Is it a render, or real-time OpenGL?
Release 19 adds support for Screen-Space Reflections and OpenGL Depth-Of-Field in addition to Screen Space Ambient Occlusion and Tessellation. The OpenGL view looks so good you can use it to output preview renders directly for client approval using the new native MP4 support.
LOD (Level Of Detail)
Maximize viewport or render speed, create new types of animations or prepare optimized game assets with the new LOD object. You can simplify objects and hierarchies automatically based on screen size, camera distance and other factors. An intuitive new interface element makes it easy to define and manage LOD settings, and your levels of details export via FBX for use in popular game engines.
New Media Core
As part of our core modernization effort, Cinema 4D’s support for image, video and audio formats has been completely rewritten for increased speed and memory efficiency. Cinema 4D now natively supports MP4 without QuickTime, so it’s easier than ever to deliver a preview render, incorporate video as textures or motion track some footage. All import and export formats are more robust and feature packed than ever before.