Re: Implement make-bow-stencil, make-tie-stencil for use in markup-commands undertie and overtie (issue 270640043 by address@hidden)

[thomasmorley65]

On 2015/11/10 20:52:18, dak wrote:
> https://codereview.appspot.com/270640043/diff/40001/scm/stencil.scm
> File scm/stencil.scm (right):


https://codereview.appspot.com/270640043/diff/40001/scm/stencil.scm#newcode73
> scm/stencil.scm:73: (width (- (car stop) (car start)))
> I'd not use `width' (and `height') here but `dx' and `dy': the
expectation for
> variable names `width' and `height' is that they will generally be
non-negative.


https://codereview.appspot.com/270640043/diff/40001/scm/stencil.scm#newcode81
> scm/stencil.scm:81: ;;;;     beginning '(0 . 0), ending at (cons
length-to-print
> 0)
> Ah, here's the rub.  Why end at (length-to-print . 0) instead of (1 .
0)?
> Scaling by length at the start instead of after you are done makes
things
> unnecessarily complex and indeed requires Pythagoras.  If you instead
work with
> a "unit" bow, scaling and rotating the resulting points to match some
actual
> line does not require calculating the line length but just the
equivalent of a
> complex multiplication in cartesian coordinates.


https://codereview.appspot.com/270640043/diff/40001/scm/stencil.scm#newcode123
> scm/stencil.scm:123: length-to-print)
> See?  You've effectively multiplied everything with length-to-print at
the
> start, just to divide by it again here.

> Total waste of effort.

Well, outer/inner-control rely on the user-settable variables bow-height
and thickness.
Intended is that the user may set/modify them depending on the final
bow, not the unit-bow.
Changing bow-height/thickness of the unit-bow only 0.01 will have a more
heavy impact for the
final bow than most users will expect and would be inconsistent with
setting thickness for Ties, etc.

I could hide this from the user by doing some division maybe with 10,
although the appropriate value
would be `length-to-print', which would make you not happy again... lol

I'll think about it, though, any suggestion is highly welcome as well!

https://codereview.appspot.com/270640043/