From ef2294a1a426a044c40ab8183eae7f6ec260e489 Mon Sep 17 00:00:00 2001
From: Alexander Grund <Flamefire@users.noreply.github.com>
Date: Thu, 30 Apr 2020 12:39:01 +0200
Subject: [PATCH] Fix drawing of harbor textures

---
 CMap.cpp     | 4 ++--
 CSurface.cpp | 5 +++++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/CMap.cpp b/CMap.cpp
index d8e667e..773cbac 100644
--- a/CMap.cpp
+++ b/CMap.cpp
@@ -1751,7 +1751,7 @@ void CMap::modifyHeightMakeBigHouse(int VertexX, int VertexY)
        || middleVertex.rsuTexture == TRIANGLE_TEXTURE_STEPPE_MEADOW2_HARBOUR || middleVertex.rsuTexture == TRIANGLE_TEXTURE_FLOWER_HARBOUR
        || middleVertex.rsuTexture == TRIANGLE_TEXTURE_MINING_MEADOW_HARBOUR)
     {
-        middleVertex.rsuTexture -= 0x40;
+        middleVertex.rsuTexture &= ~0x40;
     }
 }
 
@@ -1848,7 +1848,7 @@ void CMap::modifyTextureMakeHarbour(int VertexX, int VertexY)
        || vertex.rsuTexture == TRIANGLE_TEXTURE_STEPPE_MEADOW2 || vertex.rsuTexture == TRIANGLE_TEXTURE_FLOWER
        || vertex.rsuTexture == TRIANGLE_TEXTURE_MINING_MEADOW)
     {
-        vertex.rsuTexture += 0x40;
+        vertex.rsuTexture |= 0x40;
     }
 }
 
diff --git a/CSurface.cpp b/CSurface.cpp
index 4aef71e..4a4acc4 100644
--- a/CSurface.cpp
+++ b/CSurface.cpp
@@ -403,6 +403,11 @@ enum class BorderPreference
 BorderPreference CalcBorders(const bobMAP& map, Uint8 s2Id1, Uint8 s2Id2, SDL_Rect& borderRect)
 {
     // we have to decide which border to blit, "left or right" or "top or bottom"
+    s2Id1 &= ~(0x40 | 0x80);
+    s2Id2 &= ~(0x40 | 0x80);
+
+    assert(s2Id1 < map.s2IdToTerrain.size());
+    assert(s2Id2 < map.s2IdToTerrain.size());
 
     DescIdx<TerrainDesc> idxTop = map.s2IdToTerrain[s2Id1];
     DescIdx<TerrainDesc> idxBottom = map.s2IdToTerrain[s2Id2];