Expose ImageBrush source region constructor.

[JimBobSquarePants]

Prerequisites

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Description

See #305 The public constructor is required to selecting the source region providing the ability to negative offset and image.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (2316146) 80% compared to head (3ee51ef) 80%.

Additional details and impacted files

@@         Coverage Diff         @@
##           main   #306   +/-   ##
===================================
  Coverage    80%    80%           
===================================
  Files        97     97           
  Lines      4946   4946           
  Branches    884    884           
===================================
  Hits       3997   3997           
  Misses      754    754           
  Partials    195    195           

Flag	Coverage Δ
unittests	80% <100%> (ø)

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