Scintilla is a free source code editing component for Win32 and GTK+. As well as features found in standard text editing components, Scintilla includes features especially useful when editing and debugging source code. These include support for syntax styling, error indicators, code completion and call tips. Styling choices are more open than with many editors, allowing the use of proportional fonts, bold and italics, multiple foreground and background colours and multiple fonts.
Tcl provides a portable scripting environment for Unix, Windows, and Macintosh that supports string processing and pattern matching, native file system access, shell-like control over other programs, TCP/IP networking, timers, and event-driven I/O. Tcl has traditional programming constructs like variables, loops, procedures, namespaces, error handling, script packages, and dynamic loading of DLLs. Tk provides portable GUIs on UNIX, Windows, and Macintosh. A powerful widget set and the concise scripting interface to Tk make it a breeze to develop sophisticated user interfaces.
Prima is an extensible Perl toolkit for multi-platform GUI development. Supported platforms include Linux, Windows NT/9x/2K, OS/2, and UNIX/X11 workstations (FreeBSD, IRIX, SunOS, Solaris, and others). The toolkit contains a rich set of standard widgets and has emphasis on 2D image processing tasks. A Perl program using Prima looks and behaves identically on X, Win32, and OS/2 PM.
The Xmt Library provides nine custom widgets and over 260 convenience functions designed to make Motif user interface development easier for beginning and advanced programmers. It provides an alternative tool chain that avoids the use of GUI builders. The essence of this approach is to program from the resources file using an extended vocabulary for automatic creation of the widget hierarchy, dynamic layout, and to provide a rapid prototype environment.
ClassyTk is an extension of Tk based on the ClassyTcl Object system. It adds a lot of improvements to Tk, ranging from drag and drop support (between Tk apps) and a configuration system to a large set of new widgets and commands, written using the object system. It also contains a GUI Builder that can be used to graphically create interfaces. It is invoked via the cbuild command in the bin directory. There are also some sample (but useable) applications created with ClassyTk: a very useable editor, a calculator, a drawing program, and more.