Optimize polar chart radius calculation a bit....
Optimize polar chart radius calculation a bit.
Current algorithm still results in an occasional extra unneeded
iteration, as it uses only crude approximation for radius reduction.
However, any speedup gained by accurately calculating needed
reduction would be very minor compared to approximations used,
so it doesn't seem worth the effort to figure out the complex math.
Change-Id: If670a1b058a85cd0305b93f62e6388b463bafd0d
Reviewed-by: Tomi Korpipää <tomi.korpipaa@digia.com>