| 1 | '\" |
| 2 | '\" Copyright (c) 1990-1991 The Regents of the University of California. |
| 3 | '\" Copyright (c) 1994-1998 Sun Microsystems, Inc. |
| 4 | '\" |
| 5 | '\" See the file "license.terms" for information on usage and redistribution |
| 6 | '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. |
| 7 | '\" |
| 8 | '\" RCS: @(#) $Id: GetColor.3,v 1.4 2002/08/05 04:30:38 dgp Exp $ |
| 9 | '\" |
| 10 | '\" The definitions below are for supplemental macros used in Tcl/Tk |
| 11 | '\" manual entries. |
| 12 | '\" |
| 13 | '\" .AP type name in/out ?indent? |
| 14 | '\" Start paragraph describing an argument to a library procedure. |
| 15 | '\" type is type of argument (int, etc.), in/out is either "in", "out", |
| 16 | '\" or "in/out" to describe whether procedure reads or modifies arg, |
| 17 | '\" and indent is equivalent to second arg of .IP (shouldn't ever be |
| 18 | '\" needed; use .AS below instead) |
| 19 | '\" |
| 20 | '\" .AS ?type? ?name? |
| 21 | '\" Give maximum sizes of arguments for setting tab stops. Type and |
| 22 | '\" name are examples of largest possible arguments that will be passed |
| 23 | '\" to .AP later. If args are omitted, default tab stops are used. |
| 24 | '\" |
| 25 | '\" .BS |
| 26 | '\" Start box enclosure. From here until next .BE, everything will be |
| 27 | '\" enclosed in one large box. |
| 28 | '\" |
| 29 | '\" .BE |
| 30 | '\" End of box enclosure. |
| 31 | '\" |
| 32 | '\" .CS |
| 33 | '\" Begin code excerpt. |
| 34 | '\" |
| 35 | '\" .CE |
| 36 | '\" End code excerpt. |
| 37 | '\" |
| 38 | '\" .VS ?version? ?br? |
| 39 | '\" Begin vertical sidebar, for use in marking newly-changed parts |
| 40 | '\" of man pages. The first argument is ignored and used for recording |
| 41 | '\" the version when the .VS was added, so that the sidebars can be |
| 42 | '\" found and removed when they reach a certain age. If another argument |
| 43 | '\" is present, then a line break is forced before starting the sidebar. |
| 44 | '\" |
| 45 | '\" .VE |
| 46 | '\" End of vertical sidebar. |
| 47 | '\" |
| 48 | '\" .DS |
| 49 | '\" Begin an indented unfilled display. |
| 50 | '\" |
| 51 | '\" .DE |
| 52 | '\" End of indented unfilled display. |
| 53 | '\" |
| 54 | '\" .SO |
| 55 | '\" Start of list of standard options for a Tk widget. The |
| 56 | '\" options follow on successive lines, in four columns separated |
| 57 | '\" by tabs. |
| 58 | '\" |
| 59 | '\" .SE |
| 60 | '\" End of list of standard options for a Tk widget. |
| 61 | '\" |
| 62 | '\" .OP cmdName dbName dbClass |
| 63 | '\" Start of description of a specific option. cmdName gives the |
| 64 | '\" option's name as specified in the class command, dbName gives |
| 65 | '\" the option's name in the option database, and dbClass gives |
| 66 | '\" the option's class in the option database. |
| 67 | '\" |
| 68 | '\" .UL arg1 arg2 |
| 69 | '\" Print arg1 underlined, then print arg2 normally. |
| 70 | '\" |
| 71 | '\" RCS: @(#) $Id: man.macros,v 1.4 2000/08/25 06:18:32 ericm Exp $ |
| 72 | '\" |
| 73 | '\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages. |
| 74 | .if t .wh -1.3i ^B |
| 75 | .nr ^l \n(.l |
| 76 | .ad b |
| 77 | '\" # Start an argument description |
| 78 | .de AP |
| 79 | .ie !"\\$4"" .TP \\$4 |
| 80 | .el \{\ |
| 81 | . ie !"\\$2"" .TP \\n()Cu |
| 82 | . el .TP 15 |
| 83 | .\} |
| 84 | .ta \\n()Au \\n()Bu |
| 85 | .ie !"\\$3"" \{\ |
| 86 | \&\\$1 \\fI\\$2\\fP (\\$3) |
| 87 | .\".b |
| 88 | .\} |
| 89 | .el \{\ |
| 90 | .br |
| 91 | .ie !"\\$2"" \{\ |
| 92 | \&\\$1 \\fI\\$2\\fP |
| 93 | .\} |
| 94 | .el \{\ |
| 95 | \&\\fI\\$1\\fP |
| 96 | .\} |
| 97 | .\} |
| 98 | .. |
| 99 | '\" # define tabbing values for .AP |
| 100 | .de AS |
| 101 | .nr )A 10n |
| 102 | .if !"\\$1"" .nr )A \\w'\\$1'u+3n |
| 103 | .nr )B \\n()Au+15n |
| 104 | .\" |
| 105 | .if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n |
| 106 | .nr )C \\n()Bu+\\w'(in/out)'u+2n |
| 107 | .. |
| 108 | .AS Tcl_Interp Tcl_CreateInterp in/out |
| 109 | '\" # BS - start boxed text |
| 110 | '\" # ^y = starting y location |
| 111 | '\" # ^b = 1 |
| 112 | .de BS |
| 113 | .br |
| 114 | .mk ^y |
| 115 | .nr ^b 1u |
| 116 | .if n .nf |
| 117 | .if n .ti 0 |
| 118 | .if n \l'\\n(.lu\(ul' |
| 119 | .if n .fi |
| 120 | .. |
| 121 | '\" # BE - end boxed text (draw box now) |
| 122 | .de BE |
| 123 | .nf |
| 124 | .ti 0 |
| 125 | .mk ^t |
| 126 | .ie n \l'\\n(^lu\(ul' |
| 127 | .el \{\ |
| 128 | .\" Draw four-sided box normally, but don't draw top of |
| 129 | .\" box if the box started on an earlier page. |
| 130 | .ie !\\n(^b-1 \{\ |
| 131 | \h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul' |
| 132 | .\} |
| 133 | .el \}\ |
| 134 | \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul' |
| 135 | .\} |
| 136 | .\} |
| 137 | .fi |
| 138 | .br |
| 139 | .nr ^b 0 |
| 140 | .. |
| 141 | '\" # VS - start vertical sidebar |
| 142 | '\" # ^Y = starting y location |
| 143 | '\" # ^v = 1 (for troff; for nroff this doesn't matter) |
| 144 | .de VS |
| 145 | .if !"\\$2"" .br |
| 146 | .mk ^Y |
| 147 | .ie n 'mc \s12\(br\s0 |
| 148 | .el .nr ^v 1u |
| 149 | .. |
| 150 | '\" # VE - end of vertical sidebar |
| 151 | .de VE |
| 152 | .ie n 'mc |
| 153 | .el \{\ |
| 154 | .ev 2 |
| 155 | .nf |
| 156 | .ti 0 |
| 157 | .mk ^t |
| 158 | \h'|\\n(^lu+3n'\L'|\\n(^Yu-1v\(bv'\v'\\n(^tu+1v-\\n(^Yu'\h'-|\\n(^lu+3n' |
| 159 | .sp -1 |
| 160 | .fi |
| 161 | .ev |
| 162 | .\} |
| 163 | .nr ^v 0 |
| 164 | .. |
| 165 | '\" # Special macro to handle page bottom: finish off current |
| 166 | '\" # box/sidebar if in box/sidebar mode, then invoked standard |
| 167 | '\" # page bottom macro. |
| 168 | .de ^B |
| 169 | .ev 2 |
| 170 | 'ti 0 |
| 171 | 'nf |
| 172 | .mk ^t |
| 173 | .if \\n(^b \{\ |
| 174 | .\" Draw three-sided box if this is the box's first page, |
| 175 | .\" draw two sides but no top otherwise. |
| 176 | .ie !\\n(^b-1 \h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c |
| 177 | .el \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c |
| 178 | .\} |
| 179 | .if \\n(^v \{\ |
| 180 | .nr ^x \\n(^tu+1v-\\n(^Yu |
| 181 | \kx\h'-\\nxu'\h'|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'|0u'\c |
| 182 | .\} |
| 183 | .bp |
| 184 | 'fi |
| 185 | .ev |
| 186 | .if \\n(^b \{\ |
| 187 | .mk ^y |
| 188 | .nr ^b 2 |
| 189 | .\} |
| 190 | .if \\n(^v \{\ |
| 191 | .mk ^Y |
| 192 | .\} |
| 193 | .. |
| 194 | '\" # DS - begin display |
| 195 | .de DS |
| 196 | .RS |
| 197 | .nf |
| 198 | .sp |
| 199 | .. |
| 200 | '\" # DE - end display |
| 201 | .de DE |
| 202 | .fi |
| 203 | .RE |
| 204 | .sp |
| 205 | .. |
| 206 | '\" # SO - start of list of standard options |
| 207 | .de SO |
| 208 | .SH "STANDARD OPTIONS" |
| 209 | .LP |
| 210 | .nf |
| 211 | .ta 5.5c 11c |
| 212 | .ft B |
| 213 | .. |
| 214 | '\" # SE - end of list of standard options |
| 215 | .de SE |
| 216 | .fi |
| 217 | .ft R |
| 218 | .LP |
| 219 | See the \\fBoptions\\fR manual entry for details on the standard options. |
| 220 | .. |
| 221 | '\" # OP - start of full description for a single option |
| 222 | .de OP |
| 223 | .LP |
| 224 | .nf |
| 225 | .ta 4c |
| 226 | Command-Line Name: \\fB\\$1\\fR |
| 227 | Database Name: \\fB\\$2\\fR |
| 228 | Database Class: \\fB\\$3\\fR |
| 229 | .fi |
| 230 | .IP |
| 231 | .. |
| 232 | '\" # CS - begin code excerpt |
| 233 | .de CS |
| 234 | .RS |
| 235 | .nf |
| 236 | .ta .25i .5i .75i 1i |
| 237 | .. |
| 238 | '\" # CE - end code excerpt |
| 239 | .de CE |
| 240 | .fi |
| 241 | .RE |
| 242 | .. |
| 243 | .de UL |
| 244 | \\$1\l'|0\(ul'\\$2 |
| 245 | .. |
| 246 | .TH Tk_AllocColorFromObj 3 8.1 Tk "Tk Library Procedures" |
| 247 | .BS |
| 248 | .SH NAME |
| 249 | Tk_AllocColorFromObj, Tk_GetColor, Tk_GetColorFromObj, Tk_GetColorByValue, Tk_NameOfColor, Tk_FreeColorFromObj, Tk_FreeColor \- maintain database of colors |
| 250 | .SH SYNOPSIS |
| 251 | .nf |
| 252 | \fB#include <tk.h>\fR |
| 253 | .VS 8.1 |
| 254 | .sp |
| 255 | XColor * |
| 256 | \fBTk_AllocColorFromObj(\fIinterp, tkwin, objPtr\fB)\fR |
| 257 | .sp |
| 258 | XColor * |
| 259 | \fBTk_GetColor(\fIinterp, tkwin, name\fB)\fR |
| 260 | .sp |
| 261 | XColor * |
| 262 | \fBTk_GetColorFromObj(\fItkwin, objPtr\fB)\fR |
| 263 | .VE |
| 264 | .sp |
| 265 | XColor * |
| 266 | \fBTk_GetColorByValue(\fItkwin, prefPtr\fB)\fR |
| 267 | .sp |
| 268 | CONST char * |
| 269 | \fBTk_NameOfColor(\fIcolorPtr\fB)\fR |
| 270 | .sp |
| 271 | GC |
| 272 | \fBTk_GCForColor(\fIcolorPtr, drawable\fB)\fR |
| 273 | .sp |
| 274 | .VS 8.1 |
| 275 | \fBTk_FreeColorFromObj(\fItkwin, objPtr\fB)\fR |
| 276 | .VE |
| 277 | .sp |
| 278 | \fBTk_FreeColor(\fIcolorPtr\fB)\fR |
| 279 | .SH ARGUMENTS |
| 280 | .AS "Tcl_Interp" *colorPtr |
| 281 | .AP Tcl_Interp *interp in |
| 282 | Interpreter to use for error reporting. |
| 283 | .AP Tk_Window tkwin in |
| 284 | Token for window in which color will be used. |
| 285 | .VS 8.1 br |
| 286 | .AP Tcl_Obj *objPtr in/out |
| 287 | String value describes desired color; internal rep will be |
| 288 | modified to cache pointer to corresponding (XColor *). |
| 289 | .AP char *name in |
| 290 | Same as \fIobjPtr\fR except description of color is passed as a string and |
| 291 | resulting (XColor *) isn't cached. |
| 292 | .VE |
| 293 | .AP XColor *prefPtr in |
| 294 | Indicates red, green, and blue intensities of desired |
| 295 | color. |
| 296 | .AP XColor *colorPtr in |
| 297 | Pointer to X color information. Must have been allocated by previous |
| 298 | call to \fBTk_AllocColorFromObj\fR, \fBTk_GetColor\fR or |
| 299 | \fBTk_GetColorByValue\fR, except when passed to \fBTk_NameOfColor\fR. |
| 300 | .AP Drawable drawable in |
| 301 | Drawable in which the result graphics context will be used. Must have |
| 302 | same screen and depth as the window for which the color was allocated. |
| 303 | .BE |
| 304 | |
| 305 | .SH DESCRIPTION |
| 306 | .VS 8.1 |
| 307 | .PP |
| 308 | These procedures manage the colors being used by a Tk application. |
| 309 | They allow colors to be shared whenever possible, so that colormap |
| 310 | space is preserved, and they pick closest available colors when |
| 311 | colormap space is exhausted. |
| 312 | .PP |
| 313 | Given a textual description of a color, \fBTk_AllocColorFromObj\fR |
| 314 | locates a pixel value that may be used to render the color |
| 315 | in a particular window. The desired color is specified with an |
| 316 | object whose string value must have one of the following forms: |
| 317 | .VE |
| 318 | .TP 20 |
| 319 | \fIcolorname\fR |
| 320 | Any of the valid textual names for a color defined in the |
| 321 | server's color database file, such as \fBred\fR or \fBPeachPuff\fR. |
| 322 | .TP 20 |
| 323 | \fB#\fIRGB\fR |
| 324 | .TP 20 |
| 325 | \fB#\fIRRGGBB\fR |
| 326 | .TP 20 |
| 327 | \fB#\fIRRRGGGBBB\fR |
| 328 | .TP 20 |
| 329 | \fB#\fIRRRRGGGGBBBB\fR |
| 330 | A numeric specification of the red, green, and blue intensities |
| 331 | to use to display the color. Each \fIR\fR, \fIG\fR, or \fIB\fR |
| 332 | represents a single hexadecimal digit. The four forms permit |
| 333 | colors to be specified with 4-bit, 8-bit, 12-bit or 16-bit values. |
| 334 | When fewer than 16 bits are provided for each color, they represent |
| 335 | the most significant bits of the color. For example, #3a7 is the |
| 336 | same as #3000a0007000. |
| 337 | .PP |
| 338 | .VS 8.1 |
| 339 | \fBTk_AllocColorFromObj\fR returns a pointer to |
| 340 | an XColor structure; the structure indicates the exact intensities of |
| 341 | the allocated color (which may differ slightly from those requested, |
| 342 | depending on the limitations of the screen) and a pixel value |
| 343 | that may be used to draw with the color in \fItkwin\fR. |
| 344 | If an error occurs in \fBTk_AllocColorFromObj\fR (such as an unknown |
| 345 | color name) then NULL is returned and an error message is stored in |
| 346 | \fIinterp\fR's result if \fIinterp\fR isn't NULL. |
| 347 | If the colormap for \fItkwin\fR is full, \fBTk_AllocColorFromObj\fR |
| 348 | will use the closest existing color in the colormap. |
| 349 | \fBTk_AllocColorFromObj\fR caches information about |
| 350 | the return value in \fIobjPtr\fR, which speeds up future calls to procedures |
| 351 | such as \fBTk_AllocColorFromObj\fR and \fBTk_GetColorFromObj\fR. |
| 352 | .PP |
| 353 | \fBTk_GetColor\fR is identical to \fBTk_AllocColorFromObj\fR except |
| 354 | that the description of the color is specified with a string instead |
| 355 | of an object. This prevents \fBTk_GetColor\fR from caching the |
| 356 | return value, so \fBTk_GetColor\fR is less efficient than |
| 357 | \fBTk_AllocColorFromObj\fR. |
| 358 | .PP |
| 359 | \fBTk_GetColorFromObj\fR returns the token for an existing color, given |
| 360 | the window and description used to create the color. |
| 361 | \fBTk_GetColorFromObj\fR doesn't actually create the color; the color |
| 362 | must already have been created with a previous call to |
| 363 | \fBTk_AllocColorFromObj\fR or \fBTk_GetColor\fR. The return |
| 364 | value is cached in \fIobjPtr\fR, which speeds up |
| 365 | future calls to \fBTk_GetColorFromObj\fR with the same \fIobjPtr\fR |
| 366 | and \fItkwin\fR. |
| 367 | .VE |
| 368 | .PP |
| 369 | \fBTk_GetColorByValue\fR is similar to \fBTk_GetColor\fR except that |
| 370 | the desired color is indicated with the \fIred\fR, \fIgreen\fR, and |
| 371 | \fIblue\fR fields of the structure pointed to by \fIcolorPtr\fR. |
| 372 | .PP |
| 373 | This package maintains a database |
| 374 | of all the colors currently in use. |
| 375 | If the same color is requested multiple times from |
| 376 | \fBTk_GetColor\fR or \fBTk_AllocColorFromObj\fR (e.g. by different |
| 377 | windows), or if the |
| 378 | same intensities are requested multiple times from |
| 379 | \fBTk_GetColorByValue\fR, then existing pixel values will |
| 380 | be re-used. Re-using an existing pixel avoids any interaction |
| 381 | with the window server, which makes the allocation much more |
| 382 | efficient. These procedures also provide a portable interface that |
| 383 | works across all platforms. For this reason, you should generally use |
| 384 | \fBTk_AllocColorFromObj\fR, \fBTk_GetColor\fR, or \fBTk_GetColorByValue\fR |
| 385 | instead of lower level procedures like \fBXAllocColor\fR. |
| 386 | .PP |
| 387 | Since different calls to this package |
| 388 | may return the same shared |
| 389 | pixel value, callers should never change the color of a pixel |
| 390 | returned by the procedures. |
| 391 | If you need to change a color value dynamically, you should use |
| 392 | \fBXAllocColorCells\fR to allocate the pixel value for the color. |
| 393 | .PP |
| 394 | The procedure \fBTk_NameOfColor\fR is roughly the inverse of |
| 395 | \fBTk_GetColor\fR. If its \fIcolorPtr\fR argument was created |
| 396 | by \fBTk_AllocColorFromObj\fR or \fBTk_GetColor\fR then the return value |
| 397 | is the string that was used to create the |
| 398 | color. If \fIcolorPtr\fR was created by a call to \fBTk_GetColorByValue\fR, |
| 399 | or by any other mechanism, then the return value is a string |
| 400 | that could be passed to \fBTk_GetColor\fR to return the same |
| 401 | color. Note: the string returned by \fBTk_NameOfColor\fR is |
| 402 | only guaranteed to persist until the next call to |
| 403 | \fBTk_NameOfColor\fR. |
| 404 | .PP |
| 405 | \fBTk_GCForColor\fR returns a graphics context whose \fBforeground\fR |
| 406 | field is the pixel allocated for \fIcolorPtr\fR and whose other fields |
| 407 | all have default values. |
| 408 | This provides an easy way to do basic drawing with a color. |
| 409 | The graphics context is cached with the color and will exist only as |
| 410 | long as \fIcolorPtr\fR exists; it is freed when the last reference |
| 411 | to \fIcolorPtr\fR is freed by calling \fBTk_FreeColor\fR. |
| 412 | .PP |
| 413 | .VS 8.1 |
| 414 | When a color is no longer needed \fBTk_FreeColorFromObj\fR or |
| 415 | \fBTk_FreeColor\fR should be called to release it. |
| 416 | For \fBTk_FreeColorFromObj\fR the color to release is specified |
| 417 | with the same information used to create it; for |
| 418 | \fBTk_FreeColor\fR the color to release is specified |
| 419 | with a pointer to its XColor structure. |
| 420 | There should be exactly one call to \fBTk_FreeColorFromObj\fR |
| 421 | or \fBTk_FreeColor\fR for each call to \fBTk_AllocColorFromObj\fR, |
| 422 | \fBTk_GetColor\fR, or \fBTk_GetColorByValue\fR. |
| 423 | .VE |
| 424 | .SH KEYWORDS |
| 425 | color, intensity, object, pixel value |