## Changes Introduced in V9.2.12

The following describes the most significant changes which occurred in the AST library between versions V9.2.11 and V9.2.12:

1. A new attribute called IgnoreBadAltIgnoreBadAlt has been added to the FitsChanFitsChan class. If set, it allows unreadable alternate axis descriptions within FITS-WCS headers to be ignored. By default, such headers would cause an error to be reported.
2. A new warning called BadAlt has been added to the FitsChan class. If included in the list of active warnings (see attribute “WarningsWarnings”), a warning will be created if any alternate axes are ignored when reading a FITS-WCS header.
3. The FitsChan class now supports 64 bit integer keyword values.
4. The TableTable class now supports 64 bit integer columns.
5. The FitsTableFitsTable class now supports 64 bit integer columns.
6. The MinOrderMinOrder attribute of the MocMoc class can be higher than MaxOrderMaxOrder to allow small features to be included in a lower-resolution MOC when using astAddPixelMask or astAddRegionastAddRegion with a non-MOC region. (It should no longer be set to a very large value to have MaxOrder used instead in these methods.)
7. When adding FITS data or string representation to a Moc object, cells of greater order than the MaxOrder attribute will be degraded to that resolution.
8. Tracing the outline of a Moc region (via the surface mesh) has hopefully been made more reliable with the addition of backtracking.
9. Added a check for an acos parameter being out of range in internal line length calculation in SkyFrameSkyFrame.
10. BoxBox simplification to PolygonPolygon in a SkyFrame checks handedness without using astGetBounded.