Index: source/renderer/WaterManager.cpp
===================================================================
--- source/renderer/WaterManager.cpp
+++ source/renderer/WaterManager.cpp
@@ -417,71 +417,98 @@
 // Calculate our binary heightmap from the terrain heightmap.
 void WaterManager::RecomputeDistanceHeightmap()
 {
-	size_t SideSize = m_MapSize*2;
+	size_t SideSize = m_MapSize;
 	if (m_DistanceHeightmap == NULL)
+	{
 		m_DistanceHeightmap = new float[SideSize*SideSize];
+		memset(m_DistanceHeightmap, 0, sizeof(float) * SideSize*SideSize);
+	}
 
 	CTerrain* terrain = g_Game->GetWorld()->GetTerrain();
 
 	// Create a manhattan-distance heightmap.
-	// This is currently upsampled by a factor of 2 to get more precision
 	// This could be refined to only be done near the coast itself, but it's probably not necessary.
 
+	// we don't consider values above maxLevel so this is effectively our lookahead.
+	const size_t maxLevel = 5;
+
+	u16* heightmap = terrain->GetHeightMap();
+
+	auto aboveWater = [&heightmap, &SideSize, this](int x, int z) -> bool { return HEIGHT_SCALE * heightmap[z*SideSize + x] >= m_WaterHeight; };
+	auto updateLookaheadX = [&SideSize, &maxLevel, &aboveWater](size_t& lookahead, int x, int z) -> void
+	{
+		for (size_t i = lookahead; i <= x+maxLevel; ++i)
+		{
+			if (lookahead < SideSize && aboveWater(lookahead, z))
+				break;
+			++lookahead;
+		};
+	};
 	for (size_t z = 0; z < SideSize; ++z)
 	{
-		float level = SideSize;
+		size_t level = aboveWater(0, z) ? 0 : maxLevel;
+		size_t lookahead = level > 0 ? 1 : 0;
+
+		updateLookaheadX(lookahead, 0, z);
+
+		// start moving
 		for (size_t x = 0; x < SideSize; ++x)
-			m_DistanceHeightmap[z*SideSize + x] = terrain->GetExactGroundLevel(x*2, z*2) >= m_WaterHeight ? level = 0.f : ++level;
-		level = SideSize;
-		for (size_t x = SideSize-1; x != (size_t)-1; --x)
 		{
-			if (terrain->GetExactGroundLevel(x*2, z*2) >= m_WaterHeight)
-				level = 0.f;
+			// increment past value
+			if (aboveWater(x, z))
+				level = 0;
 			else
-			{
-				++level;
-				if (level < m_DistanceHeightmap[z*SideSize + x])
-					m_DistanceHeightmap[z*SideSize + x] = level;
-			}
+				level = std::min(level+1, maxLevel);
+
+			// move lookahead
+			if (lookahead == x)
+				++lookahead;
+			updateLookaheadX(lookahead, x, z);
+
+			m_DistanceHeightmap[z*SideSize + x] = std::min(lookahead-x, level);
 		}
 	}
+	// same process on the z-axis
+	auto updateLookaheadZ = [&SideSize, &maxLevel, &aboveWater](size_t& lookahead, int x, int z) -> void
+	{
+		for (size_t i = lookahead; i <= z+maxLevel; ++i)
+		{
+			if (lookahead < SideSize && aboveWater(x, lookahead))
+				break;
+			++lookahead;
+		};
+	};
 	for (size_t x = 0; x < SideSize; ++x)
 	{
-		float level = SideSize;
+		size_t level = aboveWater(x, 0) ? 0 : maxLevel;
+		size_t lookahead = level > 0 ? 1 : 0;
+
+		updateLookaheadZ(lookahead, x, 0);
+
 		for (size_t z = 0; z < SideSize; ++z)
 		{
-			if (terrain->GetExactGroundLevel(x*2, z*2) >= m_WaterHeight)
-				level = 0.f;
-			else if (level > m_DistanceHeightmap[z*SideSize + x])
-				level = m_DistanceHeightmap[z*SideSize + x];
-			else
-			{
-				++level;
-				if (level < m_DistanceHeightmap[z*SideSize + x])
-					m_DistanceHeightmap[z*SideSize + x] = level;
-			}
-		}
-		level = SideSize;
-		for (size_t z = SideSize-1; z != (size_t)-1; --z)
-		{
-			if (terrain->GetExactGroundLevel(x*2, z*2) >= m_WaterHeight)
-				level = 0.f;
-			else if (level > m_DistanceHeightmap[z*SideSize + x])
-				level = m_DistanceHeightmap[z*SideSize + x];
+			if (aboveWater(x, z))
+				level = 0;
 			else
-			{
-				++level;
-				if (level < m_DistanceHeightmap[z*SideSize + x])
-					m_DistanceHeightmap[z*SideSize + x] = level;
-			}
+				level = std::min(level+1, maxLevel);
+
+			// move lookahead
+			if (lookahead == z)
+				++lookahead;
+			updateLookaheadZ(lookahead, x, z);
+
+			m_DistanceHeightmap[z*SideSize + x] = std::min(m_DistanceHeightmap[z*SideSize + x], (float)std::min(lookahead-z, level));
 		}
-	}
-}
+	}}
 
 // This requires m_DistanceHeightmap to be defined properly.
 void WaterManager::CreateWaveMeshes()
 {
-	size_t SideSize = m_MapSize*2;
+	size_t SideSize = m_MapSize;
+
+	if (m_MapSize == 0)
+		return;
+
 	CTerrain* terrain = g_Game->GetWorld()->GetTerrain();
 
 	for (WaveObject* const& obj : m_ShoreWaves)
@@ -503,10 +530,11 @@
 
 	// First step: get the points near the coast.
 	std::set<int> CoastalPointsSet;
-	for (size_t z = 1; z < SideSize-1; ++z)
-		for (size_t x = 1; x < SideSize-1; ++x)
-			if (fabs(m_DistanceHeightmap[z*SideSize + x]-1.0f) < 0.2f)
-				CoastalPointsSet.insert(z*SideSize + x);
+	for (size_t z = 1; z < m_MapSize - 1; ++z)
+		for (size_t x = 1; x < m_MapSize - 1; ++x)
+			// get the points not on the shore but near it, ocean-side
+			if (m_DistanceHeightmap[z*m_MapSize + x] > 0.5f && m_DistanceHeightmap[z*m_MapSize + x] < 1.5f)
+				CoastalPointsSet.insert((z)*SideSize + x);
 
 	// Second step: create chains out of those coastal points.
 	static const int around[8][2] = { { -1,-1 }, { -1,0 }, { -1,1 }, { 0,1 }, { 1,1 }, { 1,0 }, { 1,-1 }, { 0,-1 } };
@@ -520,7 +548,7 @@
 
 		std::deque<CoastalPoint> Chain;
 
-		Chain.push_front(CoastalPoint(index,CVector2D(x*2,y*2)));
+		Chain.push_front(CoastalPoint(index,CVector2D(x*4,y*4)));
 
 		// Erase us.
 		CoastalPointsSet.erase(CoastalPointsSet.begin());
@@ -554,9 +582,9 @@
 			int endedChain = false;
 
 			if (i == 0)
-				Chain.push_back(CoastalPoint(indexx,CVector2D(xx*2,yy*2)));
+				Chain.push_back(CoastalPoint(indexx,CVector2D(xx*4,yy*4)));
 			else
-				Chain.push_front(CoastalPoint(indexx,CVector2D(xx*2,yy*2)));
+				Chain.push_front(CoastalPoint(indexx,CVector2D(xx*4,yy*4)));
 
 			// If there's a loop we'll be the "other" neighboring point already so check for that.
 			// We'll readd at the end/front the other one to have full squares.
@@ -586,9 +614,9 @@
 						yy = yy + around[p][1];
 						indexx = xx + yy*SideSize;
 						if (i == 0)
-							Chain.push_back(CoastalPoint(indexx,CVector2D(xx*2,yy*2)));
+							Chain.push_back(CoastalPoint(indexx,CVector2D(xx*4,yy*4)));
 						else
-							Chain.push_front(CoastalPoint(indexx,CVector2D(xx*2,yy*2)));
+							Chain.push_front(CoastalPoint(indexx,CVector2D(xx*4,yy*4)));
 						CoastalPointsSet.erase(xx + yy*SideSize);
 						found = true;
 						break;
@@ -723,7 +751,7 @@
 				j += 3;
 				continue;
 			}
-			outmost = -0.5f + outmost * m_Waviness/10.0f;
+			outmost = -2.5f + outmost * m_Waviness/10.0f;
 
 			avgDepth /= width;
 
Index: source/simulation2/components/CCmpWaterManager.cpp
===================================================================
--- source/simulation2/components/CCmpWaterManager.cpp
+++ source/simulation2/components/CCmpWaterManager.cpp
@@ -97,7 +97,6 @@
 	{
 		if (CRenderer::IsInitialised())
 		{
-			g_Renderer.GetWaterManager()->RecomputeBlurredNormalMap();
 			g_Renderer.GetWaterManager()->RecomputeDistanceHeightmap();
 			g_Renderer.GetWaterManager()->RecomputeWindStrength();
 			g_Renderer.GetWaterManager()->CreateWaveMeshes();