Make spear autoaim not prefer enemies

ori-community · May 31, 2024 · 32c2a94 · 32c2a94
1 parent 370291b
commit 32c2a94
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Showing 3 changed files with 36 additions and 3 deletions.
diff --git a/projects/Modloader/windows_api/memory.cpp b/projects/Modloader/windows_api/memory.cpp
@@ -47,4 +47,15 @@ namespace modloader::win::memory {
     uint64_t resolve_unity_player_rva(uint64_t rva) {
         return get_unity_player_address() + rva;
     }
+
+    void modify_memory(uint64_t address, uint64_t length, const std::function<void(uint8_t* memory)>& fn) {
+        auto out = 0UL;
+        const auto address_ptr = reinterpret_cast<void*>(address);
+        VirtualProtect(address_ptr, length, PAGE_EXECUTE_READWRITE, &out);
+
+        fn(reinterpret_cast<uint8_t*>(address));
+
+        VirtualProtect(address_ptr, length, PAGE_EXECUTE_READ, &out);
+        FlushInstructionCache(GetCurrentProcess(), address_ptr, length);
+    }
 } // namespace modloader::win::memory
diff --git a/projects/Modloader/windows_api/memory.h b/projects/Modloader/windows_api/memory.h
@@ -2,11 +2,17 @@
 
 #include <Modloader/macros.h>
 #include <cstdint>
+#include <functional>
 
 namespace modloader::win::memory {
+    enum class Instruction: uint8_t {
+        NOP = 0x90,
+    };
+
     IL2CPP_MODLOADER_DLLEXPORT uint64_t get_game_assembly_address();
     IL2CPP_MODLOADER_DLLEXPORT uint64_t get_unity_player_address();
     IL2CPP_MODLOADER_DLLEXPORT uint64_t resolve_rva(uint64_t rva);
     IL2CPP_MODLOADER_DLLEXPORT uint64_t unresolve_rva(uint64_t ptr);
     IL2CPP_MODLOADER_DLLEXPORT uint64_t resolve_unity_player_rva(uint64_t rva);
-}
+    IL2CPP_MODLOADER_DLLEXPORT void modify_memory(uint64_t address, uint64_t length, const std::function<void(uint8_t* memory)>& fn);
+}
diff --git a/projects/Randomizer/features/controls/autoaim.cpp b/projects/Randomizer/features/controls/autoaim.cpp
@@ -6,9 +6,7 @@
 #include <Modloader/app/methods/Game/Targets.h>
 #include <Modloader/app/methods/SeinBowAttack.h>
 #include <Modloader/app/methods/SeinChakramSpell.h>
-#include <Modloader/app/methods/SeinSpiritSpearSpell.h>
 #include <Modloader/app/types/IAttackable.h>
-#include <Modloader/il2cpp_helpers.h>
 #include <Modloader/interception_macros.h>
 #include <Modloader/modloader.h>
 
@@ -23,6 +21,24 @@ namespace {
     //     overwrite_attackables = false;
     // }
 
+    [[maybe_unused]]
+    auto on_injection_complete = modloader::event_bus().register_handler(ModloaderEvent::InjectionComplete, [](auto) {
+        // In vanilla, the game divides the distance to enemies by 10, making the spear autoaim heavily prefer targeting them
+        // over anything else. The DIVSS instruction lives at 0xa74431, and here we replace it with NOP instructions to
+        // disable that behavior.
+        modloader::win::memory::modify_memory(
+            modloader::win::memory::resolve_rva(0xa74431),
+            5,
+            [](auto memory) {
+                memory[0] = static_cast<uint8_t>(modloader::win::memory::Instruction::NOP);
+                memory[1] = static_cast<uint8_t>(modloader::win::memory::Instruction::NOP);
+                memory[2] = static_cast<uint8_t>(modloader::win::memory::Instruction::NOP);
+                memory[3] = static_cast<uint8_t>(modloader::win::memory::Instruction::NOP);
+                memory[4] = static_cast<uint8_t>(modloader::win::memory::Instruction::NOP);
+            }
+        );
+    });
+
     IL2CPP_INTERCEPT(SeinChakramSpell, void, UpdateCharacterState, (app::SeinChakramSpell * this_ptr)) {
         this_ptr->fields.AutoAimEnabled = core::settings::autoaim();
         // Maybe we still want this on?