Файл .ps не открывается ни в каком программном обеспечении, которое я пробовал - что может быть не так с синтаксисом файла?

Question

У меня есть файл postscript, который не открывается в Adobe или Preview. Этот файл .ps представляет собой вывод следующего:

1. Нарисуйте узел (например, 5-1) в программном обеспечении под названием «Knotscape».
2. Сохраните чертеж в виде файла postscript.

Я предполагаю, что в моем файле ps есть проблема с синтаксисом, которую последние версии Adobe или Prview больше не принимают. Если бы кто-то мог помочь указать, где эта проблема и, возможно, как ее исправить, я был бы очень благодарен.

Вот код этого файла .ps:

%!PS-Adobe-3.0 EPSF-3.0
%%Creator: Tk Canvas Widget
%%For: Van Pham
%%Title: Window .drawing0.c
%%CreationDate: Wed Jan  8 14:05:32 2020
%%BoundingBox: 306 396 308 398
%%Pages: 1
%%DocumentData: Clean7Bit
%%Orientation: Portrait
%%EndComments

%%BeginProlog
/CurrentEncoding [
/space/space/space/space/space/space/space/space
/space/space/space/space/space/space/space/space
/space/space/space/space/space/space/space/space
/space/space/space/space/space/space/space/space
/space/exclam/quotedbl/numbersign/dollar/percent/ampersand/quotesingle
/parenleft/parenright/asterisk/plus/comma/hyphen/period/slash
/zero/one/two/three/four/five/six/seven
/eight/nine/colon/semicolon/less/equal/greater/question
/at/A/B/C/D/E/F/G
/H/I/J/K/L/M/N/O
/P/Q/R/S/T/U/V/W
/X/Y/Z/bracketleft/backslash/bracketright/asciicircum/underscore
/grave/a/b/c/d/e/f/g
/h/i/j/k/l/m/n/o
/p/q/r/s/t/u/v/w
/x/y/z/braceleft/bar/braceright/asciitilde/space
/space/space/space/space/space/space/space/space
/space/space/space/space/space/space/space/space
/space/space/space/space/space/space/space/space
/space/space/space/space/space/space/space/space
/space/exclamdown/cent/sterling/currency/yen/brokenbar/section
/dieresis/copyright/ordfeminine/guillemotleft/logicalnot/hyphen/registered/macron
/degree/plusminus/twosuperior/threesuperior/acute/mu/paragraph/periodcentered
/cedilla/onesuperior/ordmasculine/guillemotright/onequarter/onehalf/threequarters/questiondown
/Agrave/Aacute/Acircumflex/Atilde/Adieresis/Aring/AE/Ccedilla
/Egrave/Eacute/Ecircumflex/Edieresis/Igrave/Iacute/Icircumflex/Idieresis
/Eth/Ntilde/Ograve/Oacute/Ocircumflex/Otilde/Odieresis/multiply
/Oslash/Ugrave/Uacute/Ucircumflex/Udieresis/Yacute/Thorn/germandbls
/agrave/aacute/acircumflex/atilde/adieresis/aring/ae/ccedilla
/egrave/eacute/ecircumflex/edieresis/igrave/iacute/icircumflex/idieresis
/eth/ntilde/ograve/oacute/ocircumflex/otilde/odieresis/divide
/oslash/ugrave/uacute/ucircumflex/udieresis/yacute/thorn/ydieresis
] def

50 dict begin
% This is a standard prolog for Postscript generated by Tk's canvas
% widget.
% RCS: @(#) $Id$

% The definitions below just define all of the variables used in
% any of the procedures here.  This is needed for obscure reasons
% explained on p. 716 of the Postscript manual (Section H.2.7,
% "Initializing Variables," in the section on Encapsulated Postscript).

/baseline 0 def
/stipimage 0 def
/height 0 def
/justify 0 def
/lineLength 0 def
/spacing 0 def
/stipple 0 def
/strings 0 def
/xoffset 0 def
/yoffset 0 def
/tmpstip null def


/cstringshow {
    {
    dup type /stringtype eq
    { show } { glyphshow }
    ifelse
    }
    forall
} bind def



/cstringwidth {
    0 exch 0 exch
    {
    dup type /stringtype eq
    { stringwidth } { 
        currentfont /Encoding get exch 1 exch put (\001) stringwidth 
        }
    ifelse 
    exch 3 1 roll add 3 1 roll add exch
    }
    forall
} bind def

% font ISOEncode font
% This procedure changes the encoding of a font from the default
% Postscript encoding to current system encoding.  It's typically invoked just
% before invoking "setfont".  The body of this procedure comes from
% Section 5.6.1 of the Postscript book.

/ISOEncode {
    dup length dict begin
    {1 index /FID ne {def} {pop pop} ifelse} forall
    /Encoding CurrentEncoding def
    currentdict
    end

    % I'm not sure why it's necessary to use "definefont" on this new
    % font, but it seems to be important; just use the name "Temporary"
    % for the font.

    /Temporary exch definefont
} bind def

% StrokeClip
%
% This procedure converts the current path into a clip area under
% the assumption of stroking.  It's a bit tricky because some Postscript
% interpreters get errors during strokepath for dashed lines.  If
% this happens then turn off dashes and try again.

/StrokeClip {
    {strokepath} stopped {
    (This Postscript printer gets limitcheck overflows when) =
    (stippling dashed lines;  lines will be printed solid instead.) =
    [] 0 setdash strokepath} if
    clip
} bind def

% desiredSize EvenPixels closestSize
%
% The procedure below is used for stippling.  Given the optimal size
% of a dot in a stipple pattern in the current user coordinate system,
% compute the closest size that is an exact multiple of the device's
% pixel size.  This allows stipple patterns to be displayed without
% aliasing effects.

/EvenPixels {
    % Compute exact number of device pixels per stipple dot.
    dup 0 matrix currentmatrix dtransform
    dup mul exch dup mul add sqrt

    % Round to an integer, make sure the number is at least 1, and compute
    % user coord distance corresponding to this.
    dup round dup 1 lt {pop 1} if
    exch div mul
} bind def

% width height string StippleFill --
%
% Given a path already set up and a clipping region generated from
% it, this procedure will fill the clipping region with a stipple
% pattern.  "String" contains a proper image description of the
% stipple pattern and "width" and "height" give its dimensions.  Each
% stipple dot is assumed to be about one unit across in the current
% user coordinate system.  This procedure trashes the graphics state.

/StippleFill {
    % The following code is needed to work around a NeWSprint bug.

    /tmpstip 1 index def

    % Change the scaling so that one user unit in user coordinates
    % corresponds to the size of one stipple dot.
    1 EvenPixels dup scale

    % Compute the bounding box occupied by the path (which is now
    % the clipping region), and round the lower coordinates down
    % to the nearest starting point for the stipple pattern.  Be
    % careful about negative numbers, since the rounding works
    % differently on them.

    pathbbox
    4 2 roll
    5 index div dup 0 lt {1 sub} if cvi 5 index mul 4 1 roll
    6 index div dup 0 lt {1 sub} if cvi 6 index mul 3 2 roll

    % Stack now: width height string y1 y2 x1 x2
    % Below is a doubly-nested for loop to iterate across this area
    % in units of the stipple pattern size, going up columns then
    % across rows, blasting out a stipple-pattern-sized rectangle at
    % each position

    6 index exch {
    2 index 5 index 3 index {
        % Stack now: width height string y1 y2 x y

        gsave
        1 index exch translate
        5 index 5 index true matrix tmpstip imagemask
        grestore
    } for
    pop
    } for
    pop pop pop pop pop
} bind def

% -- AdjustColor --
% Given a color value already set for output by the caller, adjusts
% that value to a grayscale or mono value if requested by the CL
% variable.

/AdjustColor {
    CL 2 lt {
    currentgray
    CL 0 eq {
        .5 lt {0} {1} ifelse
    } if
    setgray
    } if
} bind def

% x y strings spacing xoffset yoffset justify stipple DrawText --
% This procedure does all of the real work of drawing text.  The
% color and font must already have been set by the caller, and the
% following arguments must be on the stack:
%
% x, y -    Coordinates at which to draw text.
% strings - An array of strings, one for each line of the text item,
%       in order from top to bottom.
% spacing - Spacing between lines.
% xoffset - Horizontal offset for text bbox relative to x and y: 0 for
%       nw/w/sw anchor, -0.5 for n/center/s, and -1.0 for ne/e/se.
% yoffset - Vertical offset for text bbox relative to x and y: 0 for
%       nw/n/ne anchor, +0.5 for w/center/e, and +1.0 for sw/s/se.
% justify - 0 for left justification, 0.5 for center, 1 for right justify.
% stipple - Boolean value indicating whether or not text is to be
%       drawn in stippled fashion.  If text is stippled,
%       procedure StippleText must have been defined to call
%       StippleFill in the right way.
%
% Also, when this procedure is invoked, the color and font must already
% have been set for the text.

/DrawText {
    /stipple exch def
    /justify exch def
    /yoffset exch def
    /xoffset exch def
    /spacing exch def
    /strings exch def

    % First scan through all of the text to find the widest line.

    /lineLength 0 def
    strings {
    cstringwidth pop
    dup lineLength gt {/lineLength exch def} {pop} ifelse
    newpath
    } forall

    % Compute the baseline offset and the actual font height.

    0 0 moveto (TXygqPZ) false charpath
    pathbbox dup /baseline exch def
    exch pop exch sub /height exch def pop
    newpath

    % Translate coordinates first so that the origin is at the upper-left
    % corner of the text's bounding box. Remember that x and y for
    % positioning are still on the stack.

    translate
    lineLength xoffset mul
    strings length 1 sub spacing mul height add yoffset mul translate

    % Now use the baseline and justification information to translate so
    % that the origin is at the baseline and positioning point for the
    % first line of text.

    justify lineLength mul baseline neg translate

    % Iterate over each of the lines to output it.  For each line,
    % compute its width again so it can be properly justified, then
    % display it.

    strings {
    dup cstringwidth pop
    justify neg mul 0 moveto
    stipple {


        % The text is stippled, so turn it into a path and print
        % by calling StippledText, which in turn calls StippleFill.
        % Unfortunately, many Postscript interpreters will get
        % overflow errors if we try to do the whole string at
        % once, so do it a character at a time.

        gsave
        /char (X) def
        {
        dup type /stringtype eq {
            % This segment is a string.
            {
                char 0 3 -1 roll put
                currentpoint
                gsave
                char true charpath clip StippleText
                grestore
                char stringwidth translate
                moveto
            } forall
        } {
            % This segment is glyph name
            % Temporary override
            currentfont /Encoding get exch 1 exch put
            currentpoint
            gsave (\001) true charpath clip StippleText
            grestore
                (\001) stringwidth translate
            moveto
        } ifelse
        } forall
        grestore 
    } {cstringshow} ifelse
    0 spacing neg translate
    } forall
} bind def

%%EndProlog
%%BeginSetup
/CL 2 def
%%EndSetup

%%Page: 1 1
save
306.0 396.0 translate
1.001 1.001 scale
0 0 translate
0 1 moveto 1 1 lineto 1 0 lineto 0 0 lineto closepath clip newpath
restore showpage

%%Trailer
end
%%EOF

Answer 1

Ваша программа PostScript заявляет, что она совместима с EPS:

%!PS-Adobe-3.0 EPSF-3.0

, но не содержит комментарий %% BoundingBox, который недопустим для EPS и серьезно запутает любого интерпретатора, который пытается рассматривать его как EPS.

Часть программы, которая фактически выполняет что-либо (в отличие от определения функциональности), выглядит так:

save
306.0 396.0 translate
1.001 1.001 scale
0 0 translate
0 1 moveto 1 1 lineto 1 0 lineto 0 0 lineto closepath clip newpath
restore showpage

Таким образом, сохраняя текущее состояние, перемещается начало координат (0,0 ) от нижнего левого края носителя до 306, 306. Поэтому все последующие операции по координации начнутся в этом месте на носителе. Он масштабирует CTM почти точно на 1. Преобразует источник снова, но на этот раз в 0,0, поэтому он не имеет никакого эффекта (нет, он не перемещает его назад в нижний левый угол, эти операции являются кумулятивными ).

Затем он создает квадрат 1 контура пути и делает его областью обрезки. Все последующие операции рисования, которые ie за пределами этой области будут вырезаны, а не прорисованы.

Затем он восстанавливает состояние до состояния в начале программы.

Наконец, оно отображает содержимое страницы.

Как вы могли заметить, на самом деле он вообще ничего не рисует. Так что в программе нет ничего плохого, она просто бессмысленная: -)

Вам нужно go вернуться к авторам программы и выяснить у них, почему она генерирует PostScritp, который ничего не рисует.