[Lazarus] LCL based image viewer like ACDSee?

[Graeme Geldenhuys]

Delphi rectangles are used to wrap Win32 GDI calls.

here's a quote from msdn FillRect function:
-= start quote =-
When filling the specified rectangle, FillRect does not include the
rectangle's right and bottom sides. GDI fills a rectangle up to, but
not including, the right column and bottom row, regardless of the
current mapping mode.
-= end of quote =-

so function ptInRect can be determined if point is inside filled rect or not.