1 files changed, 87 insertions, 0 deletions
diff --git a/RenderScript/include/ClassMethodBinding.h b/RenderScript/include/ClassMethodBinding.h
new file mode 100644
index 0000000..90c4259
--- /dev/null
+++ b/RenderScript/include/ClassMethodBinding.h
@@ -0,0 +1,87 @@
+/*     Copyright 2015 Egor Yusov
+ *  
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF ANY PROPRIETARY RIGHTS.
+ *
+ *  In no event and under no legal theory, whether in tort (including negligence), 
+ *  contract, or otherwise, unless required by applicable law (such as deliberate 
+ *  and grossly negligent acts) or agreed to in writing, shall any Contributor be
+ *  liable for any damages, including any direct, indirect, special, incidental, 
+ *  or consequential damages of any character arising as a result of this License or 
+ *  out of the use or inability to use the software (including but not limited to damages 
+ *  for loss of goodwill, work stoppage, computer failure or malfunction, or any and 
+ *  all other commercial damages or losses), even if such Contributor has been advised 
+ *  of the possibility of such damages.
+ */
+
+#pragma once
+
+namespace Diligent
+{
+    template<typename OwnerClassType>
+    class ClassMethodCaller
+    {
+    public:
+        typedef int(OwnerClassType::*MemberFunctionType)(lua_State *LuaState);
+
+        ClassMethodCaller( OwnerClassType *pOwner,
+                            lua_State *L,
+                            const Char *LuaTableName,
+                            const Char *LuaFunctionName,
+                            MemberFunctionType MemberFunction) :
+            m_MemberFunction( MemberFunction )
+        {
+            INIT_LUA_STACK_TRACKING( L );
+
+            lua_getglobal( L, LuaTableName );       // -0 | +1 -> +1
+            if( lua_type( L, -1 ) == LUA_TNIL )
+            {
+                // Global name is not found, try to find metatable with that name
+                // Pop nil from the stack
+                lua_pop( L, 1 );                        // -1 | +0 -> -1
+                luaL_getmetatable( L, LuaTableName );   // -0 | +1 -> +1
+            }
+            CheckType( L, -1, LUA_TTABLE );
+            lua_pushstring( L, LuaFunctionName );   // -0 | +1 -> +1
+            lua_pushlightuserdata( L, pOwner );     // -0 | +1 -> +1
+            lua_pushlightuserdata( L, this );       // -0 | +1 -> +1
+            lua_pushcclosure( L, LuaEntry, 2 );     // -2 | +0 -> -2
+            lua_settable( L, -3 );                  // -1 | +0 -> -1
+            // Pop table
+            lua_pop( L, 1 );                        // -1 | +0 -> -1
+
+            CHECK_LUA_STACK_HEIGHT();
+        };
+
+    private:
+        MemberFunctionType m_MemberFunction;
+
+        static int LuaEntry( lua_State *L )
+        {
+            auto pOwner = static_cast<OwnerClassType*>(lua_touserdata( L, lua_upvalueindex( 1 ) ));
+            VERIFY( pOwner, "Owner pointer is null" );
+
+            auto pThis = static_cast<ClassMethodCaller*>(lua_touserdata( L, lua_upvalueindex( 2 ) ));
+            VERIFY( pThis, "This pointer is null" );
+
+            if( pOwner && pThis )
+            {
+                auto MemberFunction = pThis->m_MemberFunction;
+
+                // A C function returns an integer with the number of values it is returning in Lua. 
+                // Therefore, the function does not need to clear the stack before pushing its results. 
+                // After it returns, Lua automatically removes whatever is in the stack below the results.
+                return (pOwner->*MemberFunction)(L);
+            }
+            else
+                return 0;
+        }
+    };
+}