stencil-integrate.cc: root out "slopes"

stencil-integrate.cc: root out "slopes"

They are quite unsuitable for the computational geometry performed here.
Their use rendered the code inefficient, obtuse, and unreliable.

Contains several other fixes like removing duplicate calculations and
wrong values.  The C++ <complex> module is no longer used.  It had only
been used for calculating sin and cos in an obscure manner.


Also contains commit:

Robustify Offset::direction and Offset::length

[dak, 2015-06-29 23:26:06]

Add forgotten radius for elliptical sweeps

[lemzwerg, 2015-06-30 04:39:54]

LGTM

https://codereview.appspot.com/246590043/diff/20001/lily/stencil-integral.cc
File lily/stencil-integral.cc (right):

https://codereview.appspot.com/246590043/diff/20001/lily/stencil-integral.cc#...
lily/stencil-integral.cc:62: void create_path_cap (vector<Box> &boxes,
vector<Drul_array<Offset> > &buildings, PangoMatrix trans, Offset pt, Real rad,
Offset dir);
80 characters per line, please...

https://codereview.appspot.com/246590043/diff/20001/lily/stencil-integral.cc#...
lily/stencil-integral.cc:363: create_path_cap (vector<Box> &boxes,
vector<Drul_array<Offset> > &buildings, PangoMatrix trans, Offset pt, Real rad,
Offset dir)
ditto

[dak, 2015-06-30 05:49:27]

https://codereview.appspot.com/246590043/diff/20001/lily/stencil-integral.cc
File lily/stencil-integral.cc (right):

https://codereview.appspot.com/246590043/diff/20001/lily/stencil-integral.cc#...
lily/stencil-integral.cc:62: void create_path_cap (vector<Box> &boxes,
vector<Drul_array<Offset> > &buildings, PangoMatrix trans, Offset pt, Real rad,
Offset dir);
On 2015/06/30 04:39:54, lemzwerg wrote:
> 80 characters per line, please...

Hey, it's shorter than the original.  Will do, but won't upload another review
just for this and similar change below alone.

(Time passes)

I changed about 2 dozen other lines not written by me until I got tired of it. 
I mean, how are you going to stay at 80 characters per line when naming
functions with 7 arguments
Grob::maybe_pure_internal_simple_skylines_from_extents ?  You'll need to line up
every argument on its own in the 70th column and not be able to put the function
call in a loop.

I'll commit what I've done so far, but won't clutter this review with this sort
of prettification.

[lemzwerg, 2015-06-30 05:55:51]

Oh, I haven't meant that you should reformat everything but just the code you
are actually modifying!  But thanks anyway.

For long names I suggest a formatting like this

  Grob::maybe_pure_internal_simple_skylines_from_extents(
    foo arg1,
    bar arg2,
    ...)

to avoid exactly the problem you mention.  On the other hand, such long function
names are overly descriptive IMHO.  I think they don't really increase
readability of the code...

[dak, 2015-06-30 06:00:56]

On 2015/06/30 05:55:51, lemzwerg wrote:
> Oh, I haven't meant that you should reformat everything but just the code you
> are actually modifying!  But thanks anyway.
> 
> For long names I suggest a formatting like this
> 
>   Grob::maybe_pure_internal_simple_skylines_from_extents(
>     foo arg1,
>     bar arg2,
>     ...)
> 
> to avoid exactly the problem you mention.

Just to have everything jump to the right in another commit exactly where it was
when the next fixcc.py run is made over the source?

Thanks, but no thanks.  It does not make sense to stray from the indentation of
the usual formatters.

[dak, 2015-06-30 09:55:12]

Avoid skyline interruptions at line caps