- 2.4.0:
  - **Major updates**
    - New refraction channel for Standard material (including fresnel support). Refraction texture can be provided by a reflection probe or a refraction texture. [See demo here](http://www.babylonjs.com/Demos/refraction/) ([deltakosh](https://github.com/deltakosh))
    - Added support for HDR cubemaps ([sebavan](https://github.com/sebavan))
    - Support for shaders includes ([deltakosh](https://github.com/deltakosh))
    - new mesh type : `LineSystem` ([jerome](https://github.com/jbousquie))
    - SerializationHelper for complex classes using TypeScript decorators  ([deltakosh](https://github.com/deltakosh))
    - StandardMaterial now supports Parallax and Parallax Occlusion Mapping ([nockawa](https://github.com/nockawa))
    - Animations blending. See [demo here](http://www.babylonjs-playground.com/#2BLI9T#3). More [info here](NEED DOC!) ([deltakosh](https://github.com/deltakosh))
    - New debuger tool: SkeletonViewer. See [demo here](Demo available here: http://www.babylonjs-playground.com/#1BZJVJ#8) (Adam & [deltakosh](https://github.com/deltakosh))
    - Added Camera Inputs Manager to manage camera inputs (mouse, touch, keyboard, gamepad, ...) in a composable way, without relying on class inheritance [gleborgne](https://github.com/gleborgne)
    - Introduced new observable system to handle events ([nockawa](https://github.com/nockawa), [deltakosh](https://github.com/deltakosh))
    - Added a new VR camera : VRDeviceOrientationArcRotateCamera [temechon](https://github.com/Temechon)
  - **Updates**
    - Added skeleton.getBoneIndexByName(boneName: string) [dad72](https://github.com/dad72)
    - Added node._children to track children hierarchy ([deltakosh](https://github.com/deltakosh))
    - Added Camera.ForceAttachControlToAlwaysPreventDefault to help embedding Babylon.js in iFrames ([deltakosh](https://github.com/deltakosh))
    - Support for Layer.alphaTest ([deltakosh](https://github.com/deltakosh))
    - New scene.pointerDownPredicate, scene.pointerMovePredicate, scene.pointerUpPredicate to define your own predicates for meshes picking selection ([deltakosh](https://github.com/deltakosh))
    - New OnPickTrigger support for spritesManager ([deltakosh](https://github.com/deltakosh))
    - New SPS method `digest()` ([jerome](https://github.com/jbousquie))    
    - New SPS property `computeBoundingBox` ([jerome](https://github.com/jbousquie))  
    - Added a new OnPickOut trigger fired when you release the pointer button outside of a mesh or sprite. ([deltakosh](https://github.com/deltakosh))
    - Added support for OnPointerOver and OnPointerOut for sprites. ([deltakosh](https://github.com/deltakosh))
  - **API doc**
    - class `SolidParticleSystem` documented
    - class `MeshBuilder` documented
  - **Bug fixes**
    - Fixed bug with ArcRotateCamera.setTarget ([deltakosh](https://github.com/deltakosh))
  - **Breaking changes**
    - `VertexData.CreateLines()` removed as `MeshBuilder.CreateLines()` now calls `MeshBuilder.CreateLineSystem()`
    - `scene.onNewXXXAdded` and `scene.onXXXRemoved' callbacks were removed and replaced by `scene.onNewXXXAddedObservable` and `scene.onXXXRemovedObservable`