Edit: gs_dps2.ps
% Copyright (C) 2001-2019 Artifex Software, Inc. % All Rights Reserved. % % This software is provided AS-IS with no warranty, either express or % implied. % % This software is distributed under license and may not be copied, % modified or distributed except as expressly authorized under the terms % of the license contained in the file LICENSE in this distribution. % % Refer to licensing information at http://www.artifex.com or contact % Artifex Software, Inc., 1305 Grant Avenue - Suite 200, Novato, % CA 94945, U.S.A., +1(415)492-9861, for further information. % % Initialization file for basic Display PostScript functions % that are also included in Level 2. level2dict begin % ------ Errors ------ % % These errors are only defined in Level 2 and DPS. { /configurationerror /undefinedresource /unregistered } { .registererror } forall % ------ Halftones ------ % /.makestackdict { { counttomark -1 roll } forall .dicttomark } bind def /currenthalftone % - currenthalftone <dict> { mark .currenthalftone { { exch pop } % halftone { /HalftoneType 1 % screen { /Frequency /Angle /SpotFunction } //.makestackdict exec readonly } { /HalftoneType 2 % colorscreen { /RedFrequency /RedAngle /RedSpotFunction /GreenFrequency /GreenAngle /GreenSpotFunction /BlueFrequency /BlueAngle /BlueSpotFunction /GrayFrequency /GrayAngle /GraySpotFunction } //.makestackdict exec readonly } } exch get exec } odef currentdict /.makestackdict undef % Define sethalftone so it converts types 1-4 to type 5. /.makehalftoneRGBV { % <dict> <type> <keys> <keysRGBV> 4 -1 roll exch { 1 index exch get exch } forall 15 1 roll 14 -2 roll mark 15 1 roll { /Gray /Blue /Green /Red } { % stack: v0 v1 v2 type keys comp mark 2 index 0 get 8 -1 roll 4 index 1 get 9 -1 roll 6 index 2 get 10 -1 roll % stack: type keys comp mark k0 v0 k1 v1 k2 v2 /HalftoneType 10 index .dicttomark counttomark 2 roll } forall pop pop /Default 1 index .dicttomark exch pop { .sethalftone5 } } bind def % The value of each entry in .halftonetypes is a procedure: % <setdict> <htdict> <<proc>> <setdict'> <htdict'> <sethalftoneproc> % This allows us to use these procedures both for actually implementing % sethalftone and for converting subsidiary dictionaries of HalftoneType 5 % halftones. systemdict begin 15 dict /.halftonetypes 1 index def begin 1 { mark exch /Default exch .dicttomark { .sethalftone5 } } bind def 2 { 1 { /Frequency /Angle /SpotFunction } { /RedFrequency /RedAngle /RedSpotFunction /GreenFrequency /GreenAngle /GreenSpotFunction /BlueFrequency /BlueAngle /BlueSpotFunction /GrayFrequency /GrayAngle /GraySpotFunction } //.makehalftoneRGBV exec } bind def 3 { mark exch /Default exch .dicttomark { .sethalftone5 } } bind def 4 { 3 { /Width /Height /Thresholds } { /RedWidth /RedHeight /RedThresholds /GreenWidth /GreenHeight /GreenThresholds /BlueWidth /BlueHeight /BlueThresholds /GrayWidth /GrayHeight /GrayThresholds } //.makehalftoneRGBV exec } bind def 5 { pop dup length dict copy mark 1 index { % Even HalftoneType 5 dictionaries have entries other than % subsidiary halftone dictionaries. dup type /dicttype ne { 0 } { dup /HalftoneType .knownget not { 0 } if } ifelse dup 5 gt { % Stack: dict mark ... keyN dictN httypeN % Assume that all HalftoneTypes > 5 convert to 5. 1 index 3 1 roll //.halftonetypes exch get exec pop /Default get % Stack: dict mark ... keyN setdict'N htdict'N counttomark 1 add index 3 index 4 -1 roll put } { pop } ifelse } forall .dicttomark { .sethalftone5 } } bind def end end currentdict /.makehalftoneRGBV undef /sethalftone { % <dict> sethalftone - % We must create the new dictionary in the same VM as the % operand; otherwise, invalidaccess errors may occur. .currentglobal 1 .argindex dup gcheck .setglobal dup //.halftonetypes 1 index /HalftoneType get dup type /integertype ne { /sethalftone .systemvar /typecheck signalerror } if .knownget not { /sethalftone .systemvar /rangecheck signalerror } if exec exec .setglobal pop } .bind odef % Redefine setscreen and setcolorscreen to recognize halftone dictionaries, % and to insert the Frequency and Angle into Type 1 halftones, per % Adobe TN 5085. /.fixsethalftonescreen % <freq> <angle> <dict> .fix...screen % <freq> <angle> <dict> <dict'> { dup dup /HalftoneType get 1 eq { dup wcheck not { dup length dict .copydict } if dup /Frequency 5 index put dup /Angle 4 index put languagelevel 3 ge { dup /AccurateScreens dup getuserparam put } if } if } bind def /setscreen % <ignore*2> <dict> setscreen - { dup type /dicttype eq { //.fixsethalftonescreen exec sethalftone pop pop pop } { //setscreen } ifelse } .bind odef /setcolorscreen % <ignore*11> <dict> setcolorscreen - { dup type /dicttype eq { //.fixsethalftonescreen exec sethalftone 12 { pop } repeat } { //setcolorscreen } ifelse } .bind odef currentdict /.fixsethalftonescreen undef % Redefine currentscreen and currentcolorscreen to extract the Frequency % and Angle from Type 1 halftones, per Adobe TN 5085. /.fixcurrenthalftonescreen % <dict> .fix... <freq> <angle> <proc> { dup /HalftoneType get 1 eq { dup /Frequency get 1 index /Angle get } { 60.0 0.0 } % Adobe returns these as reals ifelse 3 2 roll } bind def /currentscreen % - currentscreen 60 0 <dict> { .currenthalftone { { //.fixcurrenthalftonescreen exec }% halftone { } % screen { 12 3 roll 9 { pop } repeat % colorscreen dup type /dicttype eq { //.fixcurrenthalftonescreen exec } if } } exch get exec } odef /currentcolorscreen % - currentcolorscreen (60 0 <dict>)*4 { .currenthalftone { { //.fixcurrenthalftonescreen exec 3 copy 6 copy } % halftone { % screen % The procedure might not be readable.... dup rcheck { dup length array copy cvx } if 3 copy 6 copy } { } % colorscreen } exch get exec } odef currentdict /.fixcurrenthalftonescreen undef % ------ User objects ------ % /.UserObjects { .userdict /UserObjects } bind executeonly odef % In order to get proper error recovery behavior, we need to be careful % not to pop any operands from the stack until we're done. % The code below faithfully duplicates the apparent array-growing % behavior of Adobe interpreters. /defineuserobject { % <index> <value> defineuserobject - 1 index 65535 gt { % .localvmarray throws limitcheck but CET 31-02 wants rangecheck /defineuserobject .systemvar /rangecheck signalerror } if .UserObjects .knownget { length dup 3 .argindex le { % Stack: index value len 2 index eq { 1 index 2 mul } { 1 index 1 add } ifelse .localvmarray .UserObjects get 1 index copy pop .UserObjects 3 -1 roll put } { pop } ifelse } { .UserObjects 3 .argindex 1 add 10 .max .localvmarray put } ifelse .UserObjects get 2 .argindex 2 index put pop pop } bind odef /execuserobject { % <index> execuserobject - dup type /integertype ne { % Adobe validates the argument before accessing UserObjects - CET 31-03 /execuserobject .systemvar /typecheck signalerror } if .UserObjects get 1 .argindex get exch pop exec } bind odef /undefineuserobject { % <index> undefineuserobject - dup type /integertype ne { % Adobe validates the argument before accessing UserObjects - CET 31-11 /undefineuserobject .systemvar /typecheck signalerror } if .UserObjects get 1 .argindex //null put pop } bind odef currentdict /.UserObjects undef % ------ Cache control ------ % % Dummy definitions for cache control operators /ucachestatus { % - ucachestatus -mark- ? ? ? ? <size> mark 0 0 0 0 /MaxUPathItem getuserparam } odef /setucacheparams { % -mark- ... <size> setucacheparams - % Provoke an appropriate error if needed. counttomark 1 lt { () 0 get } if dup 0 or /MaxUPathItem getuserparam .max 1 dict dup /MaxUPathItem 4 -1 roll put setuserparams cleartomark } odef end % level2dict
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