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inset
clip-descent
lift-above-baseline
drop-below-ascent
baseless
refocus
panorama
use-last
use-last*
Version: 4.1

2.5 Bounding-Box Adjusters

(inset pict amt)  pict?

  pict : pict?

  amt : real?

(inset pict h-amt v-amt)  pict?

  pict : pict?

  h-amt : real?

  v-amt : real?

(inset pict l-amt t-amt r-amt b-amt)  pict?

  pict : pict?

  l-amt : real?

  t-amt : real?

  r-amt : real?

  b-amt : real?

Extends pict’s bounding box by adding the given amounts to the corresponding sides; ascent and descent are extended, too.

(clip-descent pict)  pict?

  pict : pict?

Truncates pict’s bounding box by removing the descent part.

(lift-above-baseline pict amt)  pict?

  pict : pict?

  amt : real?

Lifts pict relative to its baseline, extending the bounding-box height if necessary.

(drop-below-ascent pict amt)  pict?

  pict : pict?

  amt : real?

Drops pict relative to its ascent line, extending the bounding-box height if necessary.

(baseless pict)  pict?

  pict : pict?

Makes the descent 0 and the ascent the same as the height.

(refocus pict sub-pict)  pict?

  pict : pict?

  sub-pict : pict?

Assuming that sub-pict can be found within pict, shifts the overall bounding box to that of sub-pict (but preserving all the drawing of pict). The last element, as reported by pict-last is also set to (or (pict-last sub-pict) sub-pict).

(panorama pict)  pict?

  pict : pict?

Shifts the given pict’s bounding box to enclose the bounding boxes of all sub-picts (even laundered picts).

(use-last pict sub-pict)  pict?

  pict : pict?

  sub-pict : pict?

Returns a pict like pict, but with the last element (as reported by pict-last) set to sub-pict. The sub-pict must exist as a sub-pict within pict.

(use-last* pict sub-pict)  pict?

  pict : pict?

  sub-pict : pict?

Propagates the last element of sub-pict to pict.

That is, use-last* is like use-last, but the last element of sub-pict is used as the new last element for pict, instead of sub-pict itself – unless (pict-last sub-pict) is #f, in which case sub-pict is used as the last element of pict.