Xerox 721P87491 manual PostScript storage object size limits, Arc to Bezier conversion-pathforall

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POSTSCRIPT

Figure 2-7.Typical desktop printer device coordinate

PostScript storage object size limits

The two main PostScript storage objects are the font cache and virtual memory (VM), which stores composite PostScript data structures such as the user and system dictionaries. The font cache, VM, and data structures in VM do not have standard sizes. Therefore, test masters that print out these object sizes are useless for testing consistency across different PostScript printers.

A small font cache size does not normally cause a PostScript master to fail; it should affect only performance.

Refer to the PostScript Language Reference Manual for typical memory limits for PostScript products. These limits should be considered minimum values.

Obsolete operators—banddevice, framedevice, renderbands

The banddevice, framedevice, and renderbands operators are obsolete and should not be used. These operators were not meant to be included in page descriptions and were used only in certain implementations for device setup.

Arc to Bezier conversion—pathforall

The pathforall operator returns the components of the current path. Path components arc, arcn, and arcto are converted to sequences of curveto components. The standard does not define the arc to Bezier (curveto) conversion algorithm. Therefore, different PostScript implementations may return different pathforall results.

Note: All PostScript implementations should return the same equivalent path, but the path may be composed of a different number of curveto components. PostScript masters that depend on a particular arc to Bezier conversion algorithm may not be consistent across different PostScript printers.

2-26	XEROX DOCUPRINT NPS GUIDE TO USING PAGE DESCRIPTION LANGUAGES

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Contents Version 7.1 August 2000 721P87491 Page Operation safety Laser safetyOzone information Conductor may result in risk of electrical shock. grounding Table of contents PostScript Vipp IndexViii About this guide ContentsConventions Introduction Related information Related publicationsPostScript publications HP PCL 5 publications Vipp publicationPCL Maintaining image qualityOFF PCL 5 media support PCL 5 font supportPCL 5 fonts installed with NPS software PJL commands PCL command supportPCL Copy command PCL Copy command example Duplex PCL Copy command examplePCL Duplex commands PCL Duplex commands DocuPrint NPS Collated HP LaserJet 4siPCL Job Separation command PCL Paper Source command tray assignment PCL media selectionPrecedence in selecting media PCL Output Bin command PCL Offset Registration commandsPCL 5c support PCL 5 coding recommendationsPCL 5c coding recommendations PCL 5c functions not applicable to DocuPrint NPSDriver recommendations for PCL 5c Limitations for custom PCL 5c driversImplementation-dependent operations Coordinate system default matrixFloating-point arithmetic and math operators Adobe Type1 PostScript fonts FontsFont Typeface Loading fonts User-defined fontsUsing Adobe Type 1 fonts Type 1 fontsUsing a Type 1 font in a document Producing Type 1 fonts for use with DocuPrintPostScript language extensions PostScript with embedded PJL commandsSystem Dict User Dict Server DictIdleTime Dictionary Status DictDfltkIdleArry needflush Nonstandard definitions Printer resolution and resolution enhancement Appearance consistencyExamples of nonstandard definitions Statusdict UserdictDpi image Printed on a 300 dpi printer Printer imaging characteristics Font consistency Proprietary PostScript extensionsControl-Z and superfluous errors Control-D as binary data and end-of-jobSolution to control-Z and control-D problems Multiple jobs in one input file DocuPrint NPS implementation of PostScript Level Simulated mixed plexScan conversion details Printer Controller operationsStroke Fill ShapesCurved shapes Zero-width lines strokesImages Image quality Rendering of color and gray values transfer function PostScript printer description PPD files Implementation limitsImplementation limits File operators and standard devicesQuantity Limit Description Path limits PostScript VM limitsSetCacheDevice Device orientation and setscreen operatorObsolete operators-banddevice, framedevice, renderbands PostScript storage object size limitsArc to Bezier conversion-pathforall Print performance related to image printing Creating the necessary PostScript Ccitt Group 3Scan order and rotation Purpose Image orientation mismatch aImage orientation mismatch B 10.Image pixel sequence example Considerations SummaryScan resolution and scaling 11.Scaling and resolution example12.PostScript with embedded image normal scan order MaxX exch def /minY exch def /minX exch def 14.Actual PostScript print Page Vipp Functionality Operating environmentVipp line mode extension XGFNub Page Symbols CcittIndex PCL PPD Index