I've added support (using the framebuffer copy method) into the Engine. For right now I plan on maintaining it as a separate fork.
Github repo: xgundam05/Urho3D
The additional engine parameters are as follows:
EnableTFT : Boolean, default=false. Enables TFT Display in engine initialization
TFTSourceBuffer : Integer, default=0. Source display to copy from. Raspbian Jessie sets TV (HDMI/RCA) out as 0
TFTFramebuffer : String, default="/dev/fb1". Framebuffer location of the TFT display. FBTFT DT Overlays in Rasbian Jessie default to "/dev/fb1"
* Add detection, reassignment and restoring of console framebuffer (currently this is handled via bash script)
* Add detection, initialization and restoring of TV Out settings (available via VideoCore libraries, currently handled via boot/config.txt settings)