fix readme

README.md

@@ -1,16 +1,28 @@
 # DotRecast
+C# Port of Recast & Detour navigation mesh toolset
+
 ![DotRecast of a navmesh baked with the sample program](/src/DotRecast.Recast.Demo/screenshot.png?raw=true)
 
-DotRecast is a port of recast4j(https://github.com/ppiastucki/recast4j) to C# and has been built to target netstandard2.1 to work with both Unity3D and pure C#.
+## Recast
 
-If you're using Unity3D, the following projects have been modified to build with netstandard2.1:
+Recast is state of the art navigation mesh construction toolset for games.
+
+Recast is...
+* 🤖 **Automatic** - throw any level geometry at it and you will get a robust navmesh out
+* 🏎️ **Fast** - swift turnaround times for level designers
+* 🧘 **Flexible** - easily customize the navmesh generation and runtime navigation systems to suit your specific game's needs.
+
+Recast constructs a navmesh through a multi-step rasterization process:
+
+1. First Recast voxelizes the input triangle mesh by rasterizing the triangles into a multi-layer heightfield.
+2. Voxels in areas where the character would not be able to move are removed by applying simple voxel data filters.
+3. The walkable areas described by the voxel grid are then divided into sets of 2D polygonal regions.
+4. The navigation polygons are generated by triangulating and stiching together the generated 2d plygonal regions.
+
+## Detour
+
+Recast is accompanied by Detour, a path-finding and spatial reasoning toolkit. You can use any navigation mesh with Detour, but of course the data generated with Recast fits perfectly.
+
+Detour offers a simple static navmesh data representation which is suitable for many simple cases.  It also provides a tiled navigation mesh representation, which allows you to stream of navigation data in and out as the player progresses through the world and regenerate sections of the navmesh data as the world changes.
 
-- DotRecast.Core
-- DotRecast.Recast
-- DotRecast.Detour
-- DotRecast.Detour.Crowd
-- DotRecast.Detour.Dynamic
-- DotRecast.Detour.Extras
-- DotRecast.Detour.TileCache
 
- Please feel free to copy and use these projects in Unity3D. We plan to continue improving them as time goes on.