PATH Mac OS 8 and 9 Developer Documentation > Text and Other International Services > Apple Type Services for Unicode Imaging (ATSUI) > Apple Type Services for Unicode Imaging Reference

Justification Override Mask Constants

You can use a mask constant of type JustificationFlags in the growFlags and shrinkFlags fields of a width delta override structure of a particular justification priority. There are four width delta override structures, one for each justification priority, in an array of structures of type ATSJustPriorityWidthDeltaOverrides.

In the growFlags field of the width delta override structure, these masks indicate whether ATSUI should apply the limits defined in the beforeGrowLimit and afterGrowLimit fields, as well as whether unlimited gap absorption should be applied to the priority of glyphs specified in the given width delta override structure.

In the shrinkFlags field, these masks indicate whether ATSUI should apply the limits defined in the beforeShrinkLimit and afterShrinkLimit fields, as well as whether unlimited gap absorption should be applied to the priority of glyphs specified in the given width delta override structure.

Note that these mask constants are a specialized override. You should not use them unless you know the details of what is occurring in the font.

enum { kJUSTOverridePriority = 0x8000, kJUSTOverrideLimits = 0x4000, kJUSTOverrideUnlimited = 0x2000, kJUSTUnlimited = 0x1000, kJUSTPriorityMask = 0x0003 }; typedef UInt16 JustificationFlags;

Constant descriptions

kJUSTOverridePriority: If the bit specified by this mask is set, ATSUI uses the justification priority set in the kJUSTPriorityMask mask. If this flag is cleared, ATSUI uses the default justification priority for those glyphs. In this case, the kJUSTPriorityMask mask bits must also be set to 0.
kJUSTOverrideLimits: If the bit specified by this mask is set, ATSUI uses the grow and shrink limit values set in the array of ATSJustPriorityWidthDeltaOverrides structures. If this bit is cleared, ATSUI uses the default grow and shrink limits for those glyphs. In this case, the limits values in the width delta structure must also be set to 0.
kJUSTOverrideUnlimited: If the bit specified by this mask is set, ATSUI takes into account the state of the kJUSTUnlimited mask constant. If this bit is cleared, the bit specified by the kJUSTUnlimited mask constant must also be set to 0.
kJUSTUnlimited: If the bit specified by this mask is set, ATSUI distributes all remaining justification gap, even if it violates the grow or shrink limits specified in the width delta override structure specified in the array of ATSJustPriorityWidthDeltaOverrides structures. If this bit is set, you must also set the bit specified by the kJUSTOverrideUnlimited mask constant.
kJUSTPriorityMask: If the bit specified by this mask is set, ATSUI identifies the new justification priority for the glyphs this width delta structure applies to. See Justification Priority Constants for a description of possible values. Only a single valid justification priority value is permitted. If this bit is set, the bit specified by the mask constant kJUSTOverrideLimit must also be set.