Page 74	Table of Contents	Index	Page 76
	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

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CHAPTER 9. PORTS, GRAFTS, AND MIRRORED SHEETS

region. The object returned by this function is volatile, so programmers must not depend on
the components of the object remaining constant.

=> invalidate-cached-transformations sheet [Generic Function]
sheet-native-transformation and sheet-device-transformation typically cache the trans-
formations for performance reasons. invalidate-cached-transformations clears the cached
native and device values for the sheet sheet's transformation and clipping region. It is invoked
when a sheet's native transformation changes, which happens when a sheet's transformation is
changed or when invalidate-cached-transformations is called on any of its ancestors.

=> invalidate-cached-regions sheet [Generic Function]
sheet-native-region and sheet-device-region typically cache the regions for performance
reasons. invalidate-cached-regions clears the cached native and device values for the sheet
sheet's native clipping region. It is invoked when a sheet's native clipping region changes, which
happens when the clipping region changes or when invalidate-cached-regions is called on
any of its ancestors.

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Page 74	Table of Contents	Index	Page 76
	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