CGAL users discussion list

well, I really answered too quickly... (I mixed up Circular_arc_2 and 
Circular_arc_point_2)
Again, the problem comes from the fact that we forgot the case 
Line_2/Circle_2 in functor Intersect_2 that gives the interface for 
users, so, waiting for the fix, let's try to find a reasonable 
workaround. I have a few proposals:

1- Is it possible for you to clip your Line_2 into a Segment_2, just for 
computing the intersection?
If you can do this, then the simplest workaround is probably to use
CircularKernel::Intersect_2 for a Line_arc_2 and a Circle_2,
because Line_arc_2 can be constructed from Segment_2.

2- The intersection between Line_2 and Circle_2 is in fact coded 
internally in
include/CGAL/Circular_kernel_2/internal_functions_on_line_2.h
So, if you want to hack a little bit, you can probably use it.

3- You can also probably first construct a Circular_arc_2 from the 
circle and two identical lines equal to your line, I guess it should 
work, then ask for the endpoints of the circular arc.

I hope one of these workarounds can help.

陳 柏宏 wrote:
> hi,
> thanks for replying. i am still not sure how to use it
> to find the intersection of a circle and line though..