[ViewVC] Diff of: cvs/rxvt-unicode/src/perl/background

Comparing rxvt-unicode/src/perl/background (file contents):
Revision 1.41 by root, Fri Jun 8 22:21:48 2012 UTC vs.
Revision 1.58 by root, Thu Jun 14 18:13:19 2012 UTC

…		…
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		5	#:META:X_RESOURCE:%.interval:seconds:minimum time between updates
6	#TODO: once, rootalign
7		6
8	=head1 NAME	7	=head1 NAME
9		8
10	background - manage terminal background	9	background - manage terminal background
11		10
12	=head1 SYNOPSIS	11	=head1 SYNOPSIS
13		12
14	urxvt --background-expr 'background expression'	13	urxvt --background-expr 'background expression'
15	--background-border	14	--background-border
		15	--background-interval seconds
16		16
17	=head1 DESCRIPTION	17	=head1 DESCRIPTION
18		18
19	This extension manages the terminal background by creating a picture that	19	This extension manages the terminal background by creating a picture that
20	is behind the text, replacing the normal background colour.	20	is behind the text, replacing the normal background colour.
57		57
58	For example, an expression such as C<scale load "$HOME/mybg.png"> scales the	58	For example, an expression such as C<scale load "$HOME/mybg.png"> scales the
59	image to the window size, so it relies on the window size and will	59	image to the window size, so it relies on the window size and will
60	be reevaluated each time it is changed, but not when it moves for	60	be reevaluated each time it is changed, but not when it moves for
61	example. That ensures that the picture always fills the terminal, even	61	example. That ensures that the picture always fills the terminal, even
62	after it's size changes.	62	after its size changes.
63		63
64	=head2 EXPRESSIONS	64	=head2 EXPRESSIONS
65		65
66	Expressions are normal Perl expressions, in fact, they are Perl blocks -	66	Expressions are normal Perl expressions, in fact, they are Perl blocks -
67	which means you could use multiple lines and statements:	67	which means you could use multiple lines and statements:
…		…
71	return scale load "$HOME/weekday.png";	71	return scale load "$HOME/weekday.png";
72	} else {	72	} else {
73	return scale load "$HOME/sunday.png";	73	return scale load "$HOME/sunday.png";
74	}	74	}
75		75
76	This expression gets evaluated once per hour. It will set F<sunday.png> as	76	This expression is evaluated once per hour. It will set F<sunday.png> as
77	background on Sundays, and F<weekday.png> on all other days.	77	background on Sundays, and F<weekday.png> on all other days.
78		78
79	Fortunately, we expect that most expressions will be much simpler, with	79	Fortunately, we expect that most expressions will be much simpler, with
80	little Perl knowledge needed.	80	little Perl knowledge needed.
81		81
…		…
99	its result becomes the argument to the C<scale> function.	99	its result becomes the argument to the C<scale> function.
100		100
101	Many operators also allow some parameters preceding the input image	101	Many operators also allow some parameters preceding the input image
102	that modify its behaviour. For example, C<scale> without any additional	102	that modify its behaviour. For example, C<scale> without any additional
103	arguments scales the image to size of the terminal window. If you specify	103	arguments scales the image to size of the terminal window. If you specify
104	an additional argument, it uses it as a percentage:	104	an additional argument, it uses it as a scale factor (multiply by 100 to
		105	get a percentage):
105		106
106	scale 200, load "$HOME/mypic.png"	107	scale 2, load "$HOME/mypic.png"
107		108
108	This enlarges the image by a factor of 2 (200%). As you can see, C<scale>	109	This enlarges the image by a factor of 2 (200%). As you can see, C<scale>
109	has now two arguments, the C<200> and the C<load> expression, while	110	has now two arguments, the C<200> and the C<load> expression, while
110	C<load> only has one argument. Arguments are separated from each other by	111	C<load> only has one argument. Arguments are separated from each other by
111	commas.	112	commas.
112		113
113	Scale also accepts two arguments, which are then separate factors for both	114	Scale also accepts two arguments, which are then separate factors for both
114	horizontal and vertical dimensions. For example, this halves the image	115	horizontal and vertical dimensions. For example, this halves the image
115	width and doubles the image height:	116	width and doubles the image height:
116		117
117	scale 50, 200, load "$HOME/mypic.png"	118	scale 0.5, 2, load "$HOME/mypic.png"
118		119
119	Other effects than scalign are also readily available, for exmaple, you can	120	Other effects than scaling are also readily available, for example, you can
120	tile the image to fill the whole window, instead of resizing it:	121	tile the image to fill the whole window, instead of resizing it:
121		122
122	tile load "$HOME/mypic.png"	123	tile load "$HOME/mypic.png"
123		124
124	In fact, images returned by C<load> are in C<tile> mode by default, so the C<tile> operator	125	In fact, images returned by C<load> are in C<tile> mode by default, so the C<tile> operator
…		…
150	This only works for one cycle though, so as long as you load the same	151	This only works for one cycle though, so as long as you load the same
151	image every time, it will always be cached, but when you load a different	152	image every time, it will always be cached, but when you load a different
152	image, it will forget about the first one.	153	image, it will forget about the first one.
153		154
154	This allows you to either speed things up by keeping multiple images in	155	This allows you to either speed things up by keeping multiple images in
155	memory, or comserve memory by loading images more often.	156	memory, or conserve memory by loading images more often.
156		157
157	For example, you can keep two images in memory and use a random one like	158	For example, you can keep two images in memory and use a random one like
158	this:	159	this:
159		160
160	my $img1 = load "img1.png";	161	my $img1 = load "img1.png";
…		…
188	overwriting borders and any other areas, such as the scrollbar.	189	overwriting borders and any other areas, such as the scrollbar.
189		190
190	Specifying this flag changes the behaviour, so that the image only	191	Specifying this flag changes the behaviour, so that the image only
191	replaces the background of the character area.	192	replaces the background of the character area.
192		193
		194	=item --background-interval seconds
		195
		196	Since some operations in the underlying XRender extension can effectively
		197	freeze your X-server for prolonged time, this extension enforces a minimum
		198	time between updates, which is normally about 0.1 seconds.
		199
		200	If you want to do updates more often, you can decrease this safety
		201	interval with this switch.
		202
193	=back	203	=back
194		204
195	=cut	205	=cut
196		206
		207	our %_IMG_CACHE;
197	our $HOME;	208	our $HOME;
198	our ($self, $old, $new);	209	our ($self, $old, $new);
199	our ($x, $y, $w, $h);	210	our ($x, $y, $w, $h);
200		211
201	# enforce at least this interval between updates	212	# enforce at least this interval between updates
202	our $MIN_INTERVAL = 1/100;	213	our $MIN_INTERVAL = 6/59.951;
203		214
204	{	215	{
205	package urxvt::bgdsl; # background language	216	package urxvt::bgdsl; # background language
		217
		218	use List::Util qw(min max sum shuffle);
206		219
207	=head2 PROVIDERS/GENERATORS	220	=head2 PROVIDERS/GENERATORS
208		221
209	These functions provide an image, by loading it from disk, grabbing it	222	These functions provide an image, by loading it from disk, grabbing it
210	from the root screen or by simply generating it. They are used as starting	223	from the root screen or by simply generating it. They are used as starting
…		…
215	=item load $path	228	=item load $path
216		229
217	Loads the image at the given C<$path>. The image is set to plane tiling	230	Loads the image at the given C<$path>. The image is set to plane tiling
218	mode.	231	mode.
219		232
220	Loaded images will be cached for one cycle.	233	Loaded images will be cached for one cycle, and shared between temrinals
		234	running in the same process (e.g. in C<urxvtd>).
221		235
		236	=item load_uc $path
		237
		238	Load uncached - same as load, but does not cache the image. This function
		239	is most useufl if you want to optimise a background expression in some
		240	way.
		241
222	=cut	242	=cut
		243
		244	sub load_uc($) {
		245	my ($path) = @_;
		246
		247	$_IMG_CACHE{$path} \|\| do {
		248	my $img = $self->new_img_from_file ($path);
		249	Scalar::Util::weaken ($_IMG_CACHE{$path} = $img);
		250	$img
		251	}
		252	}
223		253
224	sub load($) {	254	sub load($) {
225	my ($path) = @_;	255	my ($path) = @_;
226		256
227	$new->{load}{$path} = $old->{load}{$path} \|\| $self->new_img_from_file ($path);	257	$new->{load}{$path} = $old->{load}{$path} \|\| load_uc $path;
228	}	258	}
229		259
230	=item root	260	=item root
231		261
232	Returns the root window pixmap, that is, hopefully, the background image	262	Returns the root window pixmap, that is, hopefully, the background image
…		…
236	reevaluated when the bg image changes.	266	reevaluated when the bg image changes.
237		267
238	=cut	268	=cut
239		269
240	sub root() {	270	sub root() {
241	$new->{rootpmap_sensitive} = 1;	271	$new->{again}{rootpmap} = 1;
242	die "root op not supported, exg, we need you";	272	$self->new_img_from_root
243	}	273	}
244		274
245	=item solid $colour	275	=item solid $colour
246		276
247	=item solid $width, $height, $colour	277	=item solid $width, $height, $colour
…		…
252	If C<$width> and C<$height> are omitted, it creates a 1x1 image, which is	282	If C<$width> and C<$height> are omitted, it creates a 1x1 image, which is
253	useful for solid backgrounds or for use in filtering effects.	283	useful for solid backgrounds or for use in filtering effects.
254		284
255	=cut	285	=cut
256		286
257	sub solid($$;$) {	287	sub solid($;$$) {
258	my $colour = pop;	288	my $colour = pop;
259		289
260	my $img = $self->new_img (urxvt::PictStandardARGB32, $_[0] \|\| 1, $_[1] \|\| 1);	290	my $img = $self->new_img (urxvt::PictStandardARGB32, $_[0] \|\| 1, $_[1] \|\| 1);
261	$img->fill ($colour);	291	$img->fill ($colour);
262	$img	292	$img
263	}	293	}
264		294
265	=back	295	=item clone $img
266		296
267	=head2 VARIABLES	297	Returns an exact copy of the image. This is useful if you want to have
		298	multiple copies of the same image to apply different effects to.
268		299
269	The following functions provide variable data such as the terminal window
270	dimensions. They are not (Perl-) variables, they jsut return stuff that
271	varies. Most of them make your expression sensitive to some events, for
272	example using C<TW> (terminal width) means your expression is evaluated
273	again when the terminal is resized.
274
275	=over 4
276
277	=item TX
278
279	=item TY
280
281	Return the X and Y coordinates of the terminal window (the terminal
282	window is the full window by default, and the character area only when in
283	border-respect mode).
284
285	Using these functions make your expression sensitive to window moves.
286
287	These functions are mainly useful to align images to the root window.
288
289	Example: load an image and align it so it looks as if anchored to the
290	background.
291
292	move -TX, -TY, load "mybg.png"
293
294	=item TW
295
296	Return the width (C<TW>) and height (C<TH>) of the terminal window (the
297	terminal window is the full window by default, and the character area only
298	when in border-respect mode).
299
300	Using these functions make your expression sensitive to window resizes.
301
302	These functions are mainly useful to scale images, or to clip images to
303	the window size to conserve memory.
304
305	Example: take the screen background, clip it to the window size, blur it a
306	bit, align it to the window position and use it as background.
307
308	clip move -TX, -TY, blur 5, root
309
310	=cut	300	=cut
311		301
312	sub TX() { $new->{position_sensitive} = 1; $x }
313	sub TY() { $new->{position_sensitive} = 1; $y }
314	sub TW() { $new->{size_sensitive} = 1; $w }
315	sub TH() { $new->{size_sensitive} = 1; $h }
316
317	=item now
318
319	Returns the current time as (fractional) seconds since the epoch.
320
321	Using this expression does I<not> make your expression sensitive to time,
322	but the next two functions do.
323
324	=item again $seconds
325
326	When this function is used the expression will be reevaluated again in
327	C<$seconds> seconds.
328
329	Example: load some image and rotate it according to the time of day (as if it were
330	the hour pointer of a clock). Update this image every minute.
331
332	again 60; rotate TW, TH, 50, 50, (now % 86400) * -720 / 86400, scale load "myclock.png"
333
334	=item counter $seconds
335
336	Like C<again>, but also returns an increasing counter value, starting at
337	0, which might be useful for some simple animation effects.
338
339	=cut
340
341	sub now() { urxvt::NOW }
342
343	sub again($) {
344	$new->{again} = $_[0];
345	}
346
347	sub counter($) {	302	sub clone($) {
348	$new->{again} = $_[0];	303	$_[0]->clone
349	$self->{counter} + 0
350	}	304	}
351		305
352	=back	306	=item merge $img ...
		307
		308	Takes any number of images and merges them together, creating a single
		309	image containing them all.
		310
		311	=cut
		312
		313	sub merge(@) {
		314	# rather annoyingly clumsy, but optimisation is for another time
		315
		316	my $x0 = 1e9;
		317	my $y0 = 1e9;
		318	my $x1 = -1e9;
		319	my $y1 = -1e9;
		320
		321	for (@_) {
		322	my ($x, $y, $w, $h) = $_->geometry;
		323
		324	$x0 = $x if $x0 > $x;
		325	$y0 = $y if $y0 > $y;
		326
		327	$x += $w;
		328	$y += $h;
		329
		330	$x1 = $x if $x1 > $x;
		331	$y1 = $y if $y1 > $y;
		332	}
		333
		334	my $base = $self->new_img ($x0, $y0, $x1 - $x0, $y1 - $y0);
		335	$base->fill ([0, 0, 0, 0]);
		336
		337	$base->blend (1., $_)
		338	for @_;
		339
		340	$base
		341	}
353		342
354	=head2 TILING MODES	343	=head2 TILING MODES
355		344
356	The following operators modify the tiling mode of an image, that is, the	345	The following operators modify the tiling mode of an image, that is, the
357	way that pixels outside the image area are painted when the image is used.	346	way that pixels outside the image area are painted when the image is used.
…		…
387	become transparent. This mode is most useful when you want to place an	376	become transparent. This mode is most useful when you want to place an
388	image over another image or the background colour while leaving all	377	image over another image or the background colour while leaving all
389	background pixels outside the image unchanged.	378	background pixels outside the image unchanged.
390		379
391	Example: load an image and display it in the upper left corner. The rest	380	Example: load an image and display it in the upper left corner. The rest
392	of the space is left "empty" (transparent or wahtever your compisotr does	381	of the space is left "empty" (transparent or whatever your compositor does
393	in alpha mode, else background colour).	382	in alpha mode, else background colour).
394		383
395	pad load "mybg.png"	384	pad load "mybg.png"
396		385
397	=item extend $img	386	=item extend $img
398		387
399	Extends the image over the whole plane, using the closest pixel in the	388	Extends the image over the whole plane, using the closest pixel in the
400	area outside the image. This mode is mostly useful when you more complex	389	area outside the image. This mode is mostly useful when you use more complex
401	filtering operations and want the pixels outside the image to have the	390	filtering operations and want the pixels outside the image to have the
402	same values as the pixels near the edge.	391	same values as the pixels near the edge.
403		392
404	Example: just for curiosity, how does this pixel extension stuff work?	393	Example: just for curiosity, how does this pixel extension stuff work?
405		394
…		…
431	$img	420	$img
432	}	421	}
433		422
434	=back	423	=back
435		424
436	=head2 PIXEL OPERATORS	425	=head2 VARIABLE VALUES
437		426
438	The following operators modify the image pixels in various ways.	427	The following functions provide variable data such as the terminal window
		428	dimensions. They are not (Perl-) variables, they just return stuff that
		429	varies. Most of them make your expression sensitive to some events, for
		430	example using C<TW> (terminal width) means your expression is evaluated
		431	again when the terminal is resized.
439		432
440	=over 4	433	=over 4
441		434
442	=item clone $img	435	=item TX
443		436
444	Returns an exact copy of the image.	437	=item TY
445		438
446	=cut	439	Return the X and Y coordinates of the terminal window (the terminal
		440	window is the full window by default, and the character area only when in
		441	border-respect mode).
447		442
		443	Using these functions make your expression sensitive to window moves.
		444
		445	These functions are mainly useful to align images to the root window.
		446
		447	Example: load an image and align it so it looks as if anchored to the
		448	background.
		449
		450	move -TX, -TY, load "mybg.png"
		451
		452	=item TW
		453
		454	Return the width (C<TW>) and height (C<TH>) of the terminal window (the
		455	terminal window is the full window by default, and the character area only
		456	when in border-respect mode).
		457
		458	Using these functions make your expression sensitive to window resizes.
		459
		460	These functions are mainly useful to scale images, or to clip images to
		461	the window size to conserve memory.
		462
		463	Example: take the screen background, clip it to the window size, blur it a
		464	bit, align it to the window position and use it as background.
		465
		466	clip move -TX, -TY, once { blur 5, root }
		467
		468	=cut
		469
		470	sub TX() { $new->{again}{position} = 1; $x }
		471	sub TY() { $new->{again}{position} = 1; $y }
		472	sub TW() { $new->{again}{size} = 1; $w }
		473	sub TH() { $new->{again}{size} = 1; $h }
		474
		475	=item now
		476
		477	Returns the current time as (fractional) seconds since the epoch.
		478
		479	Using this expression does I<not> make your expression sensitive to time,
		480	but the next two functions do.
		481
		482	=item again $seconds
		483
		484	When this function is used the expression will be reevaluated again in
		485	C<$seconds> seconds.
		486
		487	Example: load some image and rotate it according to the time of day (as if it were
		488	the hour pointer of a clock). Update this image every minute.
		489
		490	again 60; rotate 50, 50, (now % 86400) * -720 / 86400, scale load "myclock.png"
		491
		492	=item counter $seconds
		493
		494	Like C<again>, but also returns an increasing counter value, starting at
		495	0, which might be useful for some simple animation effects.
		496
		497	=cut
		498
		499	sub now() { urxvt::NOW }
		500
		501	sub again($) {
		502	$new->{again}{time} = $_[0];
		503	}
		504
448	sub clone($) {	505	sub counter($) {
449	$_[0]->clone	506	$new->{again}{time} = $_[0];
		507	$self->{counter} + 0
450	}	508	}
		509
		510	=back
		511
		512	=head2 SHAPE CHANGING OPERATORS
		513
		514	The following operators modify the shape, size or position of the image.
		515
		516	=over 4
451		517
452	=item clip $img	518	=item clip $img
453		519
454	=item clip $width, $height, $img	520	=item clip $width, $height, $img
455		521
…		…
479	$img->sub_rect ($_[0], $_[1], $w, $h)	545	$img->sub_rect ($_[0], $_[1], $w, $h)
480	}	546	}
481		547
482	=item scale $img	548	=item scale $img
483		549
484	=item scale $size_percent, $img	550	=item scale $size_factor, $img
485		551
486	=item scale $width_percent, $height_percent, $img	552	=item scale $width_factor, $height_factor, $img
487		553
488	Scales the image by the given percentages in horizontal	554	Scales the image by the given factors in horizontal
489	(C<$width_percent>) and vertical (C<$height_percent>) direction.	555	(C<$width>) and vertical (C<$height>) direction.
490		556
491	If only one percentage is give, it is used for both directions.	557	If only one factor is give, it is used for both directions.
492		558
493	If no percentages are given, scales the image to the window size without	559	If no factors are given, scales the image to the window size without
494	keeping aspect.	560	keeping aspect.
495		561
496	=item resize $width, $height, $img	562	=item resize $width, $height, $img
497		563
498	Resizes the image to exactly C<$width> times C<$height> pixels.	564	Resizes the image to exactly C<$width> times C<$height> pixels.
499		565
500	=cut	566	=item fit $img
501		567
502	#TODO: maximise, maximise_fill?	568	=item fit $width, $height, $img
		569
		570	Fits the image into the given C<$width> and C<$height> without changing
		571	aspect, or the terminal size. That means it will be shrunk or grown until
		572	the whole image fits into the given area, possibly leaving borders.
		573
		574	=item cover $img
		575
		576	=item cover $width, $height, $img
		577
		578	Similar to C<fit>, but shrinks or grows until all of the area is covered
		579	by the image, so instead of potentially leaving borders, it will cut off
		580	image data that doesn't fit.
		581
		582	=cut
503		583
504	sub scale($;$;$) {	584	sub scale($;$;$) {
505	my $img = pop;	585	my $img = pop;
506		586
507	@_ == 2 ? $img->scale ($_[0] * $img->w * 0.01, $_[1] * $img->h * 0.01)	587	@_ == 2 ? $img->scale ($_[0] * $img->w, $_[1] * $img->h)
508	: @_ ? $img->scale ($_[0] * $img->w * 0.01, $_[0] * $img->h * 0.01)	588	: @_ ? $img->scale ($_[0] * $img->w, $_[0] * $img->h)
509	: $img->scale (TW, TH)	589	: $img->scale (TW, TH)
510	}	590	}
511		591
512	sub resize($$$) {	592	sub resize($$$) {
513	my $img = pop;	593	my $img = pop;
514	$img->scale ($_[0], $_[1])	594	$img->scale ($_[0], $_[1])
		595	}
		596
		597	sub fit($;$$) {
		598	my $img = pop;
		599	my $w = ($_[0] \|\| TW) / $img->w;
		600	my $h = ($_[1] \|\| TH) / $img->h;
		601	scale +(min $w, $h), $img
		602	}
		603
		604	sub cover($;$$) {
		605	my $img = pop;
		606	my $w = ($_[0] \|\| TW) / $img->w;
		607	my $h = ($_[1] \|\| TH) / $img->h;
		608	scale +(max $w, $h), $img
515	}	609	}
516		610
517	=item move $dx, $dy, $img	611	=item move $dx, $dy, $img
518		612
519	Moves the image by C<$dx> pixels in the horizontal, and C<$dy> pixels in	613	Moves the image by C<$dx> pixels in the horizontal, and C<$dy> pixels in
520	the vertical.	614	the vertical.
521		615
522	Example: move the image right by 20 pixels and down by 30.	616	Example: move the image right by 20 pixels and down by 30.
523		617
524	move 20, 30, ...	618	move 20, 30, ...
		619
		620	=item align $xalign, $yalign, $img
		621
		622	Aligns the image according to a factor - C<0> means the image is moved to
		623	the left or top edge (for C<$xalign> or C<$yalign>), C<0.5> means it is
		624	exactly centered and C<1> means it touches the right or bottom edge.
		625
		626	Example: remove any visible border around an image, center it vertically but move
		627	it to the right hand side.
		628
		629	align 1, 0.5, pad $img
		630
		631	=item center $img
		632
		633	=item center $width, $height, $img
		634
		635	Centers the image, i.e. the center of the image is moved to the center of
		636	the terminal window (or the box specified by C<$width> and C<$height> if
		637	given).
		638
		639	Example: load an image and center it.
		640
		641	center pad load "mybg.png"
525		642
526	=item rootalign $img	643	=item rootalign $img
527		644
528	Moves the image so that it appears glued to the screen as opposed to the	645	Moves the image so that it appears glued to the screen as opposed to the
529	window. This gives the illusion of a larger area behind the window. It is	646	window. This gives the illusion of a larger area behind the window. It is
…		…
535	rootalign mirror load "mybg.png"	652	rootalign mirror load "mybg.png"
536		653
537	Example: take the screen background and align it, giving the illusion of	654	Example: take the screen background and align it, giving the illusion of
538	transparency as long as the window isn't in front of other windows.	655	transparency as long as the window isn't in front of other windows.
539		656
540	rootalign root	657	rootalign root
541		658
542	=cut	659	=cut
543		660
544	sub move($$;$) {	661	sub move($$;$) {
545	my $img = pop->clone;	662	my $img = pop->clone;
546	$img->move ($_[0], $_[1]);	663	$img->move ($_[0], $_[1]);
547	$img	664	$img
548	}	665	}
549		666
		667	sub align($;$$) {
		668	my $img = pop;
		669
		670	move $_[0] * (TW - $img->w),
		671	$_[1] * (TH - $img->h),
		672	$img
		673	}
		674
		675	sub center($;$$) {
		676	my $img = pop;
		677	my $w = $_[0] \|\| TW;
		678	my $h = $_[1] \|\| TH;
		679
		680	move 0.5 * ($w - $img->w), 0.5 * ($h - $img->h), $img
		681	}
		682
550	sub rootalign($) {	683	sub rootalign($) {
551	move -TX, -TY, $_[0]	684	move -TX, -TY, $_[0]
552	}	685	}
553		686
		687	=item rotate $center_x, $center_y, $degrees
		688
		689	Rotates the image by C<$degrees> degrees, counter-clockwise, around the
		690	pointer at C<$center_x> and C<$center_y> (specified as factor of image
		691	width/height).
		692
		693	#TODO# new width, height, maybe more operators?
		694
		695	Example: rotate the image by 90 degrees
		696
		697	=cut
		698
		699	sub rotate($$$$) {
		700	my $img = pop;
		701	$img->rotate (
		702	$_[0] * $img->w,
		703	$_[1] * $img->h,
		704	$_[2] * (3.14159265 / 180),
		705	)
		706	}
		707
		708	=back
		709
		710	=head2 COLOUR MODIFICATIONS
		711
		712	The following operators change the pixels of the image.
		713
		714	=over 4
		715
554	=item contrast $factor, $img	716	=item contrast $factor, $img
555		717
556	=item contrast $r, $g, $b, $img	718	=item contrast $r, $g, $b, $img
557		719
558	=item contrast $r, $g, $b, $a, $img	720	=item contrast $r, $g, $b, $a, $img
559		721
560	Adjusts the I<contrast> of an image.	722	Adjusts the I<contrast> of an image.
561		723
562	#TODO#	724	The first form applies a single C<$factor> to red, green and blue, the
		725	second form applies separate factors to each colour channel, and the last
		726	form includes the alpha channel.
563		727
		728	Values from 0 to 1 lower the contrast, values higher than 1 increase the
		729	contrast.
		730
		731	Due to limitations in the underlying XRender extension, lowering contrast
		732	also reduces brightness, while increasing contrast currently also
		733	increases brightness.
		734
564	=item brightness $factor, $img	735	=item brightness $bias, $img
565		736
566	=item brightness $r, $g, $b, $img	737	=item brightness $r, $g, $b, $img
567		738
568	=item brightness $r, $g, $b, $a, $img	739	=item brightness $r, $g, $b, $a, $img
569		740
570	Adjusts the brightness of an image.	741	Adjusts the brightness of an image.
571		742
		743	The first form applies a single C<$bias> to red, green and blue, the
		744	second form applies separate biases to each colour channel, and the last
		745	form includes the alpha channel.
		746
		747	Values less than 0 reduce brightness, while values larger than 0 increase
		748	it. Useful range is from -1 to 1 - the former results in a black, the
		749	latter in a white picture.
		750
		751	Due to idiosyncrasies in the underlying XRender extension, biases less
		752	than zero can be I<very> slow.
		753
572	=cut	754	=cut
573		755
574	sub contrast($$;$$;$) {	756	sub contrast($$;$$;$) {
575	my $img = pop;	757	my $img = pop;
576	my ($r, $g, $b, $a) = @_;	758	my ($r, $g, $b, $a) = @_;
577		759
578	($g, $b) = ($r, $r) if @_ < 4;	760	($g, $b) = ($r, $r) if @_ < 3;
579	$a = 1 if @_ < 5;	761	$a = 1 if @_ < 4;
580		762
581	$img = $img->clone;	763	$img = $img->clone;
582	$img->contrast ($r, $g, $b, $a);	764	$img->contrast ($r, $g, $b, $a);
583	$img	765	$img
584	}	766	}
585		767
586	sub brightness($$;$$;$) {	768	sub brightness($$;$$;$) {
587	my $img = pop;	769	my $img = pop;
588	my ($r, $g, $b, $a) = @_;	770	my ($r, $g, $b, $a) = @_;
589		771
590	($g, $b) = ($r, $r) if @_ < 4;	772	($g, $b) = ($r, $r) if @_ < 3;
591	$a = 1 if @_ < 5;	773	$a = 1 if @_ < 4;
592		774
593	$img = $img->clone;	775	$img = $img->clone;
594	$img->brightness ($r, $g, $b, $a);	776	$img->brightness ($r, $g, $b, $a);
595	$img	777	$img
596	}	778	}
…		…
612	sub blur($$;$) {	794	sub blur($$;$) {
613	my $img = pop;	795	my $img = pop;
614	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])	796	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])
615	}	797	}
616		798
617	=item rotate $new_width, $new_height, $center_x, $center_y, $degrees	799	=back
618		800
619	Rotates the image by C<$degrees> degrees, counter-clockwise, around the	801	=head2 OTHER STUFF
620	pointer at C<$center_x> and C<$center_y> (specified as percentage of image
621	width/height), generating a new image with width C<$new_width> and height
622	C<$new_height>.
623		802
624	#TODO# new width, height, maybe more operators?	803	Anything that didn't fit any of the other categories, even after applying
		804	force and closing our eyes.
625		805
626	Example: rotate the image by 90 degrees	806	=over 4
627		807
628	=cut	808	=item once { ... }
629		809
630	sub rotate($$$$$$) {	810	This function takes a code block as argument, that is, one or more
631	my $img = pop;	811	statements enclosed by braces.
632	$img->rotate (	812
633	$_[0],	813	The trick is that this code block is only evaluated once - future calls
634	$_[1],	814	will simply return the original image (yes, it should only be used with
635	$_[2] * $img->w * .01,	815	images).
636	$_[3] * $img->h * .01,	816
637	$_[4] * (3.14159265 / 180),	817	This can be extremely useful to avoid redoign the same slow operations
		818	again and again- for example, if your background expression takes the root
		819	background, blurs it and then root-aligns it it would have to blur the
		820	root background on every window move or resize.
		821
		822	Putting the blur into a C<once> block will make sure the blur is only done
		823	once:
		824
		825	rootlign once { blur 10, root }
		826
		827	This leaves the question of how to force reevaluation of the block, in
		828	case the root background changes: Right now, all once blocks forget that
		829	they ahve been executed before each time the root background changes (if
		830	the expression is sensitive to that) or when C<once_again> is called.
		831
		832	=item once_again
		833
		834	Resets all C<once> block as if they had never been called, i.e. on the
		835	next call they will be reevaluated again.
		836
		837	=cut
		838
		839	sub once(&) {
		840	my $once = $self->{once_cache}{$_[0]+0} \|\|= do {
		841	local $new->{again};
		842	my @res = $_[0]();
		843	[$new->{again}, \@res]
638	)	844	};
		845
		846	$new->{again} = {
		847	%{ $new->{again} },
		848	%{ $once->[0] }
		849	};
		850
		851	# in scalar context we always return the first original result, which
		852	# is not quite how perl works.
		853	wantarray
		854	? @{ $once->[1] }
		855	: $once->[1][0]
		856	}
		857
		858	sub once_again() {
		859	delete $self->{once_cache};
639	}	860	}
640		861
641	=back	862	=back
642		863
643	=cut	864	=cut
…		…
686		907
687	# evaluate user expression	908	# evaluate user expression
688		909
689	my $img = eval { $self->{expr}->() };	910	my $img = eval { $self->{expr}->() };
690	warn $@ if $@;#d#	911	warn $@ if $@;#d#
691	die if !UNIVERSAL::isa $img, "urxvt::img";	912	die "background-expr did not return an image.\n" if !UNIVERSAL::isa $img, "urxvt::img";
692		913
693	$state->{size_sensitive} = 1	914	# if the expression is sensitive to external events, prepare reevaluation then
		915
		916	my $again = delete $state->{again};
		917
		918	$again->{size} = 1
694	if $img->repeat_mode != urxvt::RepeatNormal;	919	if $img->repeat_mode != urxvt::RepeatNormal;
695		920
696	# if the expression is sensitive to external events, prepare reevaluation then
697
698	my $repeat;
699
700	if (my $again = $state->{again}) {	921	if (my $again = $again->{time}) {
701	$repeat = 1;
702	my $self = $self;	922	my $self = $self;
703	$state->{timer} = $again == $old->{again}	923	$state->{timer} = $again == $old->{again}
704	? $old->{timer}	924	? $old->{timer}
705	: urxvt::timer->new->after ($again)->interval ($again)->cb (sub {	925	: urxvt::timer->new->after ($again)->interval ($again)->cb (sub {
706	++$self->{counter};	926	++$self->{counter};
707	$self->recalculate	927	$self->recalculate
708	});	928	});
709	}	929	}
710		930
711	if (delete $state->{position_sensitive}) {	931	if ($again->{position}) {
712	$repeat = 1;
713	$self->enable (position_change => sub { $_[0]->recalculate });	932	$self->enable (position_change => sub { $_[0]->recalculate });
714	} else {	933	} else {
715	$self->disable ("position_change");	934	$self->disable ("position_change");
716	}	935	}
717		936
718	if (delete $state->{size_sensitive}) {	937	if ($again->{size}) {
719	$repeat = 1;
720	$self->enable (size_change => sub { $_[0]->recalculate });	938	$self->enable (size_change => sub { $_[0]->recalculate });
721	} else {	939	} else {
722	$self->disable ("size_change");	940	$self->disable ("size_change");
723	}	941	}
724		942
725	if (delete $state->{rootpmap_sensitive}) {	943	if ($again->{rootpmap}) {
726	$repeat = 1;
727	$self->enable (rootpmap_change => sub { $_[0]->recalculate });	944	$self->enable (rootpmap_change => sub {
		945	delete $_[0]{once_cache}; # this will override once-block values from
		946	$_[0]->recalculate;
		947	});
728	} else {	948	} else {
729	$self->disable ("rootpmap_change");	949	$self->disable ("rootpmap_change");
730	}	950	}
731		951
732	# clear stuff we no longer need	952	# clear stuff we no longer need
733		953
734	%$old = ();	954	%$old = ();
735		955
736	unless ($repeat) {	956	unless (%$again) {
737	delete $self->{state};	957	delete $self->{state};
738	delete $self->{expr};	958	delete $self->{expr};
739	}	959	}
740		960
741	# set background pixmap	961	# set background pixmap
…		…
746	}	966	}
747		967
748	sub on_start {	968	sub on_start {
749	my ($self) = @_;	969	my ($self) = @_;
750		970
751	my $expr = $self->x_resource ("background.expr")	971	my $expr = $self->x_resource ("%.expr")
752	or return;	972	or return;
753		973
		974	$self->has_render
		975	or die "background extension needs RENDER extension 0.10 or higher, ignoring background-expr.\n";
		976
754	$self->set_expr (parse_expr $expr);	977	$self->set_expr (parse_expr $expr);
755	$self->{border} = $self->x_resource_boolean ("background.border");	978	$self->{border} = $self->x_resource_boolean ("%.border");
		979
		980	$MIN_INTERVAL = $self->x_resource ("%.interval");
756		981
757	()	982	()
758	}	983	}
759		984

Diff Legend

-–
+Removed lines
-+
+Added lines
-<
+Changed lines
->
+Changed lines

Comparing rxvt-unicode/src/perl/background (file contents): Revision 1.41 by root, Fri Jun 8 22:21:48 2012 UTC vs. Revision 1.58 by root, Thu Jun 14 18:13:19 2012 UTC

Diff Legend

Comparing rxvt-unicode/src/perl/background (file contents):
Revision 1.41 by root, Fri Jun 8 22:21:48 2012 UTC vs.
Revision 1.58 by root, Thu Jun 14 18:13:19 2012 UTC