Examples: Refactored directx9_example to be eaasier to copy & paste into user application.

examples/directx9_example/imgui_impl_dx9.h

@@ -0,0 +1,16 @@
+// ImGui Win32 + DirectX9 binding
+// https://github.com/ocornut/imgui
+
+struct IDirect3DDevice9;
+
+bool        ImGui_ImplDX9_Init(void* hwnd, IDirect3DDevice9* device, bool install_callbacks);
+void        ImGui_ImplDX9_InitFontsTexture();
+void        ImGui_ImplDX9_Shutdown();
+void        ImGui_ImplDX9_NewFrame();
+
+// Handler for Win32 messages, update mouse/keyboard data.
+// You may or not need this for your implementation, but it can serve as reference for handling inputs.
+// Commented out to avoid dragging dependencies on <windows.h> types. You can copy the extern declaration in your code.
+/*
+extern LRESULT   ImGui_ImplDX9_WndProcHandler(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);
+*/