The HP-RTL (Hewlett-Packard's Raster Transfer Language) is a subset of the PCL language. Generally it is used to embed true raster images (bitmaps) into plotter files. The HP-RTL language is supported since the version 4.x of SPLOT and the version 2.x of WEBPlotter. A limited support of the PCL language is also provided by these programs.
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