There’s an interesting real-time PBR viewport for Cinema 4D, PixelBerg which is now in a stable 1.9 beta. It seems to be genuine full-scene real-time, and doesn’t need a powerful graphics-card to run. Which might make it an alternative real-time option to consider before you plunge into an iClone purchase and the Reallusion content/upgrade ecosystem.
Here’s a side-by-side render demo of Pixelberg running in real-time as the main viewport, using a HDR for lighting, alongside the turbo-charged 24-seconds final render. It seems to be genuinely What You See Is What You Get (WYSIWYG)…
Pixelberg may be especially interesting to Poser Pro 11 users, as Poser interfaces smoothly with Cinema 4D via Smith Micro’s PoserFusion plugin. Only the Pro version has the PoserFusion plugins which seamlessly and quickly take your Poser scene to Vue, Cinema 4D etc.
Nice price for PixelBerg, too. $1!
“PixelBerg is available to buy and download now at Pay What You Want Price. (minimum $1)”.
Cinema 4D itself is sadly a lot more expensive, with the cheapest version being $995. But depending on your ‘destination configuration’ for iClone, that may be price-comparable with iClone Pro + extras (provided that you can do things like roll your own figure-animations, or can bring them in from Poser). If you’re in education, note that Cinema 4D has an 18-month student and teacher license which comes in two flavours: free (full featured, but no plugins will run) or £140 (can run plugins in it). Running PixelBerg would require the £140 Educational version.
Update: I hear that Cinema 4D also supports the Indigo renderer, part of which provides a GPU-powered large supposedly real-time preview window. But it costs a hefty 200 Euros, and according for their forums the “real-time” interactive preview window is still limited and buggy at December 2017. The new Cinema 4D R19 also reportedly has a new fast native viewport built-in.