IDL Graphics vs. Direct Graphics

IDL Graphics were introduced in IDL 8.0, providing a simple and powerful way to visualize data. IDL Graphics are the preferred method to view data in IDL because the functions are easy to use and the graphics can be modified after visualization.

For more information, please see Using IDL Graphics for visual examples of the many ways you can use these functions.

For a listing of the newer IDL Graphics functions: IDL Graphics List

For a listing of the older Direct Graphics functions: Direct Graphics List

IDL Direct Graphics

IDL Direct Graphics is the original graphics rendering system introduced in IDL. Graphic displays creating using Direct Graphics are static; once created, no changes can be made without recreating the visualization being displayed. If you have used routines such as PLOT or SURFACE, you are already familiar with this graphics system. The salient features of Direct Graphics are:

• Direct Graphics use a graphics device (X for X-windows systems displays, WIN for Microsoft Windows displays, PS for PostScript files, etc.). You switch between graphics devices using the SET_PLOT Procedure command, and control the features of the current graphics device using the DEVICE Procedure command.
• Once a direct-mode graphic is drawn to the graphics device, it cannot be altered or re-used. This means that to re-create the graphic on a different device, you must re-issue the IDL commands to create the graphic.
• When you add a new item to an existing direct-mode graphic (using a routine like OPLOT or XYOUTS), the new item is drawn in front of the existing items.