LuxCoreRender, (formerly known as LuxRender), is a physically based, unbiased rendering engine. It is free, and its site claims it will ever be. This standalone render engine could be used with different 3d programs. A Blender (https://www.blender.org) add on makes it immediately available from within Blender. This makes LuxCore Render an interesting alternative render engine for Mac users, since it could fill the gap left by Cycles (the most accurate Blender internal rendering engine) which is, as for now, incapable of GPU rendering on Macs. Being based on OpenCL, LuxCoreRender can take advantage of GPU rendering , and could be also set up to use Cycles materials. Did I mention it's free?

LuxRender is available for free, it is Open Source and the fact that it is Physically Based, It's ability to use OpenCL to speed up rendering by using all the available OpenCL compatible hardware and even over the network, is great. Due to its PBR nature the end results have a very photographic look. The development of luxCore looks very promising and has significant speed improvements over the past releases. Several integration plugins are available for LuxRender, E.g. Blender, 3ds Max, Maya, Cinema 4d and Sketchup to name a few. My experience has been using it with blender and the integration is flawless and allows for a 1 click cycles scene convert. The 1.6 release with collapsible menu saves a lot of screen real estate. The new biased path rendering mode is very fast with OpenCL. and the new Halt Conditions menu allows for autostopping a render at an estimated noise level.