One thing common between different OSes is that they provide an
abstraction over graphics hardware to make developers' lives easier.
On Unix we have X Window system. On Win32 platforms - GDI. On Mac OS X
Since GTK+ is supposed to work on multiple platforms, it has a library
called GDK (GTK+ Drawing Kit) which isolates GTK+ from the details of
the windowing system.
|XWindows ||XDrawPoint() |
|GDI ||SetPixel() |
|Quartz ||You don't wanna know |
|GDK ||gdk_draw_point() |
|PHP-GTK ||gdk::draw_point() |