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

Comparing rxvt-unicode/src/perl/background (file contents):
Revision 1.42 by root, Sun Jun 10 10:42:19 2012 UTC vs.
Revision 1.86 by sf-exg, Fri Oct 4 17:09:57 2013 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
		17	=head1 QUICK AND DIRTY CHEAT SHEET
		18
		19	Just load a random jpeg image and tile the background with it without
		20	scaling or anything else:
		21
		22	load "/path/to/img.jpg"
		23
		24	The same, but use mirroring/reflection instead of tiling:
		25
		26	mirror load "/path/to/img.jpg"
		27
		28	Load an image and scale it to exactly fill the terminal window:
		29
		30	scale keep { load "/path/to/img.jpg" }
		31
		32	Implement pseudo-transparency by using a suitably-aligned root pixmap
		33	as window background:
		34
		35	rootalign root
		36
		37	Likewise, but keep a blurred copy:
		38
		39	rootalign keep { blur 10, root }
16		40
17	=head1 DESCRIPTION	41	=head1 DESCRIPTION
18		42
19	This extension manages the terminal background by creating a picture that	43	This extension manages the terminal background by creating a picture that
20	is behind the text, replacing the normal background colour.	44	is behind the text, replacing the normal background colour.
26	to be as simple as possible.	50	to be as simple as possible.
27		51
28	For example, to load an image and scale it to the window size, you would	52	For example, to load an image and scale it to the window size, you would
29	use:	53	use:
30		54
31	urxvt --background-expr 'scale load "/path/to/mybg.png"'	55	urxvt --background-expr 'scale keep { load "/path/to/mybg.png" }'
32		56
33	Or specified as a X resource:	57	Or specified as a X resource:
34		58
35	URxvt.background-expr: scale load "/path/to/mybg.png"	59	URxvt.background-expr: scale keep { load "/path/to/mybg.png" }
36		60
37	=head1 THEORY OF OPERATION	61	=head1 THEORY OF OPERATION
38		62
39	At startup, just before the window is mapped for the first time, the	63	At startup, just before the window is mapped for the first time, the
40	expression is evaluated and must yield an image. The image is then	64	expression is evaluated and must yield an image. The image is then
…		…
53	If any of the parameters that the expression relies on changes (when the	77	If any of the parameters that the expression relies on changes (when the
54	window is moved or resized, its position or size changes; when the root	78	window is moved or resized, its position or size changes; when the root
55	pixmap is replaced by another one the root background changes; or when the	79	pixmap is replaced by another one the root background changes; or when the
56	timer elapses), then the expression will be evaluated again.	80	timer elapses), then the expression will be evaluated again.
57		81
58	For example, an expression such as C<scale load "$HOME/mybg.png"> scales the	82	For example, an expression such as C<scale keep { load "$HOME/mybg.png"
59	image to the window size, so it relies on the window size and will	83	}> scales the image to the window size, so it relies on the window size
60	be reevaluated each time it is changed, but not when it moves for	84	and will 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	85	example. That ensures that the picture always fills the terminal, even
62	after it's size changes.	86	after its size changes.
63		87
64	=head2 EXPRESSIONS	88	=head2 EXPRESSIONS
65		89
66	Expressions are normal Perl expressions, in fact, they are Perl blocks -	90	Expressions are normal Perl expressions, in fact, they are Perl blocks -
67	which means you could use multiple lines and statements:	91	which means you could use multiple lines and statements:
68		92
		93	scale keep {
69	again 3600;	94	again 3600;
70	if (localtime now)[6]) {	95	if (localtime now)[6]) {
71	return scale load "$HOME/weekday.png";	96	return load "$HOME/weekday.png";
72	} else {	97	} else {
73	return scale load "$HOME/sunday.png";	98	return load "$HOME/sunday.png";
		99	}
74	}	100	}
75		101
76	This expression gets evaluated once per hour. It will set F<sunday.png> as	102	This inner expression is evaluated once per hour (and whenever the
		103	terminal window is resized). It sets F<sunday.png> as background on
77	background on Sundays, and F<weekday.png> on all other days.	104	Sundays, and F<weekday.png> on all other days.
78		105
79	Fortunately, we expect that most expressions will be much simpler, with	106	Fortunately, we expect that most expressions will be much simpler, with
80	little Perl knowledge needed.	107	little Perl knowledge needed.
81		108
82	Basically, you always start with a function that "generates" an image	109	Basically, you always start with a function that "generates" an image
…		…
99	its result becomes the argument to the C<scale> function.	126	its result becomes the argument to the C<scale> function.
100		127
101	Many operators also allow some parameters preceding the input image	128	Many operators also allow some parameters preceding the input image
102	that modify its behaviour. For example, C<scale> without any additional	129	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	130	arguments scales the image to size of the terminal window. If you specify
104	an additional argument, it uses it as a percentage:	131	an additional argument, it uses it as a scale factor (multiply by 100 to
		132	get a percentage):
105		133
106	scale 200, load "$HOME/mypic.png"	134	scale 2, load "$HOME/mypic.png"
107		135
108	This enlarges the image by a factor of 2 (200%). As you can see, C<scale>	136	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	137	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	138	C<load> only has one argument. Arguments are separated from each other by
111	commas.	139	commas.
112		140
113	Scale also accepts two arguments, which are then separate factors for both	141	Scale also accepts two arguments, which are then separate factors for both
114	horizontal and vertical dimensions. For example, this halves the image	142	horizontal and vertical dimensions. For example, this halves the image
115	width and doubles the image height:	143	width and doubles the image height:
116		144
117	scale 50, 200, load "$HOME/mypic.png"	145	scale 0.5, 2, load "$HOME/mypic.png"
118		146
119	Other effects than scalign are also readily available, for exmaple, you can	147	IF you try out these expressions, you might suffer from some sluggishness,
120	tile the image to fill the whole window, instead of resizing it:	148	because each time the terminal is resized, it loads the PNG image again
		149	and scales it. Scaling is usually fast (and unavoidable), but loading the
		150	image can be quite time consuming. This is where C<keep> comes in handy:
121		151
		152	scale 0.5, 2, keep { load "$HOME/mypic.png" }
		153
		154	The C<keep> operator executes all the statements inside the braces only
		155	once, or when it thinks the outcome might change. In other cases it
		156	returns the last value computed by the brace block.
		157
		158	This means that the C<load> is only executed once, which makes it much
		159	faster, but also means that more memory is being used, because the loaded
		160	image must be kept in memory at all times. In this expression, the
		161	trade-off is likely worth it.
		162
		163	But back to effects: Other effects than scaling are also readily
		164	available, for example, you can tile the image to fill the whole window,
		165	instead of resizing it:
		166
122	tile load "$HOME/mypic.png"	167	tile keep { load "$HOME/mypic.png" }
123		168
124	In fact, images returned by C<load> are in C<tile> mode by default, so the C<tile> operator	169	In fact, images returned by C<load> are in C<tile> mode by default, so the
125	is kind of superfluous.	170	C<tile> operator is kind of superfluous.
126		171
127	Another common effect is to mirror the image, so that the same edges touch:	172	Another common effect is to mirror the image, so that the same edges
		173	touch:
128		174
129	mirror load "$HOME/mypic.png"	175	mirror keep { load "$HOME/mypic.png" }
130		176
131	This is also a typical background expression:	177	Another common background expression is:
132		178
133	rootalign root	179	rootalign root
134		180
135	It first takes a snapshot of the screen background image, and then	181	This one first takes a snapshot of the screen background image, and then
136	moves it to the upper left corner of the screen - the result is	182	moves it to the upper left corner of the screen (as opposed to the upper
137	pseudo-transparency, as the image seems to be static while the window is	183	left corner of the terminal window)- the result is pseudo-transparency:
138	moved around.	184	the image seems to be static while the window is moved around.
139		185
140	=head2 CYCLES AND CACHING	186	=head2 COLOUR SPECIFICATIONS
141		187
142	As has been mentioned before, the expression might be evaluated multiple	188	Whenever an operator expects a "colour", then this can be specified in one
143	times. Each time the expression is reevaluated, a new cycle is said to	189	of two ways: Either as string with an X11 colour specification, such as:
144	have begun. Many operators cache their results till the next cycle.
145		190
146	For example, the C<load> operator keeps a copy of the image. If it is	191	"red" # named colour
147	asked to load the same image on the next cycle it will not load it again,	192	"#f00" # simple rgb
148	but return the cached copy.	193	"[50]red" # red with 50% alpha
		194	"TekHVC:300/50/50" # anything goes
149		195
150	This only works for one cycle though, so as long as you load the same	196	OR as an array reference with one, three or four components:
151	image every time, it will always be cached, but when you load a different
152	image, it will forget about the first one.
153		197
154	This allows you to either speed things up by keeping multiple images in	198	[0.5] # 50% gray, 100% alpha
155	memory, or comserve memory by loading images more often.	199	[0.5, 0, 0] # dark red, no green or blur, 100% alpha
		200	[0.5, 0, 0, 0.7] # same with explicit 70% alpha
156		201
157	For example, you can keep two images in memory and use a random one like	202	=head2 CACHING AND SENSITIVITY
158	this:
159		203
160	my $img1 = load "img1.png";	204	Since some operations (such as C<load> and C<blur>) can take a long time,
161	my $img2 = load "img2.png";	205	caching results can be very important for a smooth operation. Caching can
162	(0.5 > rand) ? $img1 : $img2	206	also be useful to reduce memory usage, though, for example, when an image
		207	is cached by C<load>, it could be shared by multiple terminal windows
		208	running inside urxvtd.
163		209
164	Since both images are "loaded" every time the expression is evaluated,	210	=head3 C<keep { ... }> caching
165	they are always kept in memory. Contrast this version:
166		211
167	my $path1 = "img1.png";	212	The most important way to cache expensive operations is to use C<keep {
168	my $path2 = "img2.png";	213	... }>. The C<keep> operator takes a block of multiple statements enclosed
169	load ((0.5 > rand) ? $path1 : $path2)	214	by C<{}> and keeps the return value in memory.
170		215
171	Here, a path is selected randomly, and load is only called for one image,	216	An expression can be "sensitive" to various external events, such as
172	so keeps only one image in memory. If, on the next evaluation, luck	217	scaling or moving the window, root background changes and timers. Simply
173	decides to use the other path, then it will have to load that image again.	218	using an expression (such as C<scale> without parameters) that depends on
		219	certain changing values (called "variables"), or using those variables
		220	directly, will make an expression sensitive to these events - for example,
		221	using C<scale> or C<TW> will make the expression sensitive to the terminal
		222	size, and thus to resizing events.
		223
		224	When such an event happens, C<keep> will automatically trigger a
		225	reevaluation of the whole expression with the new value of the expression.
		226
		227	C<keep> is most useful for expensive operations, such as C<blur>:
		228
		229	rootalign keep { blur 20, root }
		230
		231	This makes a blurred copy of the root background once, and on subsequent
		232	calls, just root-aligns it. Since C<blur> is usually quite slow and
		233	C<rootalign> is quite fast, this trades extra memory (for the cached
		234	blurred pixmap) with speed (blur only needs to be redone when root
		235	changes).
		236
		237	=head3 C<load> caching
		238
		239	The C<load> operator itself does not keep images in memory, but as long as
		240	the image is still in memory, C<load> will use the in-memory image instead
		241	of loading it freshly from disk.
		242
		243	That means that this expression:
		244
		245	keep { load "$HOME/path..." }
		246
		247	Not only caches the image in memory, other terminal instances that try to
		248	C<load> it can reuse that in-memory copy.
174		249
175	=head1 REFERENCE	250	=head1 REFERENCE
176		251
177	=head2 COMMAND LINE SWITCHES	252	=head2 COMMAND LINE SWITCHES
178		253
…		…
188	overwriting borders and any other areas, such as the scrollbar.	263	overwriting borders and any other areas, such as the scrollbar.
189		264
190	Specifying this flag changes the behaviour, so that the image only	265	Specifying this flag changes the behaviour, so that the image only
191	replaces the background of the character area.	266	replaces the background of the character area.
192		267
		268	=item --background-interval seconds
		269
		270	Since some operations in the underlying XRender extension can effectively
		271	freeze your X-server for prolonged time, this extension enforces a minimum
		272	time between updates, which is normally about 0.1 seconds.
		273
		274	If you want to do updates more often, you can decrease this safety
		275	interval with this switch.
		276
193	=back	277	=back
194		278
195	=cut	279	=cut
196		280
		281	our %_IMG_CACHE;
197	our $HOME;	282	our $HOME;
198	our ($self, $old, $new);	283	our ($self, $frame);
199	our ($x, $y, $w, $h);	284	our ($x, $y, $w, $h, $focus);
200		285
201	# enforce at least this interval between updates	286	# enforce at least this interval between updates
202	our $MIN_INTERVAL = 1/100;	287	our $MIN_INTERVAL = 6/59.951;
203		288
204	{	289	{
205	package urxvt::bgdsl; # background language	290	package urxvt::bgdsl; # background language
		291
		292	sub FR_PARENT() { 0 } # parent frame, if any - must be #0
		293	sub FR_CACHE () { 1 } # cached values
		294	sub FR_AGAIN () { 2 } # what this expr is sensitive to
		295	sub FR_STATE () { 3 } # watchers etc.
		296
		297	use List::Util qw(min max sum shuffle);
206		298
207	=head2 PROVIDERS/GENERATORS	299	=head2 PROVIDERS/GENERATORS
208		300
209	These functions provide an image, by loading it from disk, grabbing it	301	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	302	from the root screen or by simply generating it. They are used as starting
…		…
215	=item load $path	307	=item load $path
216		308
217	Loads the image at the given C<$path>. The image is set to plane tiling	309	Loads the image at the given C<$path>. The image is set to plane tiling
218	mode.	310	mode.
219		311
220	Loaded images will be cached for one cycle.	312	If the image is already in memory (e.g. because another terminal instance
		313	uses it), then the in-memory copy is returned instead.
221		314
		315	=item load_uc $path
		316
		317	Load uncached - same as load, but does not cache the image, which means it
		318	is I<always> loaded from the filesystem again, even if another copy of it
		319	is in memory at the time.
		320
222	=cut	321	=cut
		322
		323	sub load_uc($) {
		324	$self->new_img_from_file ($_[0])
		325	}
223		326
224	sub load($) {	327	sub load($) {
225	my ($path) = @_;	328	my ($path) = @_;
226		329
227	$new->{load}{$path} = $old->{load}{$path} \|\| $self->new_img_from_file ($path);	330	$_IMG_CACHE{$path} \|\| do {
		331	my $img = load_uc $path;
		332	Scalar::Util::weaken ($_IMG_CACHE{$path} = $img);
		333	$img
		334	}
228	}	335	}
229		336
230	=item root	337	=item root
231		338
232	Returns the root window pixmap, that is, hopefully, the background image	339	Returns the root window pixmap, that is, hopefully, the background image
233	of your screen. The image is set to extend mode.	340	of your screen.
234		341
235	This function makes your expression root sensitive, that means it will be	342	This function makes your expression root sensitive, that means it will be
236	reevaluated when the bg image changes.	343	reevaluated when the bg image changes.
237		344
238	=cut	345	=cut
239		346
240	sub root() {	347	sub root() {
241	$new->{rootpmap_sensitive} = 1;	348	$frame->[FR_AGAIN]{rootpmap} = 1;
242	die "root op not supported, exg, we need you";	349	$self->new_img_from_root
243	}	350	}
244		351
245	=item solid $colour	352	=item solid $colour
246		353
247	=item solid $width, $height, $colour	354	=item solid $width, $height, $colour
…		…
255	=cut	362	=cut
256		363
257	sub solid($;$$) {	364	sub solid($;$$) {
258	my $colour = pop;	365	my $colour = pop;
259		366
260	my $img = $self->new_img (urxvt::PictStandardARGB32, $_[0] \|\| 1, $_[1] \|\| 1);	367	my $img = $self->new_img (urxvt::PictStandardARGB32, 0, 0, $_[0] \|\| 1, $_[1] \|\| 1);
261	$img->fill ($colour);	368	$img->fill ($colour);
262	$img	369	$img
263	}	370	}
264		371
265	=back	372	=item clone $img
266		373
267	=head2 VARIABLES	374	Returns an exact copy of the image. This is useful if you want to have
		375	multiple copies of the same image to apply different effects to.
268		376
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	377	=cut
311		378
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} = $_[0];
345	}
346
347	sub counter($) {	379	sub clone($) {
348	$new->{again} = $_[0];	380	$_[0]->clone
349	$self->{counter} + 0	381	}
		382
		383	=item merge $img ...
		384
		385	Takes any number of images and merges them together, creating a single
		386	image containing them all. The tiling mode of the first image is used as
		387	the tiling mode of the resulting image.
		388
		389	This function is called automatically when an expression returns multiple
		390	images.
		391
		392	=cut
		393
		394	sub merge(@) {
		395	return $_[0] unless $#_;
		396
		397	# rather annoyingly clumsy, but optimisation is for another time
		398
		399	my $x0 = +1e9;
		400	my $y0 = +1e9;
		401	my $x1 = -1e9;
		402	my $y1 = -1e9;
		403
		404	for (@_) {
		405	my ($x, $y, $w, $h) = $_->geometry;
		406
		407	$x0 = $x if $x0 > $x;
		408	$y0 = $y if $y0 > $y;
		409
		410	$x += $w;
		411	$y += $h;
		412
		413	$x1 = $x if $x1 < $x;
		414	$y1 = $y if $y1 < $y;
		415	}
		416
		417	my $base = $self->new_img (urxvt::PictStandardARGB32, $x0, $y0, $x1 - $x0, $y1 - $y0);
		418	$base->repeat_mode ($_[0]->repeat_mode);
		419	$base->fill ([0, 0, 0, 0]);
		420
		421	$base->draw ($_)
		422	for @_;
		423
		424	$base
350	}	425	}
351		426
352	=back	427	=back
353		428
354	=head2 TILING MODES	429	=head2 TILING MODES
…		…
387	become transparent. This mode is most useful when you want to place an	462	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	463	image over another image or the background colour while leaving all
389	background pixels outside the image unchanged.	464	background pixels outside the image unchanged.
390		465
391	Example: load an image and display it in the upper left corner. The rest	466	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	467	of the space is left "empty" (transparent or whatever your compositor does
393	in alpha mode, else background colour).	468	in alpha mode, else background colour).
394		469
395	pad load "mybg.png"	470	pad load "mybg.png"
396		471
397	=item extend $img	472	=item extend $img
398		473
399	Extends the image over the whole plane, using the closest pixel in the	474	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	475	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	476	filtering operations and want the pixels outside the image to have the
402	same values as the pixels near the edge.	477	same values as the pixels near the edge.
403		478
404	Example: just for curiosity, how does this pixel extension stuff work?	479	Example: just for curiosity, how does this pixel extension stuff work?
405		480
…		…
431	$img	506	$img
432	}	507	}
433		508
434	=back	509	=back
435		510
436	=head2 PIXEL OPERATORS	511	=head2 VARIABLE VALUES
437		512
438	The following operators modify the image pixels in various ways.	513	The following functions provide variable data such as the terminal window
		514	dimensions. They are not (Perl-) variables, they just return stuff that
		515	varies. Most of them make your expression sensitive to some events, for
		516	example using C<TW> (terminal width) means your expression is evaluated
		517	again when the terminal is resized.
439		518
440	=over 4	519	=over 4
441		520
442	=item clone $img	521	=item TX
443		522
444	Returns an exact copy of the image.	523	=item TY
445		524
446	=cut	525	Return the X and Y coordinates of the terminal window (the terminal
		526	window is the full window by default, and the character area only when in
		527	border-respect mode).
447		528
		529	Using these functions makes your expression sensitive to window moves.
		530
		531	These functions are mainly useful to align images to the root window.
		532
		533	Example: load an image and align it so it looks as if anchored to the
		534	background (that's exactly what C<rootalign> does btw.):
		535
		536	move -TX, -TY, keep { load "mybg.png" }
		537
		538	=item TW
		539
		540	=item TH
		541
		542	Return the width (C<TW>) and height (C<TH>) of the terminal window (the
		543	terminal window is the full window by default, and the character area only
		544	when in border-respect mode).
		545
		546	Using these functions makes your expression sensitive to window resizes.
		547
		548	These functions are mainly useful to scale images, or to clip images to
		549	the window size to conserve memory.
		550
		551	Example: take the screen background, clip it to the window size, blur it a
		552	bit, align it to the window position and use it as background.
		553
		554	clip move -TX, -TY, keep { blur 5, root }
		555
		556	=item FOCUS
		557
		558	Returns a boolean indicating whether the terminal window has keyboard
		559	focus, in which case it returns true.
		560
		561	Using this function makes your expression sensitive to focus changes.
		562
		563	A common use case is to fade the background image when the terminal loses
		564	focus, often together with the C<-fade> command line option. In fact,
		565	there is a special function for just that use case: C<focus_fade>.
		566
		567	Example: use two entirely different background images, depending on
		568	whether the window has focus.
		569
		570	FOCUS ? keep { load "has_focus.jpg" } : keep { load "no_focus.jpg" }
		571
		572	=cut
		573
		574	sub TX () { $frame->[FR_AGAIN]{position} = 1; $x }
		575	sub TY () { $frame->[FR_AGAIN]{position} = 1; $y }
		576	sub TW () { $frame->[FR_AGAIN]{size} = 1; $w }
		577	sub TH () { $frame->[FR_AGAIN]{size} = 1; $h }
		578	sub FOCUS() { $frame->[FR_AGAIN]{focus} = 1; $focus }
		579
		580	=item now
		581
		582	Returns the current time as (fractional) seconds since the epoch.
		583
		584	Using this expression does I<not> make your expression sensitive to time,
		585	but the next two functions do.
		586
		587	=item again $seconds
		588
		589	When this function is used the expression will be reevaluated again in
		590	C<$seconds> seconds.
		591
		592	Example: load some image and rotate it according to the time of day (as if it were
		593	the hour pointer of a clock). Update this image every minute.
		594
		595	again 60;
		596	rotate 50, 50, (now % 86400) * -72 / 8640, scale keep { load "myclock.png" }
		597
		598	=item counter $seconds
		599
		600	Like C<again>, but also returns an increasing counter value, starting at
		601	0, which might be useful for some simple animation effects.
		602
		603	=cut
		604
		605	sub now() { urxvt::NOW }
		606
		607	sub again($) {
		608	$frame->[FR_AGAIN]{time} = $_[0];
		609	}
		610
448	sub clone($) {	611	sub counter($) {
449	$_[0]->clone	612	$frame->[FR_AGAIN]{time} = $_[0];
		613	$frame->[FR_STATE]{counter} + 0
450	}	614	}
		615
		616	=back
		617
		618	=head2 SHAPE CHANGING OPERATORS
		619
		620	The following operators modify the shape, size or position of the image.
		621
		622	=over 4
451		623
452	=item clip $img	624	=item clip $img
453		625
454	=item clip $width, $height, $img	626	=item clip $width, $height, $img
455		627
…		…
458	Clips an image to the given rectangle. If the rectangle is outside the	630	Clips an image to the given rectangle. If the rectangle is outside the
459	image area (e.g. when C<$x> or C<$y> are negative) or the rectangle is	631	image area (e.g. when C<$x> or C<$y> are negative) or the rectangle is
460	larger than the image, then the tiling mode defines how the extra pixels	632	larger than the image, then the tiling mode defines how the extra pixels
461	will be filled.	633	will be filled.
462		634
463	If C<$x> an C<$y> are missing, then C<0> is assumed for both.	635	If C<$x> and C<$y> are missing, then C<0> is assumed for both.
464		636
465	If C<$width> and C<$height> are missing, then the window size will be	637	If C<$width> and C<$height> are missing, then the window size will be
466	assumed.	638	assumed.
467		639
468	Example: load an image, blur it, and clip it to the window size to save	640	Example: load an image, blur it, and clip it to the window size to save
469	memory.	641	memory.
470		642
471	clip blur 10, load "mybg.png"	643	clip keep { blur 10, load "mybg.png" }
472		644
473	=cut	645	=cut
474		646
475	sub clip($;$$;$$) {	647	sub clip($;$$;$$) {
476	my $img = pop;	648	my $img = pop;
…		…
479	$img->sub_rect ($_[0], $_[1], $w, $h)	651	$img->sub_rect ($_[0], $_[1], $w, $h)
480	}	652	}
481		653
482	=item scale $img	654	=item scale $img
483		655
484	=item scale $size_percent, $img	656	=item scale $size_factor, $img
485		657
486	=item scale $width_percent, $height_percent, $img	658	=item scale $width_factor, $height_factor, $img
487		659
488	Scales the image by the given percentages in horizontal	660	Scales the image by the given factors in horizontal
489	(C<$width_percent>) and vertical (C<$height_percent>) direction.	661	(C<$width>) and vertical (C<$height>) direction.
490		662
491	If only one percentage is give, it is used for both directions.	663	If only one factor is given, it is used for both directions.
492		664
493	If no percentages are given, scales the image to the window size without	665	If no factors are given, scales the image to the window size without
494	keeping aspect.	666	keeping aspect.
495		667
496	=item resize $width, $height, $img	668	=item resize $width, $height, $img
497		669
498	Resizes the image to exactly C<$width> times C<$height> pixels.	670	Resizes the image to exactly C<$width> times C<$height> pixels.
499		671
500	=cut	672	=item fit $img
501		673
502	#TODO: maximise, maximise_fill?	674	=item fit $width, $height, $img
		675
		676	Fits the image into the given C<$width> and C<$height> without changing
		677	aspect, or the terminal size. That means it will be shrunk or grown until
		678	the whole image fits into the given area, possibly leaving borders.
		679
		680	=item cover $img
		681
		682	=item cover $width, $height, $img
		683
		684	Similar to C<fit>, but shrinks or grows until all of the area is covered
		685	by the image, so instead of potentially leaving borders, it will cut off
		686	image data that doesn't fit.
		687
		688	=cut
503		689
504	sub scale($;$;$) {	690	sub scale($;$;$) {
505	my $img = pop;	691	my $img = pop;
506		692
507	@_ == 2 ? $img->scale ($_[0] * $img->w * 0.01, $_[1] * $img->h * 0.01)	693	@_ == 2 ? $img->scale ($_[0] * $img->w, $_[1] * $img->h)
508	: @_ ? $img->scale ($_[0] * $img->w * 0.01, $_[0] * $img->h * 0.01)	694	: @_ ? $img->scale ($_[0] * $img->w, $_[0] * $img->h)
509	: $img->scale (TW, TH)	695	: $img->scale (TW, TH)
510	}	696	}
511		697
512	sub resize($$$) {	698	sub resize($$$) {
513	my $img = pop;	699	my $img = pop;
514	$img->scale ($_[0], $_[1])	700	$img->scale ($_[0], $_[1])
515	}	701	}
516		702
		703	sub fit($;$$) {
		704	my $img = pop;
		705	my $w = ($_[0] \|\| TW) / $img->w;
		706	my $h = ($_[1] \|\| TH) / $img->h;
		707	scale +(min $w, $h), $img
		708	}
		709
		710	sub cover($;$$) {
		711	my $img = pop;
		712	my $w = ($_[0] \|\| TW) / $img->w;
		713	my $h = ($_[1] \|\| TH) / $img->h;
		714	scale +(max $w, $h), $img
		715	}
		716
517	=item move $dx, $dy, $img	717	=item move $dx, $dy, $img
518		718
519	Moves the image by C<$dx> pixels in the horizontal, and C<$dy> pixels in	719	Moves the image by C<$dx> pixels in the horizontal, and C<$dy> pixels in
520	the vertical.	720	the vertical.
521		721
522	Example: move the image right by 20 pixels and down by 30.	722	Example: move the image right by 20 pixels and down by 30.
523		723
524	move 20, 30, ...	724	move 20, 30, ...
		725
		726	=item align $xalign, $yalign, $img
		727
		728	Aligns the image according to a factor - C<0> means the image is moved to
		729	the left or top edge (for C<$xalign> or C<$yalign>), C<0.5> means it is
		730	exactly centered and C<1> means it touches the right or bottom edge.
		731
		732	Example: remove any visible border around an image, center it vertically but move
		733	it to the right hand side.
		734
		735	align 1, 0.5, pad $img
		736
		737	=item center $img
		738
		739	=item center $width, $height, $img
		740
		741	Centers the image, i.e. the center of the image is moved to the center of
		742	the terminal window (or the box specified by C<$width> and C<$height> if
		743	given).
		744
		745	Example: load an image and center it.
		746
		747	center keep { pad load "mybg.png" }
525		748
526	=item rootalign $img	749	=item rootalign $img
527		750
528	Moves the image so that it appears glued to the screen as opposed to the	751	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	752	window. This gives the illusion of a larger area behind the window. It is
530	exactly equivalent to C<move -TX, -TY>, that is, it moves the image to the	753	exactly equivalent to C<move -TX, -TY>, that is, it moves the image to the
531	top left of the screen.	754	top left of the screen.
532		755
533	Example: load a background image, put it in mirror mode and root align it.	756	Example: load a background image, put it in mirror mode and root align it.
534		757
535	rootalign mirror load "mybg.png"	758	rootalign keep { mirror load "mybg.png" }
536		759
537	Example: take the screen background and align it, giving the illusion of	760	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.	761	transparency as long as the window isn't in front of other windows.
539		762
540	rootalign root	763	rootalign root
541		764
542	=cut	765	=cut
543		766
544	sub move($$;$) {	767	sub move($$;$) {
545	my $img = pop->clone;	768	my $img = pop->clone;
546	$img->move ($_[0], $_[1]);	769	$img->move ($_[0], $_[1]);
547	$img	770	$img
548	}	771	}
549		772
		773	sub align($;$$) {
		774	my $img = pop;
		775
		776	move $_[0] * (TW - $img->w),
		777	$_[1] * (TH - $img->h),
		778	$img
		779	}
		780
		781	sub center($;$$) {
		782	my $img = pop;
		783	my $w = $_[0] \|\| TW;
		784	my $h = $_[1] \|\| TH;
		785
		786	move 0.5 * ($w - $img->w), 0.5 * ($h - $img->h), $img
		787	}
		788
550	sub rootalign($) {	789	sub rootalign($) {
551	move -TX, -TY, $_[0]	790	move -TX, -TY, $_[0]
552	}	791	}
553		792
		793	=item rotate $center_x, $center_y, $degrees, $img
		794
		795	Rotates the image clockwise by C<$degrees> degrees, around the point at
		796	C<$center_x> and C<$center_y> (specified as factor of image width/height).
		797
		798	Example: rotate the image by 90 degrees around its center.
		799
		800	rotate 0.5, 0.5, 90, keep { load "$HOME/mybg.png" }
		801
		802	=cut
		803
		804	sub rotate($$$$) {
		805	my $img = pop;
		806	$img->rotate (
		807	$_[0] * ($img->w + $img->x),
		808	$_[1] * ($img->h + $img->y),
		809	$_[2] * (3.14159265 / 180),
		810	)
		811	}
		812
		813	=back
		814
		815	=head2 COLOUR MODIFICATIONS
		816
		817	The following operators change the pixels of the image.
		818
		819	=over 4
		820
		821	=item tint $color, $img
		822
		823	Tints the image in the given colour.
		824
		825	Example: tint the image red.
		826
		827	tint "red", load "rgb.png"
		828
		829	Example: the same, but specify the colour by component.
		830
		831	tint [1, 0, 0], load "rgb.png"
		832
		833	=cut
		834
		835	sub tint($$) {
		836	$_[1]->tint ($_[0])
		837	}
		838
		839	=item shade $factor, $img
		840
		841	Shade the image by the given factor.
		842
		843	=cut
		844
		845	sub shade($$) {
		846	$_[1]->shade ($_[0])
		847	}
		848
554	=item contrast $factor, $img	849	=item contrast $factor, $img
555		850
556	=item contrast $r, $g, $b, $img	851	=item contrast $r, $g, $b, $img
557		852
558	=item contrast $r, $g, $b, $a, $img	853	=item contrast $r, $g, $b, $a, $img
559		854
560	Adjusts the I<contrast> of an image.	855	Adjusts the I<contrast> of an image.
561		856
562	#TODO#	857	The first form applies a single C<$factor> to red, green and blue, the
		858	second form applies separate factors to each colour channel, and the last
		859	form includes the alpha channel.
563		860
		861	Values from 0 to 1 lower the contrast, values higher than 1 increase the
		862	contrast.
		863
		864	Due to limitations in the underlying XRender extension, lowering contrast
		865	also reduces brightness, while increasing contrast currently also
		866	increases brightness.
		867
564	=item brightness $factor, $img	868	=item brightness $bias, $img
565		869
566	=item brightness $r, $g, $b, $img	870	=item brightness $r, $g, $b, $img
567		871
568	=item brightness $r, $g, $b, $a, $img	872	=item brightness $r, $g, $b, $a, $img
569		873
570	Adjusts the brightness of an image.	874	Adjusts the brightness of an image.
		875
		876	The first form applies a single C<$bias> to red, green and blue, the
		877	second form applies separate biases to each colour channel, and the last
		878	form includes the alpha channel.
		879
		880	Values less than 0 reduce brightness, while values larger than 0 increase
		881	it. Useful range is from -1 to 1 - the former results in a black, the
		882	latter in a white picture.
		883
		884	Due to idiosyncrasies in the underlying XRender extension, biases less
		885	than zero can be I<very> slow.
		886
		887	You can also try the experimental(!) C<muladd> operator.
571		888
572	=cut	889	=cut
573		890
574	sub contrast($$;$$;$) {	891	sub contrast($$;$$;$) {
575	my $img = pop;	892	my $img = pop;
576	my ($r, $g, $b, $a) = @_;	893	my ($r, $g, $b, $a) = @_;
577		894
578	($g, $b) = ($r, $r) if @_ < 4;	895	($g, $b) = ($r, $r) if @_ < 3;
579	$a = 1 if @_ < 5;	896	$a = 1 if @_ < 4;
580		897
581	$img = $img->clone;	898	$img = $img->clone;
582	$img->contrast ($r, $g, $b, $a);	899	$img->contrast ($r, $g, $b, $a);
583	$img	900	$img
584	}	901	}
585		902
586	sub brightness($$;$$;$) {	903	sub brightness($$;$$;$) {
587	my $img = pop;	904	my $img = pop;
588	my ($r, $g, $b, $a) = @_;	905	my ($r, $g, $b, $a) = @_;
589		906
590	($g, $b) = ($r, $r) if @_ < 4;	907	($g, $b) = ($r, $r) if @_ < 3;
591	$a = 1 if @_ < 5;	908	$a = 1 if @_ < 4;
592		909
593	$img = $img->clone;	910	$img = $img->clone;
594	$img->brightness ($r, $g, $b, $a);	911	$img->brightness ($r, $g, $b, $a);
595	$img	912	$img
		913	}
		914
		915	=item muladd $mul, $add, $img # EXPERIMENTAL
		916
		917	First multiplies the pixels by C<$mul>, then adds C<$add>. This can be used
		918	to implement brightness and contrast at the same time, with a wider value
		919	range than contrast and brightness operators.
		920
		921	Due to numerous bugs in XRender implementations, it can also introduce a
		922	number of visual artifacts.
		923
		924	Example: increase contrast by a factor of C<$c> without changing image
		925	brightness too much.
		926
		927	muladd $c, (1 - $c) * 0.5, $img
		928
		929	=cut
		930
		931	sub muladd($$$) {
		932	$_[2]->muladd ($_[0], $_[1])
596	}	933	}
597		934
598	=item blur $radius, $img	935	=item blur $radius, $img
599		936
600	=item blur $radius_horz, $radius_vert, $img	937	=item blur $radius_horz, $radius_vert, $img
…		…
612	sub blur($$;$) {	949	sub blur($$;$) {
613	my $img = pop;	950	my $img = pop;
614	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])	951	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])
615	}	952	}
616		953
617	=item rotate $new_width, $new_height, $center_x, $center_y, $degrees	954	=item focus_fade $img
618		955
619	Rotates the image by C<$degrees> degrees, counter-clockwise, around the	956	=item focus_fade $factor, $img
620	pointer at C<$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		957
624	#TODO# new width, height, maybe more operators?	958	=item focus_fade $factor, $color, $img
625		959
626	Example: rotate the image by 90 degrees	960	Fades the image by the given factor (and colour) when focus is lost (the
		961	same as the C<-fade>/C<-fadecolor> command line options, which also supply
		962	the default values for C<factor> and C<$color>. Unlike with C<-fade>, the
		963	C<$factor> is the real value, not a percentage value (that is, 0..1, not
		964	0..100).
627		965
628	=cut	966	Example: do the right thing when focus fading is requested.
629		967
630	sub rotate($$$$$$) {	968	focus_fade load "mybg.jpg";
		969
		970	=cut
		971
		972	sub focus_fade($;$$) {
631	my $img = pop;	973	my $img = pop;
632	$img->rotate (	974
633	$_[0],	975	return $img
634	$_[1],	976	if FOCUS;
635	$_[2] * $img->w * .01,	977
636	$_[3] * $img->h * .01,	978	my $fade = @_ >= 1 ? $_[0] : defined $self->resource ("fade") ? $self->resource ("fade") * 0.01 : 0;
637	$_[4] * (3.14159265 / 180),	979	my $color = @_ >= 2 ? $_[1] : $self->resource ("color+" . urxvt::Color_fade);
638	)	980
		981	$img = $img->tint ($color) if $color ne "rgb:00/00/00";
		982	$img = $img->muladd (1 - $fade, 0) if $fade;
		983
		984	$img
639	}	985	}
640		986
641	=back	987	=back
642		988
		989	=head2 OTHER STUFF
		990
		991	Anything that didn't fit any of the other categories, even after applying
		992	force and closing our eyes.
		993
		994	=over 4
		995
		996	=item keep { ... }
		997
		998	This operator takes a code block as argument, that is, one or more
		999	statements enclosed by braces.
		1000
		1001	The trick is that this code block is only evaluated when the outcome
		1002	changes - on other calls the C<keep> simply returns the image it computed
		1003	previously (yes, it should only be used with images). Or in other words,
		1004	C<keep> I<caches> the result of the code block so it doesn't need to be
		1005	computed again.
		1006
		1007	This can be extremely useful to avoid redoing slow operations - for
		1008	example, if your background expression takes the root background, blurs it
		1009	and then root-aligns it it would have to blur the root background on every
		1010	window move or resize.
		1011
		1012	Another example is C<load>, which can be quite slow.
		1013
		1014	In fact, urxvt itself encloses the whole expression in some kind of
		1015	C<keep> block so it only is reevaluated as required.
		1016
		1017	Putting the blur into a C<keep> block will make sure the blur is only done
		1018	once, while the C<rootalign> is still done each time the window moves.
		1019
		1020	rootalign keep { blur 10, root }
		1021
		1022	This leaves the question of how to force reevaluation of the block,
		1023	in case the root background changes: If expression inside the block
		1024	is sensitive to some event (root background changes, window geometry
		1025	changes), then it will be reevaluated automatically as needed.
		1026
		1027	=cut
		1028
		1029	sub keep(&) {
		1030	my $id = $_[0]+0;
		1031
		1032	local $frame = $self->{frame_cache}{$id} \|\|= [$frame];
		1033
		1034	unless ($frame->[FR_CACHE]) {
		1035	$frame->[FR_CACHE] = [ $_[0]() ];
		1036
		1037	my $self = $self;
		1038	my $frame = $frame;
		1039	Scalar::Util::weaken $frame;
		1040	$self->compile_frame ($frame, sub {
		1041	# clear this frame cache, also for all parents
		1042	for (my $frame = $frame; $frame; $frame = $frame->[0]) {
		1043	undef $frame->[FR_CACHE];
		1044	}
		1045
		1046	$self->recalculate;
		1047	});
		1048	};
		1049
		1050	# in scalar context we always return the first original result, which
		1051	# is not quite how perl works.
		1052	wantarray
		1053	? @{ $frame->[FR_CACHE] }
		1054	: $frame->[FR_CACHE][0]
		1055	}
		1056
		1057	# sub keep_clear() {
		1058	# delete $self->{frame_cache};
		1059	# }
		1060
		1061	=back
		1062
643	=cut	1063	=cut
644		1064
645	}	1065	}
646		1066
647	sub parse_expr {	1067	sub parse_expr {
648	my $expr = eval "sub {\npackage urxvt::bgdsl;\n#line 0 'background expression'\n$_[0]\n}";	1068	my $expr = eval
		1069	"sub {\n"
		1070	. "package urxvt::bgdsl;\n"
		1071	. "#line 0 'background expression'\n"
		1072	. "$_[0]\n"
		1073	. "}";
649	die if $@;	1074	die if $@;
650	$expr	1075	$expr
651	}	1076	}
652		1077
653	# compiles a parsed expression	1078	# compiles a parsed expression
654	sub set_expr {	1079	sub set_expr {
655	my ($self, $expr) = @_;	1080	my ($self, $expr) = @_;
656		1081
		1082	$self->{root} = []; # the outermost frame
657	$self->{expr} = $expr;	1083	$self->{expr} = $expr;
658	$self->recalculate;	1084	$self->recalculate;
		1085	}
		1086
		1087	# takes a hash of sensitivity indicators and installs watchers
		1088	sub compile_frame {
		1089	my ($self, $frame, $cb) = @_;
		1090
		1091	my $state = $frame->[urxvt::bgdsl::FR_STATE] \|\|= {};
		1092	my $again = $frame->[urxvt::bgdsl::FR_AGAIN];
		1093
		1094	# don't keep stuff alive
		1095	Scalar::Util::weaken $state;
		1096
		1097	if ($again->{nested}) {
		1098	$state->{nested} = 1;
		1099	} else {
		1100	delete $state->{nested};
		1101	}
		1102
		1103	if (my $interval = $again->{time}) {
		1104	$state->{time} = [$interval, urxvt::timer->new->after ($interval)->interval ($interval)]
		1105	if $state->{time}[0] != $interval;
		1106
		1107	# callback might have changed, although we could just rule that out
		1108	$state->{time}[1]->cb (sub {
		1109	++$state->{counter};
		1110	$cb->();
		1111	});
		1112	} else {
		1113	delete $state->{time};
		1114	}
		1115
		1116	if ($again->{position}) {
		1117	$state->{position} = $self->on (position_change => $cb);
		1118	} else {
		1119	delete $state->{position};
		1120	}
		1121
		1122	if ($again->{size}) {
		1123	$state->{size} = $self->on (size_change => $cb);
		1124	} else {
		1125	delete $state->{size};
		1126	}
		1127
		1128	if ($again->{rootpmap}) {
		1129	$state->{rootpmap} = $self->on (rootpmap_change => $cb);
		1130	} else {
		1131	delete $state->{rootpmap};
		1132	}
		1133
		1134	if ($again->{focus}) {
		1135	$state->{focus} = $self->on (focus_in => $cb, focus_out => $cb);
		1136	} else {
		1137	delete $state->{focus};
		1138	}
659	}	1139	}
660		1140
661	# evaluate the current bg expression	1141	# evaluate the current bg expression
662	sub recalculate {	1142	sub recalculate {
663	my ($arg_self) = @_;	1143	my ($arg_self) = @_;
…		…
673		1153
674	$arg_self->{next_refresh} = urxvt::NOW + $MIN_INTERVAL;	1154	$arg_self->{next_refresh} = urxvt::NOW + $MIN_INTERVAL;
675		1155
676	# set environment to evaluate user expression	1156	# set environment to evaluate user expression
677		1157
678	local $self = $arg_self;	1158	local $self = $arg_self;
679
680	local $HOME = $ENV{HOME};	1159	local $HOME = $ENV{HOME};
681	local $old = $self->{state};	1160	local $frame = $self->{root};
682	local $new = my $state = $self->{state} = {};
683		1161
684	($x, $y, $w, $h) =
685	$self->background_geometry ($self->{border});	1162	($x, $y, $w, $h) = $self->background_geometry ($self->{border});
		1163	$focus = $self->focus;
686		1164
687	# evaluate user expression	1165	# evaluate user expression
688		1166
689	my $img = eval { $self->{expr}->() };	1167	my @img = eval { $self->{expr}->() };
690	warn $@ if $@;#d#	1168	die $@ if $@;
		1169	die "background-expr did not return anything.\n" unless @img;
		1170	die "background-expr: expected image(s), got something else.\n"
691	die if !UNIVERSAL::isa $img, "urxvt::img";	1171	if grep { !UNIVERSAL::isa $_, "urxvt::img" } @img;
692		1172
693	$state->{size_sensitive} = 1	1173	my $img = urxvt::bgdsl::merge @img;
		1174
		1175	$frame->[FR_AGAIN]{size} = 1
694	if $img->repeat_mode != urxvt::RepeatNormal;	1176	if $img->repeat_mode != urxvt::RepeatNormal;
695		1177
696	# if the expression is sensitive to external events, prepare reevaluation then	1178	# if the expression is sensitive to external events, prepare reevaluation then
697		1179	$self->compile_frame ($frame, sub { $arg_self->recalculate });
698	my $repeat;
699
700	if (my $again = $state->{again}) {
701	$repeat = 1;
702	my $self = $self;
703	$state->{timer} = $again == $old->{again}
704	? $old->{timer}
705	: urxvt::timer->new->after ($again)->interval ($again)->cb (sub {
706	++$self->{counter};
707	$self->recalculate
708	});
709	}
710
711	if (delete $state->{position_sensitive}) {
712	$repeat = 1;
713	$self->enable (position_change => sub { $_[0]->recalculate });
714	} else {
715	$self->disable ("position_change");
716	}
717
718	if (delete $state->{size_sensitive}) {
719	$repeat = 1;
720	$self->enable (size_change => sub { $_[0]->recalculate });
721	} else {
722	$self->disable ("size_change");
723	}
724
725	if (delete $state->{rootpmap_sensitive}) {
726	$repeat = 1;
727	$self->enable (rootpmap_change => sub { $_[0]->recalculate });
728	} else {
729	$self->disable ("rootpmap_change");
730	}
731		1180
732	# clear stuff we no longer need	1181	# clear stuff we no longer need
733		1182
734	%$old = ();	1183	# unless (%{ $frame->[FR_STATE] }) {
735
736	unless ($repeat) {
737	delete $self->{state};	1184	# delete $self->{state};
738	delete $self->{expr};	1185	# delete $self->{expr};
739	}	1186	# }
740		1187
741	# set background pixmap	1188	# set background pixmap
742		1189
743	$self->set_background ($img, $self->{border});	1190	$self->set_background ($img, $self->{border});
744	$self->scr_recolour (0);	1191	$self->scr_recolour (0);
…		…
746	}	1193	}
747		1194
748	sub on_start {	1195	sub on_start {
749	my ($self) = @_;	1196	my ($self) = @_;
750		1197
751	my $expr = $self->x_resource ("background.expr")	1198	my $expr = $self->x_resource ("%.expr")
752	or return;	1199	or return;
753		1200
		1201	$self->has_render
		1202	or die "background extension needs RENDER extension 0.10 or higher, ignoring background-expr.\n";
		1203
754	$self->set_expr (parse_expr $expr);	1204	$self->set_expr (parse_expr $expr);
755	$self->{border} = $self->x_resource_boolean ("background.border");	1205	$self->{border} = $self->x_resource_boolean ("%.border");
		1206
		1207	$MIN_INTERVAL = $self->x_resource ("%.interval");
756		1208
757	()	1209	()
758	}	1210	}
759		1211

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Comparing rxvt-unicode/src/perl/background (file contents): Revision 1.42 by root, Sun Jun 10 10:42:19 2012 UTC vs. Revision 1.86 by sf-exg, Fri Oct 4 17:09:57 2013 UTC

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Comparing rxvt-unicode/src/perl/background (file contents):
Revision 1.42 by root, Sun Jun 10 10:42:19 2012 UTC vs.
Revision 1.86 by sf-exg, Fri Oct 4 17:09:57 2013 UTC