Re: Adds dimension stencil command to correct with-dimension (issue 12957047)

[Mike Solomon]

On 26 août 2013, at 08:20, address@hidden wrote:

> On 2013/08/26 04:51:50, mike7 wrote:
>> On 26 août 2013, at 07:36, mailto:address@hidden wrote:
> 
>> > On 2013/08/26 04:08:17, mike7 wrote:
>> >> On 25 août 2013, at 16:04, mailto:address@hidden wrote:
>> >
>> >> > On 2013/08/25 08:22:01, mike7 wrote:
>> >> >> On 25 août 2013, at 09:15, mailto:address@hidden wrote:
>> >> >
>> >> >> > A second stencil is not a very good data structure for
> reserving
>> >> > space.
>> >> >> > Skylines are better at this, and we can \once\override
> 'padding
>> > and
>> >> >> > 'horizon-padding to get padding that follows the outlines of
> the
>> >> >> > stencil.
>> >> >> [...]
>> >> >> If
>> >> >> we're going to do that, then we should think of the general
> problem
>> >> > we're trying
>> >> >> to solve.  To me, the general problem seems to be "how can we
>> > replace
>> >> > the
>> >> >> outline of one shape with that of another?"
>> >> >
>> >> > No, that is _absolutely_ not the general problem here.  The
> general
>> >> > problem is: "how can we replace the outline/skylines of one
> stencil
>> > with
>> >> > a different outline/skyline?"
>> >> >
>> >
>> >> It seems like what would make sense is for stencils to carry their
> own
>> > skyline
>> >> information, much like they carry their own dimension information.
>> >
>> > So what?  Whether or not the skyline is cached or even persistent is
>> > completely orthogonal to the issue at hand, namely what we want to
> be
>> > able to override a stencil's skyline in stencil-integration with.
> 
>> It changes the amount of work required to arrive at a solution.
> 
> Indeed.  Instead of calling stencil-integrate on a "surrogate stencil"
> or whatever for deriving a skyline, the respective stencil operation in
> stencil-integrate will just plug in a a "surrogate skyline" directly
> specified in the stencil operation and be done.
> 
> Which is less work.

What is more work is what I talk about farther down in my previous e-mail.

It is possible to create a stencil primitive that works something like:

`(replacement-skylines ,left ,right, ,up ,down original-stencil)

but that seems kludgy.  It would be better and more consistent with currently 
practices in the code base if stencils carried their own skyline information 
(as they do their own dimensions), which would require a lot of juggling code 
around.

Cheers,
MS