IRIS IM is Silicon Graphics' port of OSF/Motif for use on Silicon Graphics IRIS workstations. Figure 4-1 shows the relationship of an application to the various user interface libraries you might choose to use.
Figure 4-1 : Hierarchy of User Interface Toolkits The application programming interface (API) to IRIS IM is the same as that for OSF/Motif. However, Silicon Graphics has modified the appearance of some IRIS IM widgets so that they conform to the Silicon Graphics user interface style. You can select either the OSF/Motif or the IRIS IM widget set for use with your application, although using IRIS IM widgets is preferable because their appearance conforms to the Indigo Magic style.
In addition to the low-level building blocks such as buttons and scrollbars that IRIS IM provides, it also supplies some related software that isn't part of the standard OSF/Motif. This includes the GLwMDrawingArea widget for IRIS IM programs that use OpenGL to draw to a window within an IRIS IM application.