Page 51 Table of Contents Index Page 53
Chapters
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30
A, B, C, D, E



CHAPTER 7. PROPERTIES OF SHEETS

=> children-overlapping-region sheet region [Generic Function]
=> children-overlapping-rectangle* sheet x1 y1 x2 y2 [Generic Function]
Returns the list of enabled direct children of the sheet sheet whose region overlaps the region re-
gion
. children-overlapping-rectangle* is a special case of children-overlapping-region
in which the region is a bounding rectangle whose corner points are (x1;y1) and (x2;y2). The
region is expressed in sheet's coordinate system. This function returns fresh objects that may
be modified.

Minor issue: The above three functions should really be map-over-... functions to both
avoid consing and be consistent with that convention throughout the rest of CLIM. | SWM

=> sheet-delta-transformation sheet ancestor [Generic Function]
Returns a transformation that is the composition of all of the sheet transformations between
the sheets sheet and ancestor. If ancestor is nil, sheet-delta-transformation will return the
transformation to the root of the sheet hierarchy. If ancestor is not an ancestor of sheet, the
sheet-is-not-ancestor error will be signalled.

The computation of the delta transformation is likely to be cached.

=> sheet-allocated-region sheet child [Generic Function]
Returns the visible region of the sheet child in the sheet sheet's coordinate system. If child is
occluded by any of its siblings, those siblings' regions are subtracted (using region-difference)
from child's actual region.

7.3.2 Sheet Geometry Classes

Each of the following implements the sheet geometry protocol in a different manner, according
to the sheet's requirements.

=> sheet-identity-transformation-mixin [Class]
This class is mixed into sheet classes whose coordinate system is identical to that of its parent.

=> sheet-translation-mixin [Class]
This class is mixed into sheet classes whose coordinate system is related to that of its parent by
a simple translation.

=> sheet-y-inverting-transformation-mixin [Class]
This class is mixed into sheet classes whose coordinate system is related to that of its parent by
inverting the y coordinate system, and optionally translating by some amount in x and y.

=> sheet-transformation-mixin [Class]
This class is mixed into sheet classes whose coordinate system is related to that of its parent by


Page 51 Table of Contents Index Page 53
Chapters
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30
A, B, C, D, E