Re: Gets vertical skylines from grob stencils (issue 5626052)

[address@hidden]

On Feb 16, 2012, at 9:31 PM, Joe Neeman wrote:

On Thu, Feb 16, 2012 at 3:14 AM, address@hidden <address@hidden> wrote:

On Feb 16, 2012, at 11:40 AM, address@hidden wrote:

>
> The buildings are in increasing order, so this should work:
>
> Real last_end = -infinity_f;
> for (...)
>  {
>    if (i->y_intercept_ > -infinity_f)
>      return last_end;
>    last_end = i->end_;
>  }
> return infinity_f;
>

Hey,

I know this is a lame question, but how would one write the reverse iterator.  I tried using reverse_iterator and g++ barfs, and I can't use the same syntax one would use in a for loop w/ a vector.

That's a bit hard to say without knowing what you tried... did you use rbegin() and rend()? 

Yup - I more or less copied the example from cplusplus.com.  As an experiment, try writing a reverse iterator in that file to the tune of:

  for (list<Building>::reverse_iterator i = buildings_.rbegin (); i != buildings_.rend (); ++i)

Anywhere in a function.  You should see a compiler error.

I fixed it, though, by reversing a copy of the list and iterating forward through it.

Cheers,

MS