[Vanilla Fix] Fix the bug that ships can travel on elevated bridges (#1659)

Author: NetsuNegi

CREDITS.md

@@ -390,6 +390,7 @@ This page lists all the individual contributions to the project by their author.
   - Fix the bug that `AllowAirstrike=no` cannot completely prevent air strikes from being launched against it
   - Fix the bug that infantry ignored `Passengers` and `SizeLimit` when entering buildings
   - Tiberium eater logic
+  - Fix the bug that ships can travel on elevated bridges
 - **Apollo** - Translucent SHP drawing patches
 - **ststl**:
   - Customizable `ShowTimer` priority of superweapons

docs/Fixed-or-Improved-Logics.md

@@ -224,6 +224,7 @@ This page describes all ingame logics that are fixed or improved in Phobos witho
 - Fixed the issue where computer players did not search for new enemies after defeating them or forming alliances with them.
 - Fixed the bug that infantry ignored `Passengers` and `SizeLimit` when entering buildings.
 - Fixed `VoiceDeploy` not played, when deployed through hot-key/command bar.
+- Fixed the bug that ships can travel on elevated bridges.
 
 ## Fixes / interactions with other extensions
 

docs/Whats-New.md

@@ -395,6 +395,7 @@ Vanilla fixes:
 - Fixed the bug that buildings will always be tinted as airstrike owner (by NetsuNegi)
 - Fixed the issue where computer players did not search for new enemies after defeating them or forming alliances with them (by FlyStar)
 - Fixed the bug that infantry ignored `Passengers` and `SizeLimit` when entering buildings (by NetsuNegi)
+- Fixed the bug that ships can travel on elevated bridges (by NetsuNegi)
 
 Phobos fixes:
 - Fixed the bug that `AllowAirstrike=no` cannot completely prevent air strikes from being launched against it (by NetsuNegi)

src/Misc/Hooks.BugFixes.cpp

@@ -1560,6 +1560,17 @@ DEFINE_HOOK(0x449462, BuildingClass_IsCellOccupied_UndeploysInto, 0x6)
 	return SkipGameCode;
 }
 
+DEFINE_HOOK(0x73FA92, UnitClass_IsCellOccupied_LandType, 0x8)
+{
+	enum { ContinueCheck = 0x73FC24, NoMove = 0x73FACD };
+
+	GET(UnitClass*, pThis, EBX);
+	GET(CellClass*, pCell, EDI);
+	GET_STACK(bool, containsBridge, STACK_OFFSET(0x90, -0x7D));
+
+	return GroundType::Array[static_cast<int>(containsBridge ? LandType::Road : pCell->LandType)].Cost[static_cast<int>(pThis->Type->SpeedType)] == 0.0f ? NoMove : ContinueCheck;
+}
+
 #pragma region XSurfaceFix
 
 // Fix a crash at 0x7BAEA1 when trying to access a point outside of surface bounds.