LispWorks CAPI User Guide > 12 Graphics Ports


12.1 Introduction


Graphics Ports implement a set of drawing functions and a mechanism for specifying the graphics state to be used in each drawing function call. There are four categories of graphics ports: on-screen, pixmap, printer, and metafile.

On-screen ports correspond to visible windows. Pixmap ports can be used for double-buffering graphics whereby you draw to the off-screen pixmap port and then copy the contents to the screen with pixblt . Printer ports are used for drawing to a printer. Metafile ports are used for recording drawing operations so that they can be realized later.

The off-screen ports (pixmap, printer and metafile) are usually created transiently by a modification of an on-screen port using with-pixmap-graphics-port , with-print-job or with-external-metafile respectively. The on-screen port is modified so that drawing is redirected as appropriate.


12.1.1 The package

12.1.2 The system

12.1.3 Creating instances

LispWorks CAPI User Guide (Macintosh version) - 22 Dec 2009