PS_View is a viewer for PostScript and PDF documents, available for many platforms, with binary versions prepared for i386 Linux systems and for MS Windows. PS_View uses Ghostscript, the interactive PostScript interpreter and requires Ghostscript version 8.00 or higher.
PS_View creates a graphical interface to Ghostcript which allows viewing of any document page (or several pages at the same time) in a chosen magnification, with any zooming factor, with shifts, rotations, mirror reflection, measuring, allows printing as well as image refreshing in the background and restart. PS_View uses both a menu system with accesible with mouse operations as well as many keyboard shortcuts; it also accepts PostScripts commands.
The various modules inside the PS_View program and their relations are presented in Figure 1.1.
The base module of PS_View is written in Postscript, so all program functions are realised with PostScript macros. It is possible to call those functions by entering their names (possibly preceeded by parameters, in accordance with the RPN notation of the PostScript language). All mouse operations, operations available through the menu as well as the keyboard shortcuts are being translated into respective macro calls. PS_View macros available to the user are listed in Appendix A.
The graphical user interface is handled by a Lua module which uses the wxWidgets widget toolkit (this very effective and handy combo is the result of the wxLua project). wxWidgets is a multiplatform graphical library allowing for the use of various controls and GUI functions independently of the operating system. The scripting nature of the Lua language makes it easier to modify the program and to add new functionality.