% Copyright (C) 2001, 2002 Aladdin Enterprises. 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. % % For more information about licensing, please refer to % http://www.ghostscript.com/licensing/. For information on % commercial licensing, go to http://www.artifex.com/licensing/ or % contact Artifex Software, Inc., 101 Lucas Valley Road #110, % San Rafael, CA 94903, U.S.A., +1(415)492-9861. % $Id: gs_sepr.ps,v 1.3 2003/04/26 18:40:16 dan Exp $ % Separation color space method dictionary % verify that Separation color spaces are supported /.setseparationspace where { pop } { currentfile closefile } ifelse .currentglobal true .setglobal .cspace_util begin % % apply_sepr_tint_xform ' ... ' % % Apply the tint transform for a Separation color space color intensity % value. % /apply_sepr_tint_xform { exch //bound_0_1 exec mark exch 2 index 3 get exec counttomark 2 add -2 roll pop } bind def % % build_tintxform_function % % Convert a tint transformation into a function, if possible. If this is % successful, will be a function procedure (a two-element, % execute-only, executable array whose first element is the function % data structure and whose second element is the operator %execfunction. % If it is not successful, will be the same as the tint transform % in . % % Note that, for PDF files, the tint transform will likely already be a % function-array. In this case, will be this array, and thus will % also be identical to the original tint transform. % % This procedure is used for both Separation and DeviceN color spaces. % /build_tintxform_function { dup 3 get dup .isencapfunction not { % Try a FunctionType 4 function first; build the function dictionary % in local VM. .currentglobal exch //false .setglobal % Make the dictionary a couple of elements large in case this fails % and we need the dictionary to build a sampled function. 6 dict begin /FunctionType 4 def /Function exch def /Domain 2 index //.cs_get_range exec def /Range 2 index 2 get //.cs_get_range exec def currentdict end { .buildfunction } .internalstopped % If .buildfunction fails then not type 4 func. { % If not then try building a sampled (type 0) func. % We are using the dictionary which was created before .buildfunction dup /Order 3 put dup /BitsPerSample 16 put { .buildsampledfunction } .internalstopped % If .buildsamplefunction fails then invalid func. { % Failed - Create a dummy tint transform function % We are using the dictionary which was created before .buildfunction dup /Function {} put % Replace invalid tint transform with dummy .buildfunction } if % Check status from .buildsamplefunction/.internalstopped } if % check status from .buildfunction/.intermalstopped % restore the VM mode exch .setglobal } if } bind def % % converttinttransform % % Convert a Separation/DeviceN color space to use a function as a tint % transformation, if this is possible. Possible outcomes are: % % 1. The tint transform already is a function, or is a procedure that % cannot be converted to a function. In either case, is % left unchanged ( == ). % % 2. The tint transform is not already a function but can be converted % to a function, and != . In this case, % is modified directly. % % 3. The tint transform is not already a function but can be converted % to a function, and == . In this case, % is copied, and the copy is modified (i.e., after the operation % != % % This slightly complex approach avoids creating an extra color space % array unnecessarily. % /converttinttransform { % convert the tint transform to a fucntion //build_tintxform_function exec % see if anything needs to be modified 1 index 3 get 2 copy eq { pop pop } { pop % see if the color space must be copied 3 copy pop eq { % copy the array into local VM .currentglobal //false .setglobal 3 -1 roll dup length array copy 3 1 roll .setglobal } if 1 index exch 3 exch put } ifelse } bind def colorspacedict /Separation mark /cs_potential_indexed_base true /cs_potential_pattern_base true /cs_potential_alternate false /cs_potential_icc_alternate false /cs_get_ncomps //ncomps_1 /cs_get_range //get_range_1 /cs_get_default_color { pop 1 } bind /cs_get_currentgray { //apply_sepr_tint_xform exec 2 get //.cs_get_currentgray exec } bind /cs_get_currentrgb { //apply_sepr_tint_xform exec 2 get //.cs_get_currentrgb exec } bind /cs_get_currentcmyk { //apply_sepr_tint_xform exec 2 get //.cs_get_currentcmyk exec } bind % a lot of validation is done by the cs_validate method /cs_validate { //check_array exec dup 1 get type dup /nametype ne exch /stringtype ne and //setcspace_typecheck if dup 2 get //.cs_validate exec //.cs_potential_alternate exec not //setcspace_rangecheck if dup 3 get //check_array exec xcheck not //setcspace_typecheck if } bind % substitute the base space if appropriate /cs_substitute { dup 2 get //.cs_substitute exec 2 copy eq { pop pop dup } { % retain only the new alternate space exch pop % build all new structures in local VM .currentglobal 3 1 roll //false .setglobal % construct a new array and insert the new base color space 1 index dup length array copy dup 2 4 -1 roll put % restore VM mode 3 -1 roll .setglobal } ifelse } bind % % The Ghostscript interpreter works better when tinttransform procedures % are translated into functions. Attempt to do that here. % /cs_prepare //converttinttransform % % Install the current color space. % % The current Ghostscript color space implementation requires that % color spaces that provide a base or alternative color space set % that base/alternative color space to be the current color space % before attempting to set the original color space. % /cs_install { % save the current color space currentcolorspace % set the base color space as the current color space 1 index 2 get //forcesetcolorspace % set the indexed color space; restore the earlier space on error mark 2 index { .setseparationspace } stopped { cleartomark setcolorspace stop } { pop pop pop } ifelse } bind /cs_prepare_color //validate_1 % % If a Separation color space is not supported in native mode by % the current process color model, Adobe implementations will always % execute the tint transform procedure when setcolor is invoked. % Ghostscript may have turned this transform into a sampled function, % and even if this is not the case, will have sampled the transform % when the color space is first set. Some applications may depend % on the Adobe behavior, so we implement it via the % cs_complete_setcolor method. % /cs_complete_setcolor { .usealternate { currentcolor exch 3 get exec currentcolorspace 2 get //clear_setcolor_operands exec } { pop } ifelse } bind .dicttomark put end % .cspace_util .setglobal