| 1 | %%BeginProlog |
| 2 | 50 dict begin |
| 3 | |
| 4 | % This is a standard prolog for Postscript generated by Tk's canvas |
| 5 | % widget. |
| 6 | % RCS: @(#) $Id: prolog.ps,v 1.2 1999/04/16 01:51:09 stanton Exp $ |
| 7 | |
| 8 | % The definitions below just define all of the variables used in |
| 9 | % any of the procedures here. This is needed for obscure reasons |
| 10 | % explained on p. 716 of the Postscript manual (Section H.2.7, |
| 11 | % "Initializing Variables," in the section on Encapsulated Postscript). |
| 12 | |
| 13 | /baseline 0 def |
| 14 | /stipimage 0 def |
| 15 | /height 0 def |
| 16 | /justify 0 def |
| 17 | /lineLength 0 def |
| 18 | /spacing 0 def |
| 19 | /stipple 0 def |
| 20 | /strings 0 def |
| 21 | /xoffset 0 def |
| 22 | /yoffset 0 def |
| 23 | /tmpstip null def |
| 24 | |
| 25 | % Define the array ISOLatin1Encoding (which specifies how characters are |
| 26 | % encoded for ISO-8859-1 fonts), if it isn't already present (Postscript |
| 27 | % level 2 is supposed to define it, but level 1 doesn't). |
| 28 | |
| 29 | systemdict /ISOLatin1Encoding known not { |
| 30 | /ISOLatin1Encoding [ |
| 31 | /space /space /space /space /space /space /space /space |
| 32 | /space /space /space /space /space /space /space /space |
| 33 | /space /space /space /space /space /space /space /space |
| 34 | /space /space /space /space /space /space /space /space |
| 35 | /space /exclam /quotedbl /numbersign /dollar /percent /ampersand |
| 36 | /quoteright |
| 37 | /parenleft /parenright /asterisk /plus /comma /minus /period /slash |
| 38 | /zero /one /two /three /four /five /six /seven |
| 39 | /eight /nine /colon /semicolon /less /equal /greater /question |
| 40 | /at /A /B /C /D /E /F /G |
| 41 | /H /I /J /K /L /M /N /O |
| 42 | /P /Q /R /S /T /U /V /W |
| 43 | /X /Y /Z /bracketleft /backslash /bracketright /asciicircum /underscore |
| 44 | /quoteleft /a /b /c /d /e /f /g |
| 45 | /h /i /j /k /l /m /n /o |
| 46 | /p /q /r /s /t /u /v /w |
| 47 | /x /y /z /braceleft /bar /braceright /asciitilde /space |
| 48 | /space /space /space /space /space /space /space /space |
| 49 | /space /space /space /space /space /space /space /space |
| 50 | /dotlessi /grave /acute /circumflex /tilde /macron /breve /dotaccent |
| 51 | /dieresis /space /ring /cedilla /space /hungarumlaut /ogonek /caron |
| 52 | /space /exclamdown /cent /sterling /currency /yen /brokenbar /section |
| 53 | /dieresis /copyright /ordfeminine /guillemotleft /logicalnot /hyphen |
| 54 | /registered /macron |
| 55 | /degree /plusminus /twosuperior /threesuperior /acute /mu /paragraph |
| 56 | /periodcentered |
| 57 | /cedillar /onesuperior /ordmasculine /guillemotright /onequarter |
| 58 | /onehalf /threequarters /questiondown |
| 59 | /Agrave /Aacute /Acircumflex /Atilde /Adieresis /Aring /AE /Ccedilla |
| 60 | /Egrave /Eacute /Ecircumflex /Edieresis /Igrave /Iacute /Icircumflex |
| 61 | /Idieresis |
| 62 | /Eth /Ntilde /Ograve /Oacute /Ocircumflex /Otilde /Odieresis /multiply |
| 63 | /Oslash /Ugrave /Uacute /Ucircumflex /Udieresis /Yacute /Thorn |
| 64 | /germandbls |
| 65 | /agrave /aacute /acircumflex /atilde /adieresis /aring /ae /ccedilla |
| 66 | /egrave /eacute /ecircumflex /edieresis /igrave /iacute /icircumflex |
| 67 | /idieresis |
| 68 | /eth /ntilde /ograve /oacute /ocircumflex /otilde /odieresis /divide |
| 69 | /oslash /ugrave /uacute /ucircumflex /udieresis /yacute /thorn |
| 70 | /ydieresis |
| 71 | ] def |
| 72 | } if |
| 73 | |
| 74 | % font ISOEncode font |
| 75 | % This procedure changes the encoding of a font from the default |
| 76 | % Postscript encoding to ISOLatin1. It's typically invoked just |
| 77 | % before invoking "setfont". The body of this procedure comes from |
| 78 | % Section 5.6.1 of the Postscript book. |
| 79 | |
| 80 | /ISOEncode { |
| 81 | dup length dict begin |
| 82 | {1 index /FID ne {def} {pop pop} ifelse} forall |
| 83 | /Encoding ISOLatin1Encoding def |
| 84 | currentdict |
| 85 | end |
| 86 | |
| 87 | % I'm not sure why it's necessary to use "definefont" on this new |
| 88 | % font, but it seems to be important; just use the name "Temporary" |
| 89 | % for the font. |
| 90 | |
| 91 | /Temporary exch definefont |
| 92 | } bind def |
| 93 | |
| 94 | % StrokeClip |
| 95 | % |
| 96 | % This procedure converts the current path into a clip area under |
| 97 | % the assumption of stroking. It's a bit tricky because some Postscript |
| 98 | % interpreters get errors during strokepath for dashed lines. If |
| 99 | % this happens then turn off dashes and try again. |
| 100 | |
| 101 | /StrokeClip { |
| 102 | {strokepath} stopped { |
| 103 | (This Postscript printer gets limitcheck overflows when) = |
| 104 | (stippling dashed lines; lines will be printed solid instead.) = |
| 105 | [] 0 setdash strokepath} if |
| 106 | clip |
| 107 | } bind def |
| 108 | |
| 109 | % desiredSize EvenPixels closestSize |
| 110 | % |
| 111 | % The procedure below is used for stippling. Given the optimal size |
| 112 | % of a dot in a stipple pattern in the current user coordinate system, |
| 113 | % compute the closest size that is an exact multiple of the device's |
| 114 | % pixel size. This allows stipple patterns to be displayed without |
| 115 | % aliasing effects. |
| 116 | |
| 117 | /EvenPixels { |
| 118 | % Compute exact number of device pixels per stipple dot. |
| 119 | dup 0 matrix currentmatrix dtransform |
| 120 | dup mul exch dup mul add sqrt |
| 121 | |
| 122 | % Round to an integer, make sure the number is at least 1, and compute |
| 123 | % user coord distance corresponding to this. |
| 124 | dup round dup 1 lt {pop 1} if |
| 125 | exch div mul |
| 126 | } bind def |
| 127 | |
| 128 | % width height string StippleFill -- |
| 129 | % |
| 130 | % Given a path already set up and a clipping region generated from |
| 131 | % it, this procedure will fill the clipping region with a stipple |
| 132 | % pattern. "String" contains a proper image description of the |
| 133 | % stipple pattern and "width" and "height" give its dimensions. Each |
| 134 | % stipple dot is assumed to be about one unit across in the current |
| 135 | % user coordinate system. This procedure trashes the graphics state. |
| 136 | |
| 137 | /StippleFill { |
| 138 | % The following code is needed to work around a NeWSprint bug. |
| 139 | |
| 140 | /tmpstip 1 index def |
| 141 | |
| 142 | % Change the scaling so that one user unit in user coordinates |
| 143 | % corresponds to the size of one stipple dot. |
| 144 | 1 EvenPixels dup scale |
| 145 | |
| 146 | % Compute the bounding box occupied by the path (which is now |
| 147 | % the clipping region), and round the lower coordinates down |
| 148 | % to the nearest starting point for the stipple pattern. Be |
| 149 | % careful about negative numbers, since the rounding works |
| 150 | % differently on them. |
| 151 | |
| 152 | pathbbox |
| 153 | 4 2 roll |
| 154 | 5 index div dup 0 lt {1 sub} if cvi 5 index mul 4 1 roll |
| 155 | 6 index div dup 0 lt {1 sub} if cvi 6 index mul 3 2 roll |
| 156 | |
| 157 | % Stack now: width height string y1 y2 x1 x2 |
| 158 | % Below is a doubly-nested for loop to iterate across this area |
| 159 | % in units of the stipple pattern size, going up columns then |
| 160 | % across rows, blasting out a stipple-pattern-sized rectangle at |
| 161 | % each position |
| 162 | |
| 163 | 6 index exch { |
| 164 | 2 index 5 index 3 index { |
| 165 | % Stack now: width height string y1 y2 x y |
| 166 | |
| 167 | gsave |
| 168 | 1 index exch translate |
| 169 | 5 index 5 index true matrix tmpstip imagemask |
| 170 | grestore |
| 171 | } for |
| 172 | pop |
| 173 | } for |
| 174 | pop pop pop pop pop |
| 175 | } bind def |
| 176 | |
| 177 | % -- AdjustColor -- |
| 178 | % Given a color value already set for output by the caller, adjusts |
| 179 | % that value to a grayscale or mono value if requested by the CL |
| 180 | % variable. |
| 181 | |
| 182 | /AdjustColor { |
| 183 | CL 2 lt { |
| 184 | currentgray |
| 185 | CL 0 eq { |
| 186 | .5 lt {0} {1} ifelse |
| 187 | } if |
| 188 | setgray |
| 189 | } if |
| 190 | } bind def |
| 191 | |
| 192 | % x y strings spacing xoffset yoffset justify stipple DrawText -- |
| 193 | % This procedure does all of the real work of drawing text. The |
| 194 | % color and font must already have been set by the caller, and the |
| 195 | % following arguments must be on the stack: |
| 196 | % |
| 197 | % x, y - Coordinates at which to draw text. |
| 198 | % strings - An array of strings, one for each line of the text item, |
| 199 | % in order from top to bottom. |
| 200 | % spacing - Spacing between lines. |
| 201 | % xoffset - Horizontal offset for text bbox relative to x and y: 0 for |
| 202 | % nw/w/sw anchor, -0.5 for n/center/s, and -1.0 for ne/e/se. |
| 203 | % yoffset - Vertical offset for text bbox relative to x and y: 0 for |
| 204 | % nw/n/ne anchor, +0.5 for w/center/e, and +1.0 for sw/s/se. |
| 205 | % justify - 0 for left justification, 0.5 for center, 1 for right justify. |
| 206 | % stipple - Boolean value indicating whether or not text is to be |
| 207 | % drawn in stippled fashion. If text is stippled, |
| 208 | % procedure StippleText must have been defined to call |
| 209 | % StippleFill in the right way. |
| 210 | % |
| 211 | % Also, when this procedure is invoked, the color and font must already |
| 212 | % have been set for the text. |
| 213 | |
| 214 | /DrawText { |
| 215 | /stipple exch def |
| 216 | /justify exch def |
| 217 | /yoffset exch def |
| 218 | /xoffset exch def |
| 219 | /spacing exch def |
| 220 | /strings exch def |
| 221 | |
| 222 | % First scan through all of the text to find the widest line. |
| 223 | |
| 224 | /lineLength 0 def |
| 225 | strings { |
| 226 | stringwidth pop |
| 227 | dup lineLength gt {/lineLength exch def} {pop} ifelse |
| 228 | newpath |
| 229 | } forall |
| 230 | |
| 231 | % Compute the baseline offset and the actual font height. |
| 232 | |
| 233 | 0 0 moveto (TXygqPZ) false charpath |
| 234 | pathbbox dup /baseline exch def |
| 235 | exch pop exch sub /height exch def pop |
| 236 | newpath |
| 237 | |
| 238 | % Translate coordinates first so that the origin is at the upper-left |
| 239 | % corner of the text's bounding box. Remember that x and y for |
| 240 | % positioning are still on the stack. |
| 241 | |
| 242 | translate |
| 243 | lineLength xoffset mul |
| 244 | strings length 1 sub spacing mul height add yoffset mul translate |
| 245 | |
| 246 | % Now use the baseline and justification information to translate so |
| 247 | % that the origin is at the baseline and positioning point for the |
| 248 | % first line of text. |
| 249 | |
| 250 | justify lineLength mul baseline neg translate |
| 251 | |
| 252 | % Iterate over each of the lines to output it. For each line, |
| 253 | % compute its width again so it can be properly justified, then |
| 254 | % display it. |
| 255 | |
| 256 | strings { |
| 257 | dup stringwidth pop |
| 258 | justify neg mul 0 moveto |
| 259 | stipple { |
| 260 | |
| 261 | % The text is stippled, so turn it into a path and print |
| 262 | % by calling StippledText, which in turn calls StippleFill. |
| 263 | % Unfortunately, many Postscript interpreters will get |
| 264 | % overflow errors if we try to do the whole string at |
| 265 | % once, so do it a character at a time. |
| 266 | |
| 267 | gsave |
| 268 | /char (X) def |
| 269 | { |
| 270 | char 0 3 -1 roll put |
| 271 | currentpoint |
| 272 | gsave |
| 273 | char true charpath clip StippleText |
| 274 | grestore |
| 275 | char stringwidth translate |
| 276 | moveto |
| 277 | } forall |
| 278 | grestore |
| 279 | } {show} ifelse |
| 280 | 0 spacing neg translate |
| 281 | } forall |
| 282 | } bind def |
| 283 | |
| 284 | %%EndProlog |