Merge pull request #65 from jbikker/jbikker-patch-1

Update README.md

README.md

@@ -70,16 +70,34 @@ The **performance measurement tool** can be compiled with:
 
 # Version 1.1.1
 
-Version 1.1.x introduces a <ins>change to the API</ins>. The single BVH class with multiple layouts has been replaced with a BVH class per layout. Conversion now happens with a ````ConvertFrom```` method in each of those, or directly via the constructor. Example:
+Version 1.1.1 introduces a <ins>change to the API</ins>. The single BVH class with multiple layouts has been replaced with a BVH class per layout. You can simply instantiate the desired layout; conversion (and data ownership) is then handled properly by the library. Examples:
 
 ````
 BVH bvh;
 bvh.Build( (bvhvec4*)myTriData, triangleCount );
-BVH_SoA bvh2( bvh ); // convert from BVH to BVH_SoA
 bvh.Intersect( ray );
-bvh2.Intersect( ray );
 ````
 
+````
+BVH4_CPU bvh;
+bvh.Build( (bvhvec4*)myTriData, triangleCount );
+bvh.Intersect( ray );
+````
+
+If you wish to use a specific builder (such as the spatial splits builder) or if you need to do custom operations on the BVH, such as post-build optimizing, you can still do the conversions manually. Example:
+
+````
+BVH bvh;
+bvh.Build( (bvhvec4*)myTriData, triangleCount );
+BVH_Verbose tmp;
+tmp.ConvertFrom( bvh );
+tmp.Optimize( 100000 );
+bvh.ConvertFrom( tmp );
+printf( "Optimized BVH SAH cost: %f\n", bvh.SAHCost() );
+````
+
+Note that in this case, data ownership and lifetime must be managed carefully. Specifically, layouts converted from other layouts use data from the original, so both must be kept alive.
+
 This version of the library includes the following functionality:
 * Binned SAH BVH builder
 * Fast binned SAH BVH builder using AVX intrinsics
@@ -96,6 +114,7 @@ This version of the library includes the following functionality:
 * Support for WASM / EMSCRIPTEN, g++, clang, Visual Studio
 * Optional user-defined memory allocation, by [Thierry Cantenot](https://github.com/tcantenot)
 * Vertex array can now have a custom stride, by [David Peicho](https://github.com/DavidPeicho)
+* Clear data ownership and intuitive management via the new and simplified API, with lots of help from David Peicho
 * You can now also BYOVT ('bring your own vector types'), thanks [Tijmen Verhoef](https://github.com/nemjit001)
 * 'SpeedTest' tool that times and validates all (well, most) traversal kernels.