Add README.md

README.md

+MR Designer is a Mixed Reality applications for creating 3D models using a Valve Index.
+
+# Requirements
+- Valve Index, [Steam VR](https://www.steamvr.com "Steam VR")
+- [OpenXR SteamVR Passthrough API Layer](https://github.com/Rectus/openxr-steamvr-passthrough/releases)
+- [Unity 2021.3.5f1](https://unity.com/releases/editor/whats-new/2021.3.5 "Unity 2021.3.5f1")
+
+# Usage
+- [configure the Passthrough API](https://github.com/Rectus/openxr-steamvr-passthrough#usage "configure the Passthrough API")
+- open the unity project with the unity editor and click play
+- create a 3D Model in VR
+	- first add 4 starting nodes
+	- then select your desired mode on the menu
+		- the menu is attached to your left controller
+		- buttons are pressed with the right controller
+	- apply the actions to the model using the \"trigger\" button
+		- connect requires you to hold the button until 3 or 4 nodes are marked
+		- adding or deleting is applied after release
+		- a preview node helps selecting triangles for deletion
+	- the reset button requires continuously pressing for 1 seconds
+- Export the model using the FBX exporter
+	- select the \"3D-Model\" GameObject
+	- delete all childobjects
+	- rightclick the  \"3D-Model\" and select \"Export to FBX...\"
+	- click \"Export\"
+	
+# Demo video
+
+[![MR 3D-Model Designer](http://img.youtube.com/vi/MA0ZtmunfoY/0.jpg)](http://www.youtube.com/watch?v=MA0ZtmunfoY "MR 3D-Model Designer")