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

[Mike Solomon]

On 24 août 2013, at 16:36, address@hidden wrote:

> On 2013/08/24 13:19:30, mike7 wrote:
> 
>> The question I'm asking is "How can I allow the user to replace the
> skyline of a
>> stencil with another shape?"
> 
> I got that.  But what is the actual use case for that?  Before skylines
> became a thing, you could override the X-extent or the Y-extent of
> grobs, independently.  There were actual use cases for that with regard
> to controlling the arrangement of marks and other things.
> 
> I repeat: isn't this interface at the same time unnecessarily general
> and restricted? It will only ever do for replacing all four skylines at
> once or none at all.  An override of four dimensions which can be +inf.0
> or -inf.0 or #f (namely, just use the original skyline for this
> dimension) for different effects seems to fit the known use cases
> better.

To me, it seems like the most critical thing is making the various padding and 
dimension functions work again.  This patch does that with little coding in C++ 
and most of it being done in Scheme.  It allows eventually for more 
sophisticated padding.

Your suggestion for four different skyline replacements is possible to 
implement through stencil operators.  That is, we can implement stencil union 
and stencil intersect functions that keep or reject different sides of a 
stencil.  This way, we don't need to specify four different stencils for the 
four different skylines.

Cheers,
MS