1 | #! perl |
1 | #! perl |
2 | |
2 | |
3 | #:META:X_RESOURCE:%.expr:string:background expression |
3 | #:META:X_RESOURCE:%.expr:string:background expression |
4 | #:META:X_RESOURCE:%.border.:boolean:respect the terminal border |
4 | #:META:X_RESOURCE:%.border:boolean:respect the terminal border |
|
|
5 | #:META:X_RESOURCE:%.interval:seconds:minimum time between updates |
5 | |
6 | |
6 | #TODO: once, rootalign |
7 | #TODO: once, rootalign |
7 | |
8 | |
|
|
9 | =head1 NAME |
|
|
10 | |
8 | =head1 background - manage terminal background |
11 | background - manage terminal background |
9 | |
12 | |
10 | =head2 SYNOPSIS |
13 | =head1 SYNOPSIS |
11 | |
14 | |
12 | urxvt --background-expr 'background expression' |
15 | urxvt --background-expr 'background expression' |
13 | --background-border |
16 | --background-border |
|
|
17 | --background-interval seconds |
14 | |
18 | |
15 | =head2 DESCRIPTION |
19 | =head1 DESCRIPTION |
16 | |
20 | |
17 | This extension manages the terminal background by creating a picture that |
21 | This extension manages the terminal background by creating a picture that |
18 | is behind the text, replacing the normal background colour. |
22 | is behind the text, replacing the normal background colour. |
19 | |
23 | |
20 | It does so by evaluating a Perl expression that I<calculates> the image on |
24 | It does so by evaluating a Perl expression that I<calculates> the image on |
… | |
… | |
30 | |
34 | |
31 | Or specified as a X resource: |
35 | Or specified as a X resource: |
32 | |
36 | |
33 | URxvt.background-expr: scale load "/path/to/mybg.png" |
37 | URxvt.background-expr: scale load "/path/to/mybg.png" |
34 | |
38 | |
35 | =head2 THEORY OF OPERATION |
39 | =head1 THEORY OF OPERATION |
36 | |
40 | |
37 | At startup, just before the window is mapped for the first time, the |
41 | At startup, just before the window is mapped for the first time, the |
38 | expression is evaluated and must yield an image. The image is then |
42 | expression is evaluated and must yield an image. The image is then |
39 | extended as necessary to cover the whole terminal window, and is set as a |
43 | extended as necessary to cover the whole terminal window, and is set as a |
40 | background pixmap. |
44 | background pixmap. |
… | |
… | |
57 | image to the window size, so it relies on the window size and will |
61 | image to the window size, so it relies on the window size and will |
58 | be reevaluated each time it is changed, but not when it moves for |
62 | be reevaluated each time it is changed, but not when it moves for |
59 | example. That ensures that the picture always fills the terminal, even |
63 | example. That ensures that the picture always fills the terminal, even |
60 | after it's size changes. |
64 | after it's size changes. |
61 | |
65 | |
62 | =head3 EXPRESSIONS |
66 | =head2 EXPRESSIONS |
63 | |
67 | |
64 | Expressions are normal Perl expressions, in fact, they are Perl blocks - |
68 | Expressions are normal Perl expressions, in fact, they are Perl blocks - |
65 | which means you could use multiple lines and statements: |
69 | which means you could use multiple lines and statements: |
66 | |
70 | |
67 | again 3600; |
71 | again 3600; |
… | |
… | |
97 | its result becomes the argument to the C<scale> function. |
101 | its result becomes the argument to the C<scale> function. |
98 | |
102 | |
99 | Many operators also allow some parameters preceding the input image |
103 | Many operators also allow some parameters preceding the input image |
100 | that modify its behaviour. For example, C<scale> without any additional |
104 | that modify its behaviour. For example, C<scale> without any additional |
101 | arguments scales the image to size of the terminal window. If you specify |
105 | arguments scales the image to size of the terminal window. If you specify |
102 | an additional argument, it uses it as a percentage: |
106 | an additional argument, it uses it as a scale factor (multiply by 100 to |
|
|
107 | get a percentage): |
103 | |
108 | |
104 | scale 200, load "$HOME/mypic.png" |
109 | scale 2, load "$HOME/mypic.png" |
105 | |
110 | |
106 | This enlarges the image by a factor of 2 (200%). As you can see, C<scale> |
111 | This enlarges the image by a factor of 2 (200%). As you can see, C<scale> |
107 | has now two arguments, the C<200> and the C<load> expression, while |
112 | has now two arguments, the C<200> and the C<load> expression, while |
108 | C<load> only has one argument. Arguments are separated from each other by |
113 | C<load> only has one argument. Arguments are separated from each other by |
109 | commas. |
114 | commas. |
110 | |
115 | |
111 | Scale also accepts two arguments, which are then separate factors for both |
116 | Scale also accepts two arguments, which are then separate factors for both |
112 | horizontal and vertical dimensions. For example, this halves the image |
117 | horizontal and vertical dimensions. For example, this halves the image |
113 | width and doubles the image height: |
118 | width and doubles the image height: |
114 | |
119 | |
115 | scale 50, 200, load "$HOME/mypic.png" |
120 | scale 0.5, 2, load "$HOME/mypic.png" |
116 | |
121 | |
117 | Other effects than scalign are also readily available, for exmaple, you can |
122 | Other effects than scalign are also readily available, for exmaple, you can |
118 | tile the image to fill the whole window, instead of resizing it: |
123 | tile the image to fill the whole window, instead of resizing it: |
119 | |
124 | |
120 | tile load "$HOME/mypic.png" |
125 | tile load "$HOME/mypic.png" |
… | |
… | |
133 | It first takes a snapshot of the screen background image, and then |
138 | It first takes a snapshot of the screen background image, and then |
134 | moves it to the upper left corner of the screen - the result is |
139 | moves it to the upper left corner of the screen - the result is |
135 | pseudo-transparency, as the image seems to be static while the window is |
140 | pseudo-transparency, as the image seems to be static while the window is |
136 | moved around. |
141 | moved around. |
137 | |
142 | |
138 | =head3 CYCLES AND CACHING |
143 | =head2 CYCLES AND CACHING |
139 | |
144 | |
140 | As has been mentioned before, the expression might be evaluated multiple |
145 | As has been mentioned before, the expression might be evaluated multiple |
141 | times. Each time the expression is reevaluated, a new cycle is said to |
146 | times. Each time the expression is reevaluated, a new cycle is said to |
142 | have begun. Many operators cache their results till the next cycle. |
147 | have begun. Many operators cache their results till the next cycle. |
143 | |
148 | |
… | |
… | |
168 | |
173 | |
169 | Here, a path is selected randomly, and load is only called for one image, |
174 | Here, a path is selected randomly, and load is only called for one image, |
170 | so keeps only one image in memory. If, on the next evaluation, luck |
175 | so keeps only one image in memory. If, on the next evaluation, luck |
171 | decides to use the other path, then it will have to load that image again. |
176 | decides to use the other path, then it will have to load that image again. |
172 | |
177 | |
173 | =head2 REFERENCE |
178 | =head1 REFERENCE |
174 | |
179 | |
175 | =head3 COMMAND LINE SWITCHES |
180 | =head2 COMMAND LINE SWITCHES |
176 | |
181 | |
177 | =over 4 |
182 | =over 4 |
178 | |
183 | |
179 | =item --background-expr perl-expression |
184 | =item --background-expr perl-expression |
180 | |
185 | |
… | |
… | |
185 | By default, the expression creates an image that fills the full window, |
190 | By default, the expression creates an image that fills the full window, |
186 | overwriting borders and any other areas, such as the scrollbar. |
191 | overwriting borders and any other areas, such as the scrollbar. |
187 | |
192 | |
188 | Specifying this flag changes the behaviour, so that the image only |
193 | Specifying this flag changes the behaviour, so that the image only |
189 | replaces the background of the character area. |
194 | replaces the background of the character area. |
|
|
195 | |
|
|
196 | =item --background-interval seconds |
|
|
197 | |
|
|
198 | Since some operations in the underlying XRender extension can effetively |
|
|
199 | freeze your X-server for prolonged time, this extension enforces a minimum |
|
|
200 | time between updates, which is normally about 0.1 seconds. |
|
|
201 | |
|
|
202 | If you want to do updates more often, you can decrease this safety |
|
|
203 | interval with this switch. |
190 | |
204 | |
191 | =back |
205 | =back |
192 | |
206 | |
193 | =cut |
207 | =cut |
194 | |
208 | |
195 | our $HOME; |
209 | our $HOME; |
196 | our ($self, $old, $new); |
210 | our ($self, $old, $new); |
197 | our ($x, $y, $w, $h); |
211 | our ($x, $y, $w, $h); |
198 | |
212 | |
199 | # enforce at least this interval between updates |
213 | # enforce at least this interval between updates |
200 | our $MIN_INTERVAL = 1/100; |
214 | our $MIN_INTERVAL = 6/59.951; |
201 | |
215 | |
202 | { |
216 | { |
203 | package urxvt::bgdsl; # background language |
217 | package urxvt::bgdsl; # background language |
|
|
218 | |
|
|
219 | use List::Util qw(min max sum shuffle); |
204 | |
220 | |
205 | =head2 PROVIDERS/GENERATORS |
221 | =head2 PROVIDERS/GENERATORS |
206 | |
222 | |
207 | These functions provide an image, by loading it from disk, grabbing it |
223 | These functions provide an image, by loading it from disk, grabbing it |
208 | from the root screen or by simply generating it. They are used as starting |
224 | from the root screen or by simply generating it. They are used as starting |
… | |
… | |
250 | If C<$width> and C<$height> are omitted, it creates a 1x1 image, which is |
266 | If C<$width> and C<$height> are omitted, it creates a 1x1 image, which is |
251 | useful for solid backgrounds or for use in filtering effects. |
267 | useful for solid backgrounds or for use in filtering effects. |
252 | |
268 | |
253 | =cut |
269 | =cut |
254 | |
270 | |
255 | sub solid($$;$) { |
271 | sub solid($;$$) { |
256 | my $colour = pop; |
272 | my $colour = pop; |
257 | |
273 | |
258 | my $img = $self->new_img (urxvt::PictStandardARGB32, $_[0] || 1, $_[1] || 1); |
274 | my $img = $self->new_img (urxvt::PictStandardARGB32, $_[0] || 1, $_[1] || 1); |
259 | $img->fill ($colour); |
275 | $img->fill ($colour); |
260 | $img |
276 | $img |
261 | } |
277 | } |
262 | |
278 | |
|
|
279 | =item clone $img |
|
|
280 | |
|
|
281 | Returns an exact copy of the image. This is useful if you want to have |
|
|
282 | multiple copies of the same image to apply different effects to. |
|
|
283 | |
|
|
284 | =cut |
|
|
285 | |
|
|
286 | sub clone($) { |
|
|
287 | $_[0]->clone |
|
|
288 | } |
|
|
289 | |
263 | =back |
290 | =back |
264 | |
291 | |
|
|
292 | =head2 TILING MODES |
|
|
293 | |
|
|
294 | The following operators modify the tiling mode of an image, that is, the |
|
|
295 | way that pixels outside the image area are painted when the image is used. |
|
|
296 | |
|
|
297 | =over 4 |
|
|
298 | |
|
|
299 | =item tile $img |
|
|
300 | |
|
|
301 | Tiles the whole plane with the image and returns this new image - or in |
|
|
302 | other words, it returns a copy of the image in plane tiling mode. |
|
|
303 | |
|
|
304 | Example: load an image and tile it over the background, without |
|
|
305 | resizing. The C<tile> call is superfluous because C<load> already defaults |
|
|
306 | to tiling mode. |
|
|
307 | |
|
|
308 | tile load "mybg.png" |
|
|
309 | |
|
|
310 | =item mirror $img |
|
|
311 | |
|
|
312 | Similar to tile, but reflects the image each time it uses a new copy, so |
|
|
313 | that top edges always touch top edges, right edges always touch right |
|
|
314 | edges and so on (with normal tiling, left edges always touch right edges |
|
|
315 | and top always touch bottom edges). |
|
|
316 | |
|
|
317 | Example: load an image and mirror it over the background, avoiding sharp |
|
|
318 | edges at the image borders at the expense of mirroring the image itself |
|
|
319 | |
|
|
320 | mirror load "mybg.png" |
|
|
321 | |
|
|
322 | =item pad $img |
|
|
323 | |
|
|
324 | Takes an image and modifies it so that all pixels outside the image area |
|
|
325 | become transparent. This mode is most useful when you want to place an |
|
|
326 | image over another image or the background colour while leaving all |
|
|
327 | background pixels outside the image unchanged. |
|
|
328 | |
|
|
329 | Example: load an image and display it in the upper left corner. The rest |
|
|
330 | of the space is left "empty" (transparent or wahtever your compisotr does |
|
|
331 | in alpha mode, else background colour). |
|
|
332 | |
|
|
333 | pad load "mybg.png" |
|
|
334 | |
|
|
335 | =item extend $img |
|
|
336 | |
|
|
337 | Extends the image over the whole plane, using the closest pixel in the |
|
|
338 | area outside the image. This mode is mostly useful when you more complex |
|
|
339 | filtering operations and want the pixels outside the image to have the |
|
|
340 | same values as the pixels near the edge. |
|
|
341 | |
|
|
342 | Example: just for curiosity, how does this pixel extension stuff work? |
|
|
343 | |
|
|
344 | extend move 50, 50, load "mybg.png" |
|
|
345 | |
|
|
346 | =cut |
|
|
347 | |
|
|
348 | sub pad($) { |
|
|
349 | my $img = $_[0]->clone; |
|
|
350 | $img->repeat_mode (urxvt::RepeatNone); |
|
|
351 | $img |
|
|
352 | } |
|
|
353 | |
|
|
354 | sub tile($) { |
|
|
355 | my $img = $_[0]->clone; |
|
|
356 | $img->repeat_mode (urxvt::RepeatNormal); |
|
|
357 | $img |
|
|
358 | } |
|
|
359 | |
|
|
360 | sub mirror($) { |
|
|
361 | my $img = $_[0]->clone; |
|
|
362 | $img->repeat_mode (urxvt::RepeatReflect); |
|
|
363 | $img |
|
|
364 | } |
|
|
365 | |
|
|
366 | sub extend($) { |
|
|
367 | my $img = $_[0]->clone; |
|
|
368 | $img->repeat_mode (urxvt::RepeatPad); |
|
|
369 | $img |
|
|
370 | } |
|
|
371 | |
|
|
372 | =back |
|
|
373 | |
265 | =head2 VARIABLES |
374 | =head2 VARIABLE VALUES |
266 | |
375 | |
267 | The following functions provide variable data such as the terminal |
376 | The following functions provide variable data such as the terminal window |
|
|
377 | dimensions. They are not (Perl-) variables, they just return stuff that |
268 | window dimensions. Most of them make your expression sensitive to some |
378 | varies. Most of them make your expression sensitive to some events, for |
269 | events, for example using C<TW> (terminal width) means your expression is |
379 | example using C<TW> (terminal width) means your expression is evaluated |
270 | evaluated again when the terminal is resized. |
380 | again when the terminal is resized. |
271 | |
381 | |
272 | =over 4 |
382 | =over 4 |
273 | |
383 | |
274 | =item TX |
384 | =item TX |
275 | |
385 | |
… | |
… | |
346 | $self->{counter} + 0 |
456 | $self->{counter} + 0 |
347 | } |
457 | } |
348 | |
458 | |
349 | =back |
459 | =back |
350 | |
460 | |
351 | =head2 TILING MODES |
461 | =head2 SHAPE CHANGING OPERATORS |
352 | |
462 | |
353 | The following operators modify the tiling mode of an image, that is, the |
463 | The following operators modify the shape, size or position of the image. |
354 | way that pixels outside the image area are painted when the image is used. |
|
|
355 | |
464 | |
356 | =over 4 |
465 | =over 4 |
357 | |
|
|
358 | =item tile $img |
|
|
359 | |
|
|
360 | Tiles the whole plane with the image and returns this new image - or in |
|
|
361 | other words, it returns a copy of the image in plane tiling mode. |
|
|
362 | |
|
|
363 | Example: load an image and tile it over the background, without |
|
|
364 | resizing. The C<tile> call is superfluous because C<load> already defaults |
|
|
365 | to tiling mode. |
|
|
366 | |
|
|
367 | tile load "mybg.png" |
|
|
368 | |
|
|
369 | =item mirror $img |
|
|
370 | |
|
|
371 | Similar to tile, but reflects the image each time it uses a new copy, so |
|
|
372 | that top edges always touch top edges, right edges always touch right |
|
|
373 | edges and so on (with normal tiling, left edges always touch right edges |
|
|
374 | and top always touch bottom edges). |
|
|
375 | |
|
|
376 | Example: load an image and mirror it over the background, avoiding sharp |
|
|
377 | edges at the image borders at the expense of mirroring the image itself |
|
|
378 | |
|
|
379 | mirror load "mybg.png" |
|
|
380 | |
|
|
381 | =item pad $img |
|
|
382 | |
|
|
383 | Takes an image and modifies it so that all pixels outside the image area |
|
|
384 | become transparent. This mode is most useful when you want to place an |
|
|
385 | image over another image or the background colour while leaving all |
|
|
386 | background pixels outside the image unchanged. |
|
|
387 | |
|
|
388 | Example: load an image and display it in the upper left corner. The rest |
|
|
389 | of the space is left "empty" (transparent or wahtever your compisotr does |
|
|
390 | in alpha mode, else background colour). |
|
|
391 | |
|
|
392 | pad load "mybg.png" |
|
|
393 | |
|
|
394 | =item extend $img |
|
|
395 | |
|
|
396 | Extends the image over the whole plane, using the closest pixel in the |
|
|
397 | area outside the image. This mode is mostly useful when you more complex |
|
|
398 | filtering operations and want the pixels outside the image to have the |
|
|
399 | same values as the pixels near the edge. |
|
|
400 | |
|
|
401 | Example: just for curiosity, how does this pixel extension stuff work? |
|
|
402 | |
|
|
403 | extend move 50, 50, load "mybg.png" |
|
|
404 | |
|
|
405 | =cut |
|
|
406 | |
|
|
407 | sub pad($) { |
|
|
408 | my $img = $_[0]->clone; |
|
|
409 | $img->repeat_mode (urxvt::RepeatNone); |
|
|
410 | $img |
|
|
411 | } |
|
|
412 | |
|
|
413 | sub tile($) { |
|
|
414 | my $img = $_[0]->clone; |
|
|
415 | $img->repeat_mode (urxvt::RepeatNormal); |
|
|
416 | $img |
|
|
417 | } |
|
|
418 | |
|
|
419 | sub mirror($) { |
|
|
420 | my $img = $_[0]->clone; |
|
|
421 | $img->repeat_mode (urxvt::RepeatReflect); |
|
|
422 | $img |
|
|
423 | } |
|
|
424 | |
|
|
425 | sub extend($) { |
|
|
426 | my $img = $_[0]->clone; |
|
|
427 | $img->repeat_mode (urxvt::RepeatPad); |
|
|
428 | $img |
|
|
429 | } |
|
|
430 | |
|
|
431 | =back |
|
|
432 | |
|
|
433 | =head2 PIXEL OPERATORS |
|
|
434 | |
|
|
435 | The following operators modify the image pixels in various ways. |
|
|
436 | |
|
|
437 | =over 4 |
|
|
438 | |
|
|
439 | =item clone $img |
|
|
440 | |
|
|
441 | Returns an exact copy of the image. |
|
|
442 | |
|
|
443 | =cut |
|
|
444 | |
|
|
445 | sub clone($) { |
|
|
446 | $_[0]->clone |
|
|
447 | } |
|
|
448 | |
466 | |
449 | =item clip $img |
467 | =item clip $img |
450 | |
468 | |
451 | =item clip $width, $height, $img |
469 | =item clip $width, $height, $img |
452 | |
470 | |
… | |
… | |
476 | $img->sub_rect ($_[0], $_[1], $w, $h) |
494 | $img->sub_rect ($_[0], $_[1], $w, $h) |
477 | } |
495 | } |
478 | |
496 | |
479 | =item scale $img |
497 | =item scale $img |
480 | |
498 | |
481 | =item scale $size_percent, $img |
499 | =item scale $size_factor, $img |
482 | |
500 | |
483 | =item scale $width_percent, $height_percent, $img |
501 | =item scale $width_factor, $height_factor, $img |
484 | |
502 | |
485 | Scales the image by the given percentages in horizontal |
503 | Scales the image by the given factors in horizontal |
486 | (C<$width_percent>) and vertical (C<$height_percent>) direction. |
504 | (C<$width>) and vertical (C<$height>) direction. |
487 | |
505 | |
488 | If only one percentage is give, it is used for both directions. |
506 | If only one factor is give, it is used for both directions. |
489 | |
507 | |
490 | If no percentages are given, scales the image to the window size without |
508 | If no factors are given, scales the image to the window size without |
491 | keeping aspect. |
509 | keeping aspect. |
492 | |
510 | |
493 | =item resize $width, $height, $img |
511 | =item resize $width, $height, $img |
494 | |
512 | |
495 | Resizes the image to exactly C<$width> times C<$height> pixels. |
513 | Resizes the image to exactly C<$width> times C<$height> pixels. |
496 | |
514 | |
497 | =cut |
515 | =item fit $img |
498 | |
516 | |
499 | #TODO: maximise, maximise_fill? |
517 | =item fit $width, $height, $img |
|
|
518 | |
|
|
519 | Fits the image into the given C<$width> and C<$height> without changing |
|
|
520 | aspect, or the terminal size. That means it will be shrunk or grown until |
|
|
521 | the whole image fits into the given area, possibly leaving borders. |
|
|
522 | |
|
|
523 | =item cover $img |
|
|
524 | |
|
|
525 | =item cover $width, $height, $img |
|
|
526 | |
|
|
527 | Similar to C<fit>, but shrinks or grows until all of the area is covered |
|
|
528 | by the image, so instead of potentially leaving borders, it will cut off |
|
|
529 | image data that doesn't fit. |
|
|
530 | |
|
|
531 | =cut |
500 | |
532 | |
501 | sub scale($;$;$) { |
533 | sub scale($;$;$) { |
502 | my $img = pop; |
534 | my $img = pop; |
503 | |
535 | |
504 | @_ == 2 ? $img->scale ($_[0] * $img->w * 0.01, $_[1] * $img->h * 0.01) |
536 | @_ == 2 ? $img->scale ($_[0] * $img->w, $_[1] * $img->h) |
505 | : @_ ? $img->scale ($_[0] * $img->w * 0.01, $_[0] * $img->h * 0.01) |
537 | : @_ ? $img->scale ($_[0] * $img->w, $_[0] * $img->h) |
506 | : $img->scale (TW, TH) |
538 | : $img->scale (TW, TH) |
507 | } |
539 | } |
508 | |
540 | |
509 | sub resize($$$) { |
541 | sub resize($$$) { |
510 | my $img = pop; |
542 | my $img = pop; |
511 | $img->scale ($_[0], $_[1]) |
543 | $img->scale ($_[0], $_[1]) |
|
|
544 | } |
|
|
545 | |
|
|
546 | sub fit($;$$) { |
|
|
547 | my $img = pop; |
|
|
548 | my $w = ($_[0] || TW) / $img->w; |
|
|
549 | my $h = ($_[1] || TH) / $img->h; |
|
|
550 | scale +(min $w, $h), $img |
|
|
551 | } |
|
|
552 | |
|
|
553 | sub cover($;$$) { |
|
|
554 | my $img = pop; |
|
|
555 | my $w = ($_[0] || TW) / $img->w; |
|
|
556 | my $h = ($_[1] || TH) / $img->h; |
|
|
557 | scale +(max $w, $h), $img |
512 | } |
558 | } |
513 | |
559 | |
514 | =item move $dx, $dy, $img |
560 | =item move $dx, $dy, $img |
515 | |
561 | |
516 | Moves the image by C<$dx> pixels in the horizontal, and C<$dy> pixels in |
562 | Moves the image by C<$dx> pixels in the horizontal, and C<$dy> pixels in |
517 | the vertical. |
563 | the vertical. |
518 | |
564 | |
519 | Example: move the image right by 20 pixels and down by 30. |
565 | Example: move the image right by 20 pixels and down by 30. |
520 | |
566 | |
521 | move 20, 30, ... |
567 | move 20, 30, ... |
|
|
568 | |
|
|
569 | =item align $xalign, $yalign, $img |
|
|
570 | |
|
|
571 | Aligns the image according to a factor - C<0> means the image is moved to |
|
|
572 | the left or top edge (for C<$xalign> or C<$yalign>), C<0.5> means it is |
|
|
573 | exactly centered and C<1> means it touches the right or bottom edge. |
|
|
574 | |
|
|
575 | Example: remove any visible border around an image, center it vertically but move |
|
|
576 | it to the right hand side. |
|
|
577 | |
|
|
578 | align 1, 0.5, pad $img |
|
|
579 | |
|
|
580 | =item center $img |
|
|
581 | |
|
|
582 | =item center $width, $height, $img |
|
|
583 | |
|
|
584 | Centers the image, i.e. the center of the image is moved to the center of |
|
|
585 | the terminal window (or the box specified by C<$width> and C<$height> if |
|
|
586 | given). |
|
|
587 | |
|
|
588 | Example: load an image and center it. |
|
|
589 | |
|
|
590 | center pad load "mybg.png" |
522 | |
591 | |
523 | =item rootalign $img |
592 | =item rootalign $img |
524 | |
593 | |
525 | Moves the image so that it appears glued to the screen as opposed to the |
594 | Moves the image so that it appears glued to the screen as opposed to the |
526 | window. This gives the illusion of a larger area behind the window. It is |
595 | window. This gives the illusion of a larger area behind the window. It is |
… | |
… | |
532 | rootalign mirror load "mybg.png" |
601 | rootalign mirror load "mybg.png" |
533 | |
602 | |
534 | Example: take the screen background and align it, giving the illusion of |
603 | Example: take the screen background and align it, giving the illusion of |
535 | transparency as long as the window isn't in front of other windows. |
604 | transparency as long as the window isn't in front of other windows. |
536 | |
605 | |
537 | rootalign root |
606 | rootalign root |
538 | |
607 | |
539 | =cut |
608 | =cut |
540 | |
609 | |
541 | sub move($$;$) { |
610 | sub move($$;$) { |
542 | my $img = pop->clone; |
611 | my $img = pop->clone; |
543 | $img->move ($_[0], $_[1]); |
612 | $img->move ($_[0], $_[1]); |
544 | $img |
613 | $img |
545 | } |
614 | } |
546 | |
615 | |
|
|
616 | sub align($;$$) { |
|
|
617 | my $img = pop; |
|
|
618 | |
|
|
619 | move $_[0] * (TW - $img->w), |
|
|
620 | $_[1] * (TH - $img->h), |
|
|
621 | $img |
|
|
622 | } |
|
|
623 | |
|
|
624 | sub center($;$$) { |
|
|
625 | my $img = pop; |
|
|
626 | my $w = $_[0] || TW; |
|
|
627 | my $h = $_[1] || TH; |
|
|
628 | |
|
|
629 | move 0.5 * ($w - $img->w), 0.5 * ($h - $img->h), $img |
|
|
630 | } |
|
|
631 | |
547 | sub rootalign($) { |
632 | sub rootalign($) { |
548 | move -TX, -TY, $_[0] |
633 | move -TX, -TY, $_[0] |
549 | } |
634 | } |
550 | |
635 | |
|
|
636 | =back |
|
|
637 | |
|
|
638 | =head2 COLOUR MODIFICATIONS |
|
|
639 | |
|
|
640 | The following operators change the pixels of the image. |
|
|
641 | |
|
|
642 | =over 4 |
|
|
643 | |
551 | =item contrast $factor, $img |
644 | =item contrast $factor, $img |
552 | |
645 | |
553 | =item contrast $r, $g, $b, $img |
646 | =item contrast $r, $g, $b, $img |
554 | |
647 | |
555 | =item contrast $r, $g, $b, $a, $img |
648 | =item contrast $r, $g, $b, $a, $img |
556 | |
649 | |
557 | Adjusts the I<contrast> of an image. |
650 | Adjusts the I<contrast> of an image. |
558 | |
651 | |
559 | #TODO# |
652 | The first form applies a single C<$factor> to red, green and blue, the |
|
|
653 | second form applies separate factors to each colour channel, and the last |
|
|
654 | form includes the alpha channel. |
560 | |
655 | |
|
|
656 | Values from 0 to 1 lower the contrast, values higher than 1 increase the |
|
|
657 | contrast. |
|
|
658 | |
|
|
659 | Due to limitations in the underlying XRender extension, lowering contrast |
|
|
660 | also reduces brightness, while increasing contrast currently also |
|
|
661 | increases brightness. |
|
|
662 | |
561 | =item brightness $factor, $img |
663 | =item brightness $bias, $img |
562 | |
664 | |
563 | =item brightness $r, $g, $b, $img |
665 | =item brightness $r, $g, $b, $img |
564 | |
666 | |
565 | =item brightness $r, $g, $b, $a, $img |
667 | =item brightness $r, $g, $b, $a, $img |
566 | |
668 | |
567 | Adjusts the brightness of an image. |
669 | Adjusts the brightness of an image. |
|
|
670 | |
|
|
671 | The first form applies a single C<$bias> to red, green and blue, the |
|
|
672 | second form applies separate biases to each colour channel, and the last |
|
|
673 | form includes the alpha channel. |
|
|
674 | |
|
|
675 | Values less than 0 reduce brightness, while values larger than 0 increase |
|
|
676 | it. Useful range is from -1 to 1 - the former results in a black, the |
|
|
677 | latter in a white picture. |
|
|
678 | |
|
|
679 | Due to idiosynchrasies in the underlying XRender extension, biases less |
|
|
680 | than zero can be I<very> slow. |
568 | |
681 | |
569 | =cut |
682 | =cut |
570 | |
683 | |
571 | sub contrast($$;$$;$) { |
684 | sub contrast($$;$$;$) { |
572 | my $img = pop; |
685 | my $img = pop; |
… | |
… | |
612 | } |
725 | } |
613 | |
726 | |
614 | =item rotate $new_width, $new_height, $center_x, $center_y, $degrees |
727 | =item rotate $new_width, $new_height, $center_x, $center_y, $degrees |
615 | |
728 | |
616 | Rotates the image by C<$degrees> degrees, counter-clockwise, around the |
729 | Rotates the image by C<$degrees> degrees, counter-clockwise, around the |
617 | pointer at C<$center_x> and C<$center_y> (specified as percentage of image |
730 | pointer at C<$center_x> and C<$center_y> (specified as factor of image |
618 | width/height), generating a new image with width C<$new_width> and height |
731 | width/height), generating a new image with width C<$new_width> and height |
619 | C<$new_height>. |
732 | C<$new_height>. |
620 | |
733 | |
621 | #TODO# new width, height, maybe more operators? |
734 | #TODO# new width, height, maybe more operators? |
622 | |
735 | |
… | |
… | |
627 | sub rotate($$$$$$) { |
740 | sub rotate($$$$$$) { |
628 | my $img = pop; |
741 | my $img = pop; |
629 | $img->rotate ( |
742 | $img->rotate ( |
630 | $_[0], |
743 | $_[0], |
631 | $_[1], |
744 | $_[1], |
632 | $_[2] * $img->w * .01, |
745 | $_[2] * $img->w, |
633 | $_[3] * $img->h * .01, |
746 | $_[3] * $img->h, |
634 | $_[4] * (3.14159265 / 180), |
747 | $_[4] * (3.14159265 / 180), |
635 | ) |
748 | ) |
636 | } |
749 | } |
637 | |
750 | |
638 | =back |
751 | =back |
… | |
… | |
749 | or return; |
862 | or return; |
750 | |
863 | |
751 | $self->set_expr (parse_expr $expr); |
864 | $self->set_expr (parse_expr $expr); |
752 | $self->{border} = $self->x_resource_boolean ("background.border"); |
865 | $self->{border} = $self->x_resource_boolean ("background.border"); |
753 | |
866 | |
|
|
867 | $MIN_INTERVAL = $self->x_resource ("background.interval"); |
|
|
868 | |
754 | () |
869 | () |
755 | } |
870 | } |
756 | |
871 | |