plan9fox/sys/lib/ghostscript/gs_indxd.ps

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% 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_indxd.ps,v 1.2 2002/11/13 20:23:10 alexcher Exp $
% Indexed color space method dictionary
% verify that Indexed color spaces are supported
/.setindexedspace where
{ pop }
{ currentfile closefile }
ifelse
.currentglobal true .setglobal
.cspace_util begin
%
% <num> <array> restrict_index <int> <array>
%
% Restrict the operand to setcolor for an Indexed color space to be an
% integer in the applicable range.
%
/restrict_index
{
exch round cvi
dup 0 lt
{ pop 0 }
{
1 index 2 get 2 copy gt
{ exch }
if
pop
}
ifelse
exch
}
bind def
%
% <num> <array> get_indexed_base_color <c1> ... <cn> <array>
%
% Get the base color corresponding to an indexed color value.
%
/get_indexed_base_color
{
% just in case, set the index into the appropriate range
//restrict_index exec
% lookup in the string or use the lookup proc
mark 1 index 3 get dup type /stringtype eq
{
2 index 1 get //.cs_get_ncomps exec dup 6 -1 roll mul exch getinterval
{ 255 div }
forall
}
{ 4 -1 roll exch exec }
ifelse
counttomark 2 add -2 roll pop
}
bind def
colorspacedict
/Indexed
mark
/cs_potential_indexed_base false
/cs_potential_pattern_base true
/cs_potential_alternate false
/cs_potential_icc_alternate false
/cs_get_ncomps //ncomps_1
/cs_get_range { 0 exch 2 get 2 array astore } bind
/cs_get_default_color { pop 0 } bind
/cs_get_currentgray
{ //get_indexed_base_color exec 1 get //.cs_get_currentgray exec }
bind
/cs_get_currentrgb
{ //get_indexed_base_color exec 1 get //.cs_get_currentrgb exec }
bind
/cs_get_currentcmyk
{ //get_indexed_base_color exec 1 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 //.cs_validate exec //.cs_potential_indexed_base exec not
//setcspace_rangecheck
if
dup 2 get dup type /integertype ne
//setcspace_typecheck
{
dup 0 lt exch 4095 gt or
//setcspace_rangecheck
if
}
ifelse
dup 3 get dup type /stringtype eq
{
length
1 index dup 2 get 1 add exch 1 get //.cs_get_ncomps exec mul
lt
//setcspace_rangecheck
if
}
{
//check_array exec xcheck not
//setcspace_typecheck
if
}
ifelse
}
bind
% substitute the base space if appropriate
/cs_substitute
{
dup 1 get //.cs_substitute exec 2 copy eq
{ pop pop dup }
{
% retain only the new base 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 1 4 -1 roll put
% restore VM mode
3 -1 roll .setglobal
}
ifelse
}
bind
/cs_prepare {}
%
% Install the current color space. Note that the alternative color
% space will already have been set as 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 1 get //forcesetcolorspace
% set the indexed color space; restore the earlier space on error
mark 2 index
{ .setindexedspace }
stopped
{ cleartomark setcolorspace stop }
{ pop pop pop }
ifelse
}
bind
/cs_prepare_color //validate_1
%
% Adobe implementations always execute a lookup procedure when setcolor
% is invoked. Ghostscript samples the lookup procedure when
% setcolorspace is invoked, and then does not access it again. In the
% unlikely event that an application depends on the Adobe-specific
% behavior, it is replicated in this method.
%
/cs_complete_setcolor
{
3 get dup type /stringtype eq
{ pop }
{
currentcolor exch exec
currentcolorspace 1 get //clear_setcolor_operands exec
}
ifelse
}
bind
.dicttomark
put
end % .cspace_util
.setglobal