * m_OddRowOffset;
 		for (int z = 0; z < 5; z++)
 		{
-			int OffsetX = (m_Noise1.IntNoise2DInt(NoiseBaseX + x, NoiseBaseZ + z) / 8) % m_CellSize;
+			int OffsetX = (m_Noise1.IntNoise2DInt(NoiseBaseX + x, NoiseBaseZ + z) / 8) % m_JitterSize;
-			int OffsetZ = (m_Noise2.IntNoise2DInt(NoiseBaseX + x, NoiseBaseZ + z) / 8) % m_CellSize;
+			int OffsetZ = (m_Noise2.IntNoise2DInt(NoiseBaseX + x, NoiseBaseZ + z) / 8) % m_JitterSize;
 			m_SeedX[x][z] = BaseX + OffsetX;
-			m_SeedZ[x][z] = (NoiseBaseZ + z) * m_CellSize + OffsetZ;
+			m_SeedZ[x][z] = (NoiseBaseZ + z) * m_CellSize + OddRowOffset + OffsetZ;
 		}  // for z
 	}  // for x
 	m_CurrentCellX = a_CellX;

src/VoronoiMap.h

@@ -18,18 +18,28 @@
 class cVoronoiMap
 {
 public:
-	cVoronoiMap(int a_Seed, int a_CellSize = 128);
+	cVoronoiMap(int a_Seed, int a_CellSize = 128, int a_JitterSize = 128);
 	
-	/// Sets the cell size used for generating the Voronoi seeds
+	/** Sets both the cell size and jitter size used for generating the Voronoi seeds. */
 	void SetCellSize(int a_CellSize);
+
+	/** Sets the jitter size. Clamps it to current cell size. */
+	void SetJitterSize(int a_JitterSize);
+
+	/** Sets the offset that is added to each odd row of cells.
+	This offset makes the voronoi cells align to a non-grid.
+	Clamps the value to [-m_CellSize, +m_CellSize]. */
+	void SetOddRowOffset(int a_OddRowOffset);
 	
-	/// Returns the value in the cell into which the specified point lies
+	/** Returns the value in the cell into which the specified point lies. */
 	int GetValueAt(int a_X, int a_Y);
 	
-	/// Returns the value in the cell into which the specified point lies, and the distance to the nearest Voronoi seed
+	/** Returns the value in the cell into which the specified point lies,
+	and the distance to the nearest Voronoi seed. */
 	int GetValueAt(int a_X, int a_Y, int & a_MinDistance);
 	
-	/// Returns the value in the cell into which the specified point lies, and the distances to the 2 nearest Voronoi seeds. Uses a cache
+	/** Returns the value in the cell into which the specified point lies,
+	and the distances to the 2 nearest Voronoi seeds. Uses a cache. */
 	int GetValueAt(int a_X, int a_Y, int & a_MinDistance1, int & a_MinDistance2);
 
 protected:
@@ -38,8 +48,17 @@ protected:
 	cNoise m_Noise2;
 	cNoise m_Noise3;
 	
-	/// Size of the Voronoi cells (avg X/Y distance between the seeds)
+	/** Size of the Voronoi cells (avg X/Y distance between the seeds). Expected to be at least 2. */
 	int m_CellSize;
+
+	/** The amount that the cell seeds may be offset from the grid.
+	Expected to be at least 1 and less than m_CellSize. */
+	int m_JitterSize;
+
+	/** The constant amount that the cell seeds of every odd row will be offset from the grid.
+	This allows us to have non-rectangular grids.
+	Expected to be between -m_CellSize and +m_CellSize. */
+	int m_OddRowOffset;
 	
 	/** The X coordinate of the currently cached cell neighborhood */
 	int m_CurrentCellX;