Enable trigger collision fix for NPCs also

szapp · Jan 12, 2019 · f6de915 · f6de915
1 parent 8e4ad5c
commit f6de915
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Showing 4 changed files with 56 additions and 1 deletion.
diff --git a/_work/data/Scripts/Content/GFA/_intern/collision.d b/_work/data/Scripts/Content/GFA/_intern/collision.d
@@ -561,7 +561,8 @@ func void GFA_ExtendCollisionCheck() {
         };
 
         // Ignore by refined collision check with NPCs
-        if (GFA_Flags & GFA_RANGED) && (hit) {
+        var C_Npc shooter; shooter = _^(MEM_ReadInt(arrowAI+oCAIArrow_origin_offset));
+        if (GFA_Flags & GFA_RANGED) && (hit) && (Npc_IsPlayer(shooter)) {
             hit = GFA_RefinedProjectileCollisionCheck(vobPtr, arrowAI);
         };
     } else if (GFA_Flags & GFA_CUSTOM_COLLISIONS) && (GFA_TRIGGER_COLL_FIX) && (GOTHIC_BASE_VERSION == 2) {
@@ -583,3 +584,51 @@ func void GFA_ExtendCollisionCheck() {
         ECX = 0;
     };
 };
+
+
+/*
+ * Enable extended collision check for NPCs also. This function rewrites the opcode of oCAIArrow::CanThisCollideWith()
+ * such that the ignore list check and the hook GFA_ExtendCollisionCheck() are also executed for NPCs. This fixes the
+ * trigger collision bug for NPCs. Only implemented for Gothic 2, as the trigger bug does not exist in Gothic 1.
+ */
+func void GFA_ExtendCollisionCheckNpc() {
+    if (IsHooked(oCAIArrow__CanThisCollideWith_positive)) || (GOTHIC_BASE_VERSION != 2) {
+        return;
+    };
+
+    // Skip checks for shooter and target
+    MemoryProtectionOverride(oCAIArrow__CanThisCollideWith_skipCheck, 2);
+    MEM_WriteByte(oCAIArrow__CanThisCollideWith_skipCheck,   /*EB*/ 235);             // jmp     0x6A14F0
+    MEM_WriteByte(oCAIArrow__CanThisCollideWith_skipCheck+1, /*5A*/  90);             //         0x6A14F0-0x6A1494-2
+
+    // Re-add these checks later (after ignore list iteration and Daedalus hook)
+    ASM_Open(42);
+    // Check if extended detection returned zero
+    ASM_1(/*85*/ 133); ASM_1(/*C9*/ 201);                                             // test    ecx, ecx
+    ASM_1(/*74*/ 116); ASM_1(/*1D*/  29);                                             // jz      .continue
+    // Check if shooter is player
+    ASM_1(/*51*/  81);                                                                // push    ecx
+    ASM_1(/*8B*/ 139); ASM_1(/*4F*/  79); ASM_1(/*5C*/  92);                          // mov     ecx, [edi+0x5C]
+    ASM_1(/*8B*/ 139); ASM_1(/*01*/   1);                                             // mov     eax, [ecx]
+    ASM_1(/*FF*/ 255); ASM_1(/*90*/ 144); ASM_4(/*100*/256);                          // call    DWORD [eax+0x100]
+    ASM_1(/*59*/  89);                                                                // pop     ecx
+    ASM_1(/*85*/ 133); ASM_1(/*C0*/ 192);                                             // test    eax, eax
+    ASM_1(/*75*/ 117); ASM_1(/*0C*/  12);                                             // jnz     .continue
+    // Check if arrow AI has target
+    ASM_1(/*8B*/ 139); ASM_1(/*47*/  71); ASM_1(/*64*/ 100);                          // mov     eax, [edi+0x64]
+    ASM_1(/*85*/ 133); ASM_1(/*C0*/ 192);                                             // test    eax, eax
+    ASM_1(/*74*/ 116); ASM_1(/*05*/   5);                                             // jz      .continue
+    ASM_1(/*E9*/ 233); ASM_4(oCAIArrow__CanThisCollideWith_npcShooter-ASM_Here()-4);  // jmp     0x6A14AA
+    // .continue:
+    ASM_1(/*5F*/  95);                                                                // pop     edi
+    ASM_1(/*5E*/  94);                                                                // pop     esi
+    ASM_1(/*8B*/ 139); ASM_1(/*C1*/ 193);                                             // mov     eax, ecx
+    ASM_1(/*C2*/ 194); ASM_1(/*04*/   4); ASM_1(/*00*/   0);                          // ret     4
+
+    // Need absolute jump here, because Daedalus hook later relocates this jump
+    MemoryProtectionOverride(oCAIArrow__CanThisCollideWith_positive, 7);
+    MEM_WriteByte(oCAIArrow__CanThisCollideWith_positive,   /*B8*/ 184);              // mov eax, newCheck
+    MEM_WriteInt(oCAIArrow__CanThisCollideWith_positive+1,  ASM_Close());
+    MEM_WriteByte(oCAIArrow__CanThisCollideWith_positive+5, /*FF*/ 255);              // jmp eax
+    MEM_WriteByte(oCAIArrow__CanThisCollideWith_positive+6, /*E0*/ 224);
+};
diff --git a/_work/data/Scripts/Content/GFA/_intern/init.d b/_work/data/Scripts/Content/GFA/_intern/init.d
@@ -55,6 +55,7 @@ func void GFA_InitFeatureFreeAiming() {
         HookEngineF(oCAIArrow__ReportCollisionToAI_hitChc, 6, GFA_OverwriteHitChance); // Manipulate hit chance
         MemoryProtectionOverride(oCAIHuman__CheckFocusVob_ranged, 1); // Prevent toggling focus in ranged combat
         HookEngineF(zCModel__CalcModelBBox3DWorld_rtn, 6, GFA_EnlargeHumanModelBBox); // Include head in model bbox
+        GFA_ExtendCollisionCheckNpc();
         HookEngineF(oCAIArrow__CanThisCollideWith_positive, MEMINT_SwitchG1G2(6, 7), GFA_ExtendCollisionCheck);
         if (GFA_STRAFING) {
             HookEngineF(oCAIHuman__BowMode_rtn, 7, GFA_RangedLockMovement); // Allow strafing or not when falling
@@ -221,6 +222,7 @@ func void GFA_InitFeatureCustomCollisions() {
 
     // Extend and refine collision detection on vobs
     if ((GFA_COLL_PRIOR_NPC == -1) || ((GFA_TRIGGER_COLL_FIX) && (GOTHIC_BASE_VERSION == 2))) {
+        GFA_ExtendCollisionCheckNpc();
         HookEngineF(oCAIArrow__CanThisCollideWith_positive, MEMINT_SwitchG1G2(6, 7), GFA_ExtendCollisionCheck);
     };
 };

diff --git a/_work/data/Scripts/Content/GFA/_intern/offsets_G1.d b/_work/data/Scripts/Content/GFA/_intern/offsets_G1.d
@@ -103,6 +103,8 @@ const int oCAIArrowBase__ReportCollisionToAI_PFXon2  =  0;
 const int oCAIArrowBase__ReportCollisionToAI_collNpc =  0;                                 // Does not exist in Gothic 1
 const int oCAIArrow__ReportCollisionToAI_destroyPrj  =  6396025; //0x619879
 const int oCAIArrow__ReportCollisionToAI_keepPlyStrp =  6395401; //0x619609
+const int oCAIArrow__CanThisCollideWith_skipCheck    =  0;                                 // Not used for Gothic 1
+const int oCAIArrow__CanThisCollideWith_npcShooter   =  0;                                 // Not used for Gothic 1
 const int oCAIHuman__MagicMode_g2ctrlCheck           =  0;                                 // Does not exist in Gothic 1
 const int oCAIHuman__BowMode_g2ctrlCheck             =  0;                                 // Does not exist in Gothic 1
 const int oCAIHuman__BowMode_shootingKey             =  6359374; //0x61094E                // Not used for Gothic 1

diff --git a/_work/data/Scripts/Content/GFA/_intern/offsets_G2.d b/_work/data/Scripts/Content/GFA/_intern/offsets_G2.d
@@ -103,6 +103,8 @@ const int oCAIArrowBase__ReportCollisionToAI_PFXon2  =  6949396; //0x6A0A14
 const int oCAIArrowBase__ReportCollisionToAI_collNpc =  6949734; //0x6A0B66
 const int oCAIArrow__ReportCollisionToAI_destroyPrj  =  0;                                 // Does not exist in Gothic 2
 const int oCAIArrow__ReportCollisionToAI_keepPlyStrp =  0;                                 // Does not exist in Gothic 2
+const int oCAIArrow__CanThisCollideWith_skipCheck    =  6952084; //0x6A1494
+const int oCAIArrow__CanThisCollideWith_npcShooter   =  6952106; //0x6A14AA
 const int oCAIHuman__MagicMode_g2ctrlCheck           =  4665380; //0x473024
 const int oCAIHuman__BowMode_g2ctrlCheck             =  6905643; //0x695F2B
 const int oCAIHuman__BowMode_shootingKey             =  6906610; //0x6962F2