diff --git a/README.md b/README.md
index aeade11..35bd2ff 100644
--- a/README.md
+++ b/README.md
@@ -31,7 +31,9 @@ Notes:
 * you will need LuaJIT (https://github.com/LuaJIT/LuaJIT.git better 2.1 branch) or precompiled for linux/macOS/windows in https://luapower.com/luajit/download
 * you can use also a C++ compiler for doing preprocessing: gcc (In windows MinGW-W64-builds for example), clang or cl (MSVC) or not use a compiler (experimental nocompiler option) at all. (this repo was done with gcc)
 * update `imgui` folder to the version you desire.
-* edit `generator/generator.bat` on windows, or `generator/generator.sh` on linux, to choose between gcc, clang, cl or nocompiler. Run it with gcc, clang or cl and LuaJIT on your PATH.
+* edit `generator/generator.bat` on windows, or `generator/generator.sh` on linux, to choose between gcc, clang, cl or nocompiler and to choose desired implementations. 
+* edit config_generator.lua for adding includes needed by your chosen implementations.
+* Run generator.bat or generator.sh with gcc, clang or cl and LuaJIT on your PATH.
 * as a result some files are generated: `cimgui.cpp` and `cimgui.h` for compiling and some lua/json files with information about the binding: `definitions.json` with function info, `structs_and_enums.json` with struct and enum info, `impl_definitions.json` with functions from the implementations info. 
 
 # generate binding
diff --git a/generator/config_generator.lua b/generator/config_generator.lua
new file mode 100644
index 0000000..1a15d59
--- /dev/null
+++ b/generator/config_generator.lua
@@ -0,0 +1,3 @@
+return {
+	vulkan = {[[C:\VulkanSDK\1.1.130.0\Include]]}
+}
\ No newline at end of file
diff --git a/generator/generator.lua b/generator/generator.lua
index 6d60af0..bee6598 100644
--- a/generator/generator.lua
+++ b/generator/generator.lua
@@ -189,6 +189,13 @@ end
 
 
 --------------------------------functions for C generation
+--load parser module
+local cpp2ffi = require"cpp2ffi"
+local read_data = cpp2ffi.read_data
+local save_data = cpp2ffi.save_data
+local copyfile = cpp2ffi.copyfile
+local serializeTableF = cpp2ffi.serializeTableF
+
 local function func_header_impl_generate(FP)
 
     local outtab = {}
@@ -197,11 +204,19 @@ local function func_header_impl_generate(FP)
         if t.cimguiname then
             local cimf = FP.defsT[t.cimguiname]
             local def = cimf[t.signature]
-            if def.ret then --not constructor
-                local addcoment = def.comment or ""
+			local addcoment = def.comment or ""
+			if def.constructor then
+				-- it happens with vulkan impl but constructor ImGui_ImplVulkanH_Window is not needed
+			    --assert(def.stname ~= "","constructor without struct")
+                --table.insert(outtab,"CIMGUI_API "..def.stname.."* "..def.ov_cimguiname ..(empty and "(void)" or --def.args)..";"..addcoment.."\n")
+            elseif def.destructor then
+                --table.insert(outtab,"CIMGUI_API void "..def.ov_cimguiname..def.args..";"..addcoment.."\n")
+			else
+                
                 if def.stname == "" then --ImGui namespace or top level
                     table.insert(outtab,"CIMGUI_API".." "..def.ret.." "..def.ov_cimguiname..def.args..";"..addcoment.."\n")
                 else
+					cpp2ffi.prtable(def)
                     error("class function in implementations")
                 end
             end
@@ -424,12 +439,7 @@ local function DefsByStruct(FP)
 end  
 
 
---load parser module
-local cpp2ffi = require"cpp2ffi"
-local read_data = cpp2ffi.read_data
-local save_data = cpp2ffi.save_data
-local copyfile = cpp2ffi.copyfile
-local serializeTableF = cpp2ffi.serializeTableF
+
 
 ----------custom ImVector templates
 local function generate_templates(code,templates)
@@ -710,14 +720,22 @@ local parser2
 if #implementations > 0 then
 
     parser2 = cpp2ffi.Parser()
-
+	
+	local config = require"config_generator"
     
     for i,impl in ipairs(implementations) do
         local source = [[../imgui/examples/imgui_impl_]].. impl .. ".h "
         local locati = [[imgui_impl_]].. impl
         local pipe,err
+		local extra_includes = ""
+		local include_cmd = COMPILER=="cl" and [[ /I ]] or [[ -I ]]
+		if config[impl] then
+			for j,inc in ipairs(config[impl]) do
+				extra_includes = extra_includes .. include_cmd .. inc .. " "
+			end
+		end
         if HAVE_COMPILER then
-            pipe,err = io.popen(CPRE..source,"r")
+            pipe,err = io.popen(CPRE..extra_includes..source,"r")
         else
             pipe,err = io.open(source,"r")
         end