Ten desktop test classes drew the same squares and the same 4 x 2
rectangle in private helpers, in two equivalent styles. They now use
TestPrograms.Square, ClockwiseSquare and Rectangle.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
ColorScheme.Default and LayoutPart kept single static pens, brushes and a
font that every plate view and drawing preview painted with. GDI+ objects
are not thread-safe, so two views painting at once on different UI threads
(parallel WinForms test collections) failed in PlateRenderer.DrawPlate with
"Object is currently in use elsewhere" and crashed the test host.
The scheme now builds its pens and brushes per thread and rebuilds them
after a color change; LayoutPart's selection, lead-in and label objects are
thread-static. A regression test paints previews on four threads at once.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
ajandClaude Opus 5.5