Render Brian Paul's classic OpenGL "gears" demo with TinyGL on a NuttX
framebuffer device. TinyGL draws each frame into its own ZBuffer, which
is then copied to the mmap()ed framebuffer (plus FBIO_UPDATE when
CONFIG_FB_UPDATE is enabled), so partially drawn frames are never shown.
The frame rate is printed every five seconds.
Usage: tinygl [frames] [fbdev]
Tested on sim:tinygl (640x480, 32 bpp): about 1400 FPS with
CONFIG_DEBUG_FULLOPT on an x86_64 host, with both make and CMake.
Assisted-By: Claude Opus 5.5 (1M context)
Signed-off-by: Alan Carvalho de Assis <acassis@gmail.com>
