Expose Noesis visual coordinate conversion and hit testing to Lua

BG3Extender/GameDefinitions/PropertyMaps/UI.inl

@@ -121,6 +121,9 @@ INHERIT(Noesis::DependencyObject)
 P_FREE_GETTER(VisualParent, Noesis::VisualHelpers::GetVisualParent)
 P_FREE_GETTER(VisualChildrenCount, Noesis::VisualHelpers::GetVisualChildrenCount)
 P_FUN(VisualChild, Noesis::VisualHelpers::GetVisualChild)
+P_FUN(PointFromScreen, Noesis::VisualHelpers::PointFromScreen)
+P_FUN(PointToScreen, Noesis::VisualHelpers::PointToScreen)
+P_FUN(HitTest, Noesis::VisualHelpers::HitTest)
 END_CLS()
 
 

BG3Extender/GameDefinitions/Symbols.h

@@ -154,6 +154,9 @@ namespace bg3se
         void* Noesis__GUI__LoadXaml{ nullptr };
         void* Noesis__Visual__AddVisualChild{ nullptr };
         void* Noesis__Visual__RemoveVisualChild{ nullptr };
+        void* Noesis__Visual__PointFromScreen{ nullptr };
+        void* Noesis__Visual__PointToScreen{ nullptr };
+        void* Noesis__VisualTreeHelper__HitTest{ nullptr };
 
         GlobalSwitches** ls__GlobalSwitches{ nullptr };
 

BG3Extender/GameDefinitions/UI.h

@@ -16,6 +16,7 @@
 #include <NsGui/ObservableCollection.h>
 #include <NsGui/UIElementCollection.h>
 #include <NsGui/ContentControl.h>
+#include <NsGui/VisualTreeHelper.h>
 
 BEGIN_BARE_NS(Noesis)
 
@@ -29,6 +30,8 @@ struct GridLengthHelper
 };
 
 using LoadXamlProc = Ptr<BaseComponent>* (Ptr<BaseComponent>& ret, char const* path);
+using VisualPointConversionProc = Point (Visual::*)(Point const& point) const;
+using VisualTreeHelperHitTestProc = HitTestResult (*)(Visual* visual, Point const& point);
 
 struct SymbolManagerInternals
 {
@@ -213,6 +216,9 @@ struct VisualHelpers
     static Visual* GetVisualParent(Visual const* o);
     static uint32_t GetVisualChildrenCount(lua_State* L, Visual const* o);
     static Visual* GetVisualChild(Visual const* o, uint32_t index);
+    static Point PointFromScreen(lua_State* L, Visual const* o, Point const& point);
+    static Point PointToScreen(lua_State* L, Visual const* o, Point const& point);
+    static Visual* HitTest(lua_State* L, Visual* o, Point const& point);
 };
 
 struct UIElementDataHelpers

BG3Extender/GameHooks/BinaryMappings.xml

@@ -1010,6 +1010,42 @@
       <Target Type="Indirect" Offset="@ref2" Symbol="Noesis__Visual__AddVisualChild" />
     </Mapping>
 
+    <Mapping Name="Noesis::Visual::PointToScreen" AllowFail="true">
+      @target 48 89 5c 24 18 // mov     [rsp+18h], rbx
+      57 // push    rdi
+      b8 00 01 00 00 // mov     eax, 100h
+      e8 ?? ?? ?? ?? // call    __alloca_probe
+      48 2b e0 // sub     rsp, rax
+      0f 29 b4 24 f0 00 00 00 // movaps  [rsp+0F0h], xmm6
+      0f 29 bc 24 e0 00 00 00 // movaps  [rsp+0E0h], xmm7
+      48 8b 05 ?? ?? ?? ?? // mov     rax, [__security_cookie]
+      48 33 c4 // xor     rax, rsp
+      48 89 84 24 d0 00 00 00 // mov     [rsp+0D0h], rax
+      f3 41 0f 10 30 // movss   xmm6, dword ptr [r8]
+      48 8b fa // mov     rdi, rdx; Point return buffer
+      f3 41 0f 10 78 04 // movss   xmm7, dword ptr [r8+4]
+      48 8d 54 24 60 // lea     rdx, [rsp+60h]
+      48 8b d9 // mov     rbx, rcx; Visual this
+      <Target Type="Absolute" Offset="@target"
+        Symbol="Noesis__Visual__PointToScreen" />
+    </Mapping>
+
+    <Mapping Name="Noesis::VisualTreeHelper::HitTest" AllowFail="true">
+      4c 8d 47 18 // lea     r8, [rdi+18h]; screen Point
+      48 8d 54 24 20 // lea     rdx, [rsp+20h]; Point return buffer
+      @ref0 e8 ?? ?? ?? ?? // call    Noesis::Visual::PointFromScreen
+      4c 8b c0 // mov     r8, rax; local Point
+      48 8b 97 a8 00 00 00 // mov     rdx, [rdi+0A8h]; Visual
+      48 8d 4c 24 28 // lea     rcx, [rsp+28h]; HitTestResult return buffer
+      @ref1 e8 ?? ?? ?? ?? // call    Noesis::VisualTreeHelper::HitTest
+      48 83 38 00 // cmp     qword ptr [rax], 0; result.visualHit
+      0f 85 ?? ?? ?? ?? // jnz
+      <Target Type="Indirect" Offset="@ref0"
+        Symbol="Noesis__Visual__PointFromScreen" />
+      <Target Type="Indirect" Offset="@ref1"
+        Symbol="Noesis__VisualTreeHelper__HitTest" />
+    </Mapping>
+
     <!-- Sigs: exposed as "IsReachable" -->
     <Mapping Name="eoc::AiGrid::FindPath">
       48 8b 83 a8 01 00 00 // mov     rax, [rbx+1A8h]

BG3Extender/GameHooks/DataLibrariesBG3Game.cpp

@@ -218,6 +218,9 @@ namespace bg3se
         SYM_OFF(Noesis__GUI__LoadXaml);
         SYM_OFF(Noesis__Visual__AddVisualChild);
         SYM_OFF(Noesis__Visual__RemoveVisualChild);
+        SYM_OFF(Noesis__Visual__PointFromScreen);
+        SYM_OFF(Noesis__Visual__PointToScreen);
+        SYM_OFF(Noesis__VisualTreeHelper__HitTest);
 
         SYM_OFF(AppInstance);
 

BG3Extender/Lua/Libs/ClientUI/NsHelpers.inl

@@ -714,6 +714,73 @@ Visual* VisualHelpers::GetVisualChild(Visual const* o, uint32_t index)
     }
 }
 
+namespace
+{
+    void EnsureVisualClientThread(lua_State* L, char const* functionName)
+    {
+        auto state = lua::State::FromLua(L);
+        if (state == nullptr
+            || !state->IsClient()
+            || GetCurrentContextType() != ContextType::Client) {
+            luaL_error(L, "%s() can only be called from Client Lua", functionName);
+            return;
+        }
+
+        if (state->GetExtensionState().GetOwningThread() != GetCurrentThreadId()) {
+            luaL_error(L, "%s() can only be called on the Client owning thread", functionName);
+        }
+    }
+
+    void* RequireNoesisMapping(lua_State* L, void* address, char const* symbol)
+    {
+        if (address == nullptr) {
+            luaL_error(L, "%s mapping is unavailable for the current game version", symbol);
+            return nullptr;
+        }
+
+        return address;
+    }
+
+    Point InvokeVisualPointConversion(Visual const* visual, Point const& point, void* address)
+    {
+        // Visual has multiple inheritance in its ancestry, so a MSVC member-function
+        // pointer may be wider than a code pointer. Zero-initialize its adjustment
+        // fields and copy only the mapped function address into its code slot.
+        VisualPointConversionProc proc{};
+        static_assert(sizeof(proc) >= sizeof(address));
+        memcpy(&proc, &address, sizeof(address));
+        return (visual->*proc)(point);
+    }
+}
+
+Point VisualHelpers::PointFromScreen(lua_State* L, Visual const* o, Point const& point)
+{
+    EnsureVisualClientThread(L, "PointFromScreen");
+    auto address = RequireNoesisMapping(L,
+        GetStaticSymbols().Noesis__Visual__PointFromScreen,
+        "Noesis::Visual::PointFromScreen");
+    return InvokeVisualPointConversion(o, point, address);
+}
+
+Point VisualHelpers::PointToScreen(lua_State* L, Visual const* o, Point const& point)
+{
+    EnsureVisualClientThread(L, "PointToScreen");
+    auto address = RequireNoesisMapping(L,
+        GetStaticSymbols().Noesis__Visual__PointToScreen,
+        "Noesis::Visual::PointToScreen");
+    return InvokeVisualPointConversion(o, point, address);
+}
+
+Visual* VisualHelpers::HitTest(lua_State* L, Visual* o, Point const& point)
+{
+    EnsureVisualClientThread(L, "HitTest");
+    auto address = RequireNoesisMapping(L,
+        GetStaticSymbols().Noesis__VisualTreeHelper__HitTest,
+        "Noesis::VisualTreeHelper::HitTest");
+    auto proc = reinterpret_cast<VisualTreeHelperHitTestProc>(address);
+    return proc(o, point).visualHit;
+}
+
 RoutedEvent* UIElementDataHelpers::GetEvent(UIElementData const* o, Symbol evt)
 {
     auto it = o->mEvents.Find(evt);

BG3Extender/Lua/LuaSerializers.h

@@ -115,6 +115,14 @@ namespace bg3se::lua
     inline LuaSerializer& serialize(LuaSerializer& s, STDWString& v) { return s.Visit(v); }
     inline LuaSerializer& serialize(LuaSerializer& s, StringView& v) { return s.Visit(v); }
     inline LuaSerializer& serialize(LuaSerializer& s, Noesis::Symbol& v) { return s.Visit(v); }
+    inline LuaSerializer& serialize(LuaSerializer& s, Noesis::Point& v)
+    {
+        s.BeginObject();
+        s.VisitProperty("X", v.x);
+        s.VisitProperty("Y", v.y);
+        s.EndObject();
+        return s;
+    }
     inline LuaSerializer& serialize(LuaSerializer& s, ImguiHandle& v) { return s.Visit(v); }
     inline LuaSerializer& serialize(LuaSerializer& s, Path& v) { return s.Visit(v); }
     inline LuaSerializer& serialize(LuaSerializer& s, Guid& v) { return s.Visit(v); }