Re: Boxed text with rounded corners

[Valentin Villenave]

Greetings folks,

I have sent this mail on -user a few days ago; perhaps it would belong
to -devel instead (if so, please tell me), or even to the tracker as a
feature request (which I, of course, won't decide on my own).

Anyway, it would be just great if anybody had a clue about how to deal
with this issue? If so, the winner will have his solution exposed in a
whole new LSR-snippet, will be mentioned in the LilyPond Report's
"feature of the week" and his name will be glorified forever -- at
least until next week's :)

Valentin

2008/3/28, Valentin Villenave <address@hidden>:
> Hi everybody,
>
>  There are two features (among others) I appreciate very much In
>  LilyPond: \box and \filled-box.
>
>  Would there be any possibility to somehow mix these two commands?
>
>  For instance, is it possible to add an optionnal "blot" argument to
>  the make-stencil-boxer function? If specified, the corners will be
>  rounded; if not, the corners will be sharp.
>
>  I tried to have a look at stencil.scm, define-markup-commands.scm,
>  lookup.cc and text-interface.cc, but I am definitely not a programmer
>  (see below).
>
>  Here are some questions I couldn't solve:
>
>  1-how to obtain a non-filled rounded box? The only solution I can see would 
> to:
>     -draw a black-filled box slightly too large
>     -then draw a white-filled box on top of it (#:whiteout or something?)
>     -then print the text on the white box (#:combine or something?)
>
>  It's complicated; however I found that some objects are already
>  printed using this "dirty way:
>  http://lists.gnu.org/archive/html/lilypond-devel/2006-04/msg00264.html
>
>  2-how exactly does ly:stencil-extent work? is it possible to obtain
>  the width and length of an object *prior* to drawing it?
>
>  3-Here's some code to demonstrate my idea. It's very dirty but perhaps
>  you'll see what I'm trying to achieve.
>
>  #(define-markup-command (rbox layout props radius text) (number?) (markup?)
>  "Add a rounded box around the text"
>   (let* ((th (*
>               (ly:output-def-lookup layout 'line-thickness)
>               (chain-assoc-get 'thickness props 1)))
>          (size (chain-assoc-get 'font-size props 0))
>          (pad (* (magstep size)
>                  (chain-assoc-get 'box-padding props 0.2)))
>          (m (interpret-markup layout props text)))
>    (let* ((x-ext (interval-widen (ly:stencil-extent m 0) (+ pad th)))
>      (y-ext (interval-widen (ly:stencil-extent m 1) (+ pad th)))
>      (xext (cons (- (/ x-ext 2)) (/ x-ext 2)))
>      (yext (cons (- (/ y-ext 2)) (/ y-ext 2)))
>      (blot radius))
>      (markup (ly:round-filled-box xext yext blot)))
>    (let* ((x-ext (interval-widen (ly:stencil-extent m 0) pad))
>      (y-ext (interval-widen (ly:stencil-extent m 1) pad))
>      (xext (cons (- (/ x-ext 2)) (/ x-ext 2)))
>      (yext (cons (- (/ y-ext 2)) (/ y-ext 2)))
>      (blot radius))
>      (markup #:with-color (rgb-color 1 1 1) #:filled-box xext yext blot))
>    (markup m)))
>
>  Besides, this could allow interesting Editorial uses: this way
>  \balloonText could look like "real" balloons :)
>
>  Cheers,
>
> Valentin