Side Effects Software has released Houdini 15, with a slate of new tools including onion-skinning, new shader builders, ragdoll crowd simulation, and Houdini Engine 2.0. We've picked out some highlights below, but the following promo video will give you a better sense of how the new features work.

Houdini's Mantra renderer has been updated with checkpointing and render-view feedback. New shader-building features include a new shader library, a rebuilt Shader FX menu, layered materials, and a cartoon shader. And support for RenderMan 20 is built in via RenderMan for Houdini, which supports the RIS framework, geometric area lights, and Houdini's shader suite.

In the modeling interface, added features include edge sliding, various "tweak edit" functions, and new tools including PolyBridge, PolyExtrude, and PolyExpand 2D. New retopology tools allow low-res geometery to be built by drawing on top of high-res geometry. 

Houdini 15's crowd tools now offer ragdoll dynamics, limb detachment and fuzzy logic. New tools allow target locations to be specified. And VFX workflow has been enhanced with adaptive position-based dynamics (PBD) for focusing grain simulation on collision areas and viscous-fluid tools including Lava, Melt Object, and Emit Steam.