Enable Mulit-viewports

Getting-Started.md

@@ -10,6 +10,7 @@
 - [Example: If you are using SDL2 + OpenGL/WebGL](#example-if-you-are-using-sdl2--openglwebgl)
 - [Example: If you are using SDL2 + Vulkan](#example-if-you-are-using-sdl2--vulkan)
 - [Using another combination of backends?](#using-another-combination-of-backends)
+- [Additional code to enable Multi-viewports mode](#additional-code-to-enable-multi-viewports-mode)
 
 ## Preamble 
 
@@ -408,4 +409,17 @@ That should be all!
 ## Using another combination of backends?
 
 The various examples above should reflect integration with a majority of backends, so you can follow the same logic.
-Some backends require more information from you (e.g. in particular Vulkan and DirectX12 rendering backends). When in doubt, refer to the corresponding [examples](https://github.com/ocornut/imgui/tree/master/examples) application.
+Some backends require more information from you (e.g. in particular Vulkan and DirectX12 rendering backends). When in doubt, refer to the corresponding [examples](https://github.com/ocornut/imgui/tree/master/examples) application.
+
+## Additional code to enable Multi-viewports mode
+
+To use the [Multi-viewports](https://github.com/ocornut/imgui/wiki/Multi-Viewports) feature, pull the `docking` branch and enable the configuration flag:
+```cpp
+io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable; 
+```
+At the end of your render loop, generally after rendering your main viewport but before presenting/swapping it:
+```cpp
+// Update and Render additional Platform Windows
+ImGui::UpdatePlatformWindows();
+ImGui::RenderPlatformWindowsDefault();
+```