libgdiplus

Libgdiplus is the Mono library that provides a GDI+-compatible API on non-Windows operating systems. Our implementation uses Cairo to do most of the heavy lifting.

Mono’s implementation of GDI+ lives in the libgdiplus git module and includes its own internal copy of Cairo (version 1.6.4) but will use a newer system version when available (since Mono 2.4).

See here if you’re having problems initializing libgdiplus.

Plans

Due to its tight relation with System.Drawing, new versions of libgdiplus are released with (almost) every new version of Mono.

Text

The current custom text engine is limited. GDI+ offers many (little used) options that are not, or incorrectly, supported by libgdiplus. The plan is to use Pango to replace our custom engine—but no work is being done on this task at the moment.

A proof-of-concept is already in git but is unsupported and less complete than the current text engine. You can use –with-pango to enable it. Note that this will work only if you are building libgdiplus with the system cairo, i.e. if your cairo library is newer than version 1.6.4.

Other Tasks

Cairo doesn’t provide 100% of the functionalities required to implement GDI+ or System.Drawing. A few features were added directly in libgdiplus (unmanaged) or System.Drawing (managed). However some features are still missing.

• add missing implementation for
  • path gradient brush
  • path widen
  • path warp
• other missing stuff required for System.Drawing (file bugs for them)
• other missing stuff, e.g. parts of the GDI+ API isn’t exposed in System.Drawing (file bugs for them)

Contributions toward completing those tasks are welcome.