From ac793df2ab14a2b98504d9ea49bc4abcee828052 Mon Sep 17 00:00:00 2001
From: madmaxoft <github@xoft.cz>
Date: Wed, 27 Nov 2013 14:26:28 +0100
Subject: [PATCH] Added missing files for Voronoi map generation.

---
 src/VoronoiMap.cpp | 95 ++++++++++++++++++++++++++++++++++++++++++++++
 src/VoronoiMap.h   | 45 ++++++++++++++++++++++
 2 files changed, 140 insertions(+)
 create mode 100644 src/VoronoiMap.cpp
 create mode 100644 src/VoronoiMap.h

diff --git a/src/VoronoiMap.cpp b/src/VoronoiMap.cpp
new file mode 100644
index 00000000..e95cb0bf
--- /dev/null
+++ b/src/VoronoiMap.cpp
@@ -0,0 +1,95 @@
+
+// VoronoiMap.cpp
+
+// Implements the cVoronoiMap class that implements a Voronoi algorithm over a noise to produce a map
+
+#include "Globals.h"
+#include "VoronoiMap.h"
+
+
+
+
+
+cVoronoiMap::cVoronoiMap(int a_Seed, int a_CellSize) :
+	m_Noise(a_Seed * 13 + 7),
+	m_CellSize(a_CellSize)
+{
+}
+
+
+
+
+
+void cVoronoiMap::SetCellSize(int a_CellSize)
+{
+	m_CellSize = a_CellSize;
+}
+
+
+
+
+
+int cVoronoiMap::GetValueAt(int a_X, int a_Y)
+{
+	int MinDist1, MinDist2;
+	return GetValueAt(a_X, a_Y, MinDist1, MinDist2);
+}
+
+
+
+
+
+int cVoronoiMap::GetValueAt(int a_X, int a_Y, int & a_MinDist)
+{
+	int MinDist2;
+	return GetValueAt(a_X, a_Y, a_MinDist, MinDist2);
+}
+
+
+
+
+
+int cVoronoiMap::GetValueAt(int a_X, int a_Y, int & a_MinDist1, int & a_MinDist2)
+{
+	// Note that due to historical reasons, the algorithm uses XZ coords, while the input uses XY coords.
+	// This is because the algorithm was first implemented directly in the biome generators which use MC coords.
+	
+	int CellX = a_X / m_CellSize;
+	int CellZ = a_Y / m_CellSize;
+	
+	// Get 5x5 neighboring cell seeds, compare distance to each. Return the value in the minumim-distance cell
+	int MinDist = m_CellSize * m_CellSize * 16;  // There has to be a cell closer than this
+	int MinDist2 = MinDist;
+	int res = 0;  // Will be overriden
+	for (int x = CellX - 2; x <= CellX + 2; x++)
+	{
+		int BaseX = x * m_CellSize;
+		for (int z = CellZ - 2; z < CellZ + 2; z++)
+		{
+			int OffsetX = (m_Noise.IntNoise3DInt(x, 16 * x + 32 * z, z) / 8) % m_CellSize;
+			int OffsetZ = (m_Noise.IntNoise3DInt(x, 32 * x - 16 * z, z) / 8) % m_CellSize;
+			int SeedX = BaseX + OffsetX;
+			int SeedZ = z * m_CellSize + OffsetZ;
+			
+			int Dist = (SeedX - a_X) * (SeedX - a_X) + (SeedZ - a_Y) * (SeedZ - a_Y);
+			if (Dist < MinDist)
+			{
+				MinDist2 = MinDist;
+				MinDist = Dist;
+				res = m_Noise.IntNoise3DInt(x, x - z + 1000, z);
+			}
+			else if (Dist < MinDist2)
+			{
+				MinDist2 = Dist;
+			}
+		}  // for z
+	}  // for x
+
+	a_MinDist1 = MinDist;
+	a_MinDist2 = MinDist2;
+	return res;
+}
+
+
+
+
diff --git a/src/VoronoiMap.h b/src/VoronoiMap.h
new file mode 100644
index 00000000..bcd37f9c
--- /dev/null
+++ b/src/VoronoiMap.h
@@ -0,0 +1,45 @@
+
+// VoronoiMap.h
+
+// Declares the cVoronoiMap class that implements a Voronoi algorithm over a noise to produce a map
+
+
+
+
+
+#pragma once
+
+#include "Noise.h"
+
+
+
+
+
+class cVoronoiMap
+{
+public:
+	cVoronoiMap(int a_Seed, int a_CellSize = 128);
+	
+	/// Sets the cell size used for generating the Voronoi seeds
+	void SetCellSize(int a_CellSize);
+	
+	/// 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
+	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
+	int GetValueAt(int a_X, int a_Y, int & a_MinDistance1, int & a_MinDistance2);
+	
+protected:
+	/// The noise used for generating Voronoi seeds
+	cNoise m_Noise;
+	
+	/// Size of the Voronoi cells (avg X/Y distance between the seeds)
+	int m_CellSize;
+} ;
+
+
+
+