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https://issues.apache.org/jira/browse/SIS-550?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Martin Desruisseaux resolved SIS-550.
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Resolution: Fixed
Done also for Polar stereographic and Lambert Conic Conformal projections. It
does not cover all projections, but at least the ones we could do easily.
> Give estimation of MathTransform domain
> ---------------------------------------
>
> Key: SIS-550
> URL: https://issues.apache.org/jira/browse/SIS-550
> Project: Spatial Information Systems
> Issue Type: Improvement
> Components: Referencing
> Affects Versions: 1.2
> Reporter: Martin Desruisseaux
> Assignee: Martin Desruisseaux
> Priority: Major
> Fix For: 1.3
>
>
> Provides a way to get the ranges of coordinate values which can be used as
> inputs in a {{MathTransform}}. They are limits where the transform is
> mathematically and numerically applicable. This is *not* the domain of
> validity for which a coordinate reference system has been defined, because
> the new method ignores "real world" considerations such as datum and country
> boundaries.
> The new method is for allowing callers to crop their data for removing areas
> that may cause numerical problems. For example results of Mercator projection
> tend to infinity when the latitude value approaches a pole. For avoiding data
> structures with unreasonably large values or NaN, we commonly crop data to
> some arbitrary maximal latitude value (typically 80 or 84°) before
> projection. Those limits are arbitrary, the transform does not become
> suddenly invalid after a limit. The new API will need to be extensible for
> allowing (in the future) some controls on the criteria for choosing a limit.
> Many transforms, in particular all affine transforms, have no mathematical
> limits. Again it does not mean that the coordinate operation has no
> geospatial domain of validity, but the latter is not the purpose of this
> method. The new method is (for example) for preventing a viewer to crash when
> attempting to render a world-wide image.
> A difficulty is that {{MathTransforms}} are usually part of a larger chain of
> transform steps. Users and implementers should not need to search through
> transform steps. It should be done automatically by SIS implementation of
> {{ConcatenatedTransform}}.
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