Ticket #1986: terrain.diff

source/graphics/Terrain.cpp

@@ -133 +133 @@
     ssize_t hj = clamp(j, (ssize_t)0, m_MapSize-1);
     u16 height = m_Heightmap[hj*m_MapSize + hi];
     pos.X = fixed::FromInt(i) * (int)TERRAIN_TILE_SIZE;
-    pos.Y = fixed::FromInt(height) / (int)HEIGHT_UNITS_PER_METRE;
+    // divide height by 2 to avoid overflows when height is between 2^15 and 2^16.
+    pos.Y = fixed::FromInt(height >> 1) / ((int)HEIGHT_UNITS_PER_METRE >> 1);
     pos.Z = fixed::FromInt(j) * (int)TERRAIN_TILE_SIZE;
 }