Core/Maps: Moved min height calculation to worldserver for more precise results

Closes #16530

1 files changed, 58 insertions, 10 deletions

diff --git a/src/server/game/Maps/Map.cpp b/src/server/game/Maps/Map.cpp
index 1560d4bdd08..1e8f8fb81c3 100644
--- a/src/server/game/Maps/Map.cpp
+++ b/src/server/game/Maps/Map.cpp
@@ -37,7 +37,7 @@
 #include "VMapFactory.h"
 
 u_map_magic MapMagic        = { {'M','A','P','S'} };
-u_map_magic MapVersionMagic = { {'v','1','.','7'} };
+u_map_magic MapVersionMagic = { {'v','1','.','8'} };
 u_map_magic MapAreaMagic    = { {'A','R','E','A'} };
 u_map_magic MapHeightMagic  = { {'M','H','G','T'} };
 u_map_magic MapLiquidMagic  = { {'M','L','I','Q'} };
@@ -1805,10 +1805,10 @@ bool GridMap::loadHeightData(FILE* in, uint32 offset, uint32 /*size*/)
 
     if (header.flags & MAP_HEIGHT_HAS_FLIGHT_BOUNDS)
     {
-        _maxHeight = new float[16 * 16];
-        _minHeight = new float[16 * 16];
-        if (fread(_maxHeight, sizeof(float), 16 * 16, in) != 16 * 16 ||
-            fread(_minHeight, sizeof(float), 16 * 16, in) != 16 * 16)
+        _maxHeight = new int16[3 * 3];
+        _minHeight = new int16[3 * 3];
+        if (fread(_maxHeight, sizeof(int16), 3 * 3, in) != 3 * 3 ||
+            fread(_minHeight, sizeof(int16), 3 * 3, in) != 3 * 3)
             return false;
     }
 
@@ -2087,11 +2087,59 @@ float GridMap::getMinHeight(float x, float y) const
     if (!_minHeight)
         return -500.0f;
 
-    x = 16 * (CENTER_GRID_ID - x / SIZE_OF_GRIDS);
-    y = 16 * (CENTER_GRID_ID - y / SIZE_OF_GRIDS);
-    int lx = (int)x & 15;
-    int ly = (int)y & 15;
-    return _minHeight[lx * 16 + ly];
+    static uint32 const indices[] =
+    {
+        3, 0, 4,
+        0, 1, 4,
+        1, 2, 4,
+        2, 5, 4,
+        5, 8, 4,
+        8, 7, 4,
+        7, 6, 4,
+        6, 3, 4
+    };
+
+    static float const boundGridCoords[] =
+    {
+        0.0f, 0.0f,
+        0.0f, -266.66666f,
+        0.0f, -533.33331f,
+        -266.66666f, 0.0f,
+        -266.66666f, -266.66666f,
+        -266.66666f, -533.33331f,
+        -533.33331f, 0.0f,
+        -533.33331f, -266.66666f,
+        -533.33331f, -533.33331f
+    };
+
+    Cell cell(x, y);
+    float gx = x - (int32(cell.GridX()) - CENTER_GRID_ID + 1) * SIZE_OF_GRIDS;
+    float gy = y - (int32(cell.GridY()) - CENTER_GRID_ID + 1) * SIZE_OF_GRIDS;
+
+    uint32 quarterIndex = 0;
+    if (cell.CellY() < MAX_NUMBER_OF_CELLS / 2)
+    {
+        if (cell.CellX() < MAX_NUMBER_OF_CELLS / 2)
+        {
+            quarterIndex = 4 + (gy > gx);
+        }
+        else
+            quarterIndex = 2 + ((-SIZE_OF_GRIDS - gx) > gy);
+    }
+    else if (cell.CellX() < MAX_NUMBER_OF_CELLS / 2)
+    {
+        quarterIndex = 6 + ((-SIZE_OF_GRIDS - gx) <= gy);
+    }
+    else
+        quarterIndex = gx > gy;
+
+    quarterIndex *= 3;
+
+    return G3D::Plane(
+        G3D::Vector3(boundGridCoords[indices[quarterIndex + 0] * 2 + 0], boundGridCoords[indices[quarterIndex + 0] * 2 + 1], _minHeight[indices[quarterIndex + 0]]),
+        G3D::Vector3(boundGridCoords[indices[quarterIndex + 1] * 2 + 0], boundGridCoords[indices[quarterIndex + 1] * 2 + 1], _minHeight[indices[quarterIndex + 1]]),
+        G3D::Vector3(boundGridCoords[indices[quarterIndex + 2] * 2 + 0], boundGridCoords[indices[quarterIndex + 2] * 2 + 1], _minHeight[indices[quarterIndex + 2]])
+    ).distance(G3D::Vector3(gx, gy, 0.0f));
 }
 
 float GridMap::getLiquidLevel(float x, float y) const