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

Comparing rxvt-unicode/src/perl/background (file contents):
Revision 1.35 by root, Fri Jun 8 08:06:38 2012 UTC vs.
Revision 1.45 by root, Sun Jun 10 11:53:32 2012 UTC

…		…
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
6	#TODO: once, rootalign	6	#TODO: once, rootalign
7		7
		8	=head1 NAME
		9
8	=head1 background - manage terminal background	10	background - manage terminal background
9		11
10	=head2 SYNOPSIS	12	=head1 SYNOPSIS
11		13
12	rxvt -background-expr 'background expression'	14	urxvt --background-expr 'background expression'
13	-background-border	15	--background-border
14		16
15	=head2 DESCRIPTION	17	=head1 DESCRIPTION
16		18
		19	This extension manages the terminal background by creating a picture that
		20	is behind the text, replacing the normal background colour.
		21
		22	It does so by evaluating a Perl expression that I<calculates> the image on
		23	the fly, for example, by grabbing the root background or loading a file.
		24
		25	While the full power of Perl is available, the operators have been design
		26	to be as simple as possible.
		27
		28	For example, to load an image and scale it to the window size, you would
		29	use:
		30
		31	urxvt --background-expr 'scale load "/path/to/mybg.png"'
		32
		33	Or specified as a X resource:
		34
		35	URxvt.background-expr: scale load "/path/to/mybg.png"
		36
		37	=head1 THEORY OF OPERATION
		38
		39	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
		41	extended as necessary to cover the whole terminal window, and is set as a
		42	background pixmap.
		43
		44	If the image contains an alpha channel, then it will be used as-is in
		45	visuals that support alpha channels (for example, for a compositing
		46	manager). In other visuals, the terminal background colour will be used to
		47	replace any transparency.
		48
		49	When the expression relies, directly or indirectly, on the window size,
		50	position, the root pixmap, or a timer, then it will be remembered. If not,
		51	then it will be removed.
		52
		53	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
		55	pixmap is replaced by another one the root background changes; or when the
		56	timer elapses), then the expression will be evaluated again.
		57
		58	For example, an expression such as C<scale load "$HOME/mybg.png"> scales the
		59	image to the window size, so it relies on the window size and will
		60	be reevaluated each time it is changed, but not when it moves for
		61	example. That ensures that the picture always fills the terminal, even
		62	after it's size changes.
		63
		64	=head2 EXPRESSIONS
		65
		66	Expressions are normal Perl expressions, in fact, they are Perl blocks -
		67	which means you could use multiple lines and statements:
		68
		69	again 3600;
		70	if (localtime now)[6]) {
		71	return scale load "$HOME/weekday.png";
		72	} else {
		73	return scale load "$HOME/sunday.png";
		74	}
		75
		76	This expression gets evaluated once per hour. It will set F<sunday.png> as
		77	background on Sundays, and F<weekday.png> on all other days.
		78
		79	Fortunately, we expect that most expressions will be much simpler, with
		80	little Perl knowledge needed.
		81
		82	Basically, you always start with a function that "generates" an image
		83	object, such as C<load>, which loads an image from disk, or C<root>, which
		84	returns the root window background image:
		85
		86	load "$HOME/mypic.png"
		87
		88	The path is usually specified as a quoted string (the exact rules can be
		89	found in the L<perlop> manpage). The F<$HOME> at the beginning of the
		90	string is expanded to the home directory.
		91
		92	Then you prepend one or more modifiers or filtering expressions, such as
		93	C<scale>:
		94
		95	scale load "$HOME/mypic.png"
		96
		97	Just like a mathematical expression with functions, you should read these
		98	expressions from right to left, as the C<load> is evaluated first, and
		99	its result becomes the argument to the C<scale> function.
		100
		101	Many operators also allow some parameters preceding the input image
		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
		104	an additional argument, it uses it as a scale factor (multiply by 100 to
		105	get a percentage):
		106
		107	scale 2, load "$HOME/mypic.png"
		108
		109	This enlarges the image by a factor of 2 (200%). As you can see, C<scale>
		110	has now two arguments, the C<200> and the C<load> expression, while
		111	C<load> only has one argument. Arguments are separated from each other by
		112	commas.
		113
		114	Scale also accepts two arguments, which are then separate factors for both
		115	horizontal and vertical dimensions. For example, this halves the image
		116	width and doubles the image height:
		117
		118	scale 0.5, 2, load "$HOME/mypic.png"
		119
		120	Other effects than scalign are also readily available, for exmaple, you can
		121	tile the image to fill the whole window, instead of resizing it:
		122
		123	tile load "$HOME/mypic.png"
		124
		125	In fact, images returned by C<load> are in C<tile> mode by default, so the C<tile> operator
		126	is kind of superfluous.
		127
		128	Another common effect is to mirror the image, so that the same edges touch:
		129
		130	mirror load "$HOME/mypic.png"
		131
		132	This is also a typical background expression:
		133
		134	rootalign root
		135
		136	It first takes a snapshot of the screen background image, and then
		137	moves it to the upper left corner of the screen - the result is
		138	pseudo-transparency, as the image seems to be static while the window is
		139	moved around.
		140
		141	=head2 CYCLES AND CACHING
		142
		143	As has been mentioned before, the expression might be evaluated multiple
		144	times. Each time the expression is reevaluated, a new cycle is said to
		145	have begun. Many operators cache their results till the next cycle.
		146
		147	For example, the C<load> operator keeps a copy of the image. If it is
		148	asked to load the same image on the next cycle it will not load it again,
		149	but return the cached copy.
		150
		151	This only works for one cycle though, so as long as you load the same
		152	image every time, it will always be cached, but when you load a different
		153	image, it will forget about the first one.
		154
		155	This allows you to either speed things up by keeping multiple images in
		156	memory, or comserve memory by loading images more often.
		157
		158	For example, you can keep two images in memory and use a random one like
		159	this:
		160
		161	my $img1 = load "img1.png";
		162	my $img2 = load "img2.png";
		163	(0.5 > rand) ? $img1 : $img2
		164
		165	Since both images are "loaded" every time the expression is evaluated,
		166	they are always kept in memory. Contrast this version:
		167
		168	my $path1 = "img1.png";
		169	my $path2 = "img2.png";
		170	load ((0.5 > rand) ? $path1 : $path2)
		171
		172	Here, a path is selected randomly, and load is only called for one image,
		173	so keeps only one image in memory. If, on the next evaluation, luck
		174	decides to use the other path, then it will have to load that image again.
		175
17	=head2 REFERENCE	176	=head1 REFERENCE
18		177
19	=cut	178	=head2 COMMAND LINE SWITCHES
20		179
21	our $EXPR;	180	=over 4
22	#$EXPR = 'move W * 0.1, -H * 0.1, resize W * 0.5, H * 0.5, repeat_none load "opensource.png"';
23	$EXPR = 'move -TX, -TY, load "argb.png"';
24	#$EXPR = '
25	# rotate W, H, 50, 50, counter 1/59.95, repeat_mirror,
26	# clip X, Y, W, H, repeat_mirror,
27	# load "/root/pix/das_fette_schwein.jpg"
28	#';
29	#$EXPR = 'solid "red"';
30	#$EXPR = 'blur root, 10, 10'
31	#$EXPR = 'blur move (root, -x, -y), 5, 5'
32	#resize load "/root/pix/das_fette_schwein.jpg", w, h
33		181
		182	=item --background-expr perl-expression
		183
		184	Specifies the Perl expression to evaluate.
		185
		186	=item --background-border
		187
		188	By default, the expression creates an image that fills the full window,
		189	overwriting borders and any other areas, such as the scrollbar.
		190
		191	Specifying this flag changes the behaviour, so that the image only
		192	replaces the background of the character area.
		193
		194	=back
		195
		196	=cut
		197
		198	our $HOME;
34	our ($self, $old, $new);	199	our ($self, $old, $new);
35	our ($x, $y, $w, $h);	200	our ($x, $y, $w, $h);
36		201
37	# enforce at least this interval between updates	202	# enforce at least this interval between updates
38	our $MIN_INTERVAL = 1/100;	203	our $MIN_INTERVAL = 1/100;
39		204
40	{	205	{
41	package urxvt::bgdsl; # background language	206	package urxvt::bgdsl; # background language
		207
		208	use List::Util qw(min max sum shuffle);
42		209
43	=head2 PROVIDERS/GENERATORS	210	=head2 PROVIDERS/GENERATORS
44		211
45	These functions provide an image, by loading it from disk, grabbing it	212	These functions provide an image, by loading it from disk, grabbing it
46	from the root screen or by simply generating it. They are used as starting	213	from the root screen or by simply generating it. They are used as starting
…		…
83	=item solid $width, $height, $colour	250	=item solid $width, $height, $colour
84		251
85	Creates a new image and completely fills it with the given colour. The	252	Creates a new image and completely fills it with the given colour. The
86	image is set to tiling mode.	253	image is set to tiling mode.
87		254
88	If <$width> and C<$height> are omitted, it creates a 1x1 image, which is	255	If C<$width> and C<$height> are omitted, it creates a 1x1 image, which is
89	useful for solid backgrounds or for use in filtering effects.	256	useful for solid backgrounds or for use in filtering effects.
90		257
91	=cut	258	=cut
92		259
93	sub solid($$;$) {	260	sub solid($;$$) {
94	my $colour = pop;	261	my $colour = pop;
95		262
96	my $img = $self->new_img (urxvt::PictStandardARGB32, $_[0] \|\| 1, $_[1] \|\| 1);	263	my $img = $self->new_img (urxvt::PictStandardARGB32, $_[0] \|\| 1, $_[1] \|\| 1);
97	$img->fill ($colour);	264	$img->fill ($colour);
98	$img	265	$img
99	}	266	}
100		267
		268	=item clone $img
		269
		270	Returns an exact copy of the image. This is useful if you want to have
		271	multiple copies of the same image to apply different effects to.
		272
		273	=cut
		274
		275	sub clone($) {
		276	$_[0]->clone
		277	}
		278
101	=back	279	=back
102		280
		281	=head2 TILING MODES
		282
		283	The following operators modify the tiling mode of an image, that is, the
		284	way that pixels outside the image area are painted when the image is used.
		285
		286	=over 4
		287
		288	=item tile $img
		289
		290	Tiles the whole plane with the image and returns this new image - or in
		291	other words, it returns a copy of the image in plane tiling mode.
		292
		293	Example: load an image and tile it over the background, without
		294	resizing. The C<tile> call is superfluous because C<load> already defaults
		295	to tiling mode.
		296
		297	tile load "mybg.png"
		298
		299	=item mirror $img
		300
		301	Similar to tile, but reflects the image each time it uses a new copy, so
		302	that top edges always touch top edges, right edges always touch right
		303	edges and so on (with normal tiling, left edges always touch right edges
		304	and top always touch bottom edges).
		305
		306	Example: load an image and mirror it over the background, avoiding sharp
		307	edges at the image borders at the expense of mirroring the image itself
		308
		309	mirror load "mybg.png"
		310
		311	=item pad $img
		312
		313	Takes an image and modifies it so that all pixels outside the image area
		314	become transparent. This mode is most useful when you want to place an
		315	image over another image or the background colour while leaving all
		316	background pixels outside the image unchanged.
		317
		318	Example: load an image and display it in the upper left corner. The rest
		319	of the space is left "empty" (transparent or wahtever your compisotr does
		320	in alpha mode, else background colour).
		321
		322	pad load "mybg.png"
		323
		324	=item extend $img
		325
		326	Extends the image over the whole plane, using the closest pixel in the
		327	area outside the image. This mode is mostly useful when you more complex
		328	filtering operations and want the pixels outside the image to have the
		329	same values as the pixels near the edge.
		330
		331	Example: just for curiosity, how does this pixel extension stuff work?
		332
		333	extend move 50, 50, load "mybg.png"
		334
		335	=cut
		336
		337	sub pad($) {
		338	my $img = $_[0]->clone;
		339	$img->repeat_mode (urxvt::RepeatNone);
		340	$img
		341	}
		342
		343	sub tile($) {
		344	my $img = $_[0]->clone;
		345	$img->repeat_mode (urxvt::RepeatNormal);
		346	$img
		347	}
		348
		349	sub mirror($) {
		350	my $img = $_[0]->clone;
		351	$img->repeat_mode (urxvt::RepeatReflect);
		352	$img
		353	}
		354
		355	sub extend($) {
		356	my $img = $_[0]->clone;
		357	$img->repeat_mode (urxvt::RepeatPad);
		358	$img
		359	}
		360
		361	=back
		362
103	=head2 VARIABLES	363	=head2 VARIABLE VALUES
104		364
105	The following functions provide variable data such as the terminal	365	The following functions provide variable data such as the terminal window
		366	dimensions. They are not (Perl-) variables, they just return stuff that
106	window dimensions. Most of them make your expression sensitive to some	367	varies. Most of them make your expression sensitive to some events, for
107	events, for example using C<TW> (terminal width) means your expression is	368	example using C<TW> (terminal width) means your expression is evaluated
108	evaluated again when the terminal is resized.	369	again when the terminal is resized.
109		370
110	=over 4	371	=over 4
111		372
112	=item TX	373	=item TX
113		374
…		…
160		421
161	When this function is used the expression will be reevaluated again in	422	When this function is used the expression will be reevaluated again in
162	C<$seconds> seconds.	423	C<$seconds> seconds.
163		424
164	Example: load some image and rotate it according to the time of day (as if it were	425	Example: load some image and rotate it according to the time of day (as if it were
165	the hour pointer of a clock). update this image every minute.	426	the hour pointer of a clock). Update this image every minute.
166		427
167	again 60; rotate TW, TH, 50, 50, (now % 86400) * -720 / 86400, scale load "myclock.png"	428	again 60; rotate TW, TH, 50, 50, (now % 86400) * -720 / 86400, scale load "myclock.png"
168		429
169	=item counter $seconds	430	=item counter $seconds
170		431
…		…
184	$self->{counter} + 0	445	$self->{counter} + 0
185	}	446	}
186		447
187	=back	448	=back
188		449
189	=head2 TILING MODES	450	=head2 SHAPE CHANGING OPERATORS
190		451
191	The following operators modify the tiling mode of an image, that is, the	452	The following operators modify the shape, size or position of the image.
192	way that pixels outside the image area are painted when the image is used.
193		453
194	=over 4	454	=over 4
195
196	=item tile $img
197
198	Tiles the whole plane with the image and returns this new image - or in
199	other words, it returns a copy of the image in plane tiling mode.
200
201	Example: load an image and tile it over the background, without
202	resizing. The C<tile> call is superfluous because C<load> already defaults
203	to tiling mode.
204
205	tile load "mybg.png"
206
207	=item mirror $img
208
209	Similar to tile, but reflects the image each time it uses a new copy, so
210	that top edges always touch top edges, right edges always touch right
211	edges and so on (with normal tiling, left edges always touch right edges
212	and top always touch bottom edges).
213
214	Exmaple: load an image and mirror it over the background, avoiding sharp
215	edges at the image borders at the expense of mirroring the image itself
216
217	mirror load "mybg.png"
218
219	=item pad $img
220
221	Takes an image and modifies it so that all pixels outside the image area
222	become transparent. This mode is most useful when you want to place an
223	image over another image or the background colour while leaving all
224	background pixels outside the image unchanged.
225
226	Example: load an image and display it in the upper left corner. The rets
227	of the space is left "empty" (transparent or wahtever your compisotr does
228	in alpha mode, else background colour).
229
230	pad load "mybg.png"
231
232	=item extend $img
233
234	Extends the image over the whole plane, using the closest pixel in the
235	area outside the image. This mode is mostly useful when you more complex
236	filtering operations and want the pixels outside the image to have the
237	same values as the pixels near the edge.
238
239	Example: just for curiosity, how does this pixel extension stuff work?
240
241	extend move 50, 50, load "mybg.png"
242
243	=cut
244
245	sub pad($) {
246	my $img = $_[0]->clone;
247	$img->repeat_mode (urxvt::RepeatNone);
248	$img
249	}
250
251	sub tile($) {
252	my $img = $_[0]->clone;
253	$img->repeat_mode (urxvt::RepeatNormal);
254	$img
255	}
256
257	sub mirror($) {
258	my $img = $_[0]->clone;
259	$img->repeat_mode (urxvt::RepeatReflect);
260	$img
261	}
262
263	sub extend($) {
264	my $img = $_[0]->clone;
265	$img->repeat_mode (urxvt::RepeatPad);
266	$img
267	}
268
269	=back
270
271	=head2 PIXEL OPERATORS
272
273	The following operators modify the image pixels in various ways.
274
275	=over 4
276
277	=item clone $img
278
279	Returns an exact copy of the image.
280
281	=cut
282
283	sub clone($) {
284	$_[0]->clone
285	}
286		455
287	=item clip $img	456	=item clip $img
288		457
289	=item clip $width, $height, $img	458	=item clip $width, $height, $img
290		459
…		…
314	$img->sub_rect ($_[0], $_[1], $w, $h)	483	$img->sub_rect ($_[0], $_[1], $w, $h)
315	}	484	}
316		485
317	=item scale $img	486	=item scale $img
318		487
319	=item scale $size_percent, $img	488	=item scale $size_factor, $img
320		489
321	=item scale $width_percent, $height_percent, $img	490	=item scale $width_factor, $height_factor, $img
322		491
323	Scales the image by the given percentages in horizontal	492	Scales the image by the given factors in horizontal
324	(C<$width_percent>) and vertical (C<$height_percent>) direction.	493	(C<$width>) and vertical (C<$height>) direction.
325		494
326	If only one percentage is give, it is used for both directions.	495	If only one factor is give, it is used for both directions.
327		496
328	If no percentages are given, scales the image to the window size without	497	If no factors are given, scales the image to the window size without
329	keeping aspect.	498	keeping aspect.
330		499
331	=item resize $width, $height, $img	500	=item resize $width, $height, $img
332		501
333	Resizes the image to exactly C<$width> times C<$height> pixels.	502	Resizes the image to exactly C<$width> times C<$height> pixels.
334		503
335	=cut	504	=item fit $img
336		505
337	#TODO: maximise, maximise_fill?	506	=item fit $width, $height, $img
		507
		508	Fits the image into the given C<$width> and C<$height> without changing
		509	aspect, or the terminal size. That means it will be shrunk or grown until
		510	the whole image fits into the given area, possibly leaving borders.
		511
		512	=item cover $img
		513
		514	=item cover $width, $height, $img
		515
		516	Similar to C<fit>, but shrinks or grows until all of the area is covered
		517	by the image, so instead of potentially leaving borders, it will cut off
		518	image data that doesn't fit.
		519
		520	=cut
338		521
339	sub scale($;$;$) {	522	sub scale($;$;$) {
340	my $img = pop;	523	my $img = pop;
341		524
342	@_ == 2 ? $img->scale ($_[0] * $img->w * 0.01, $_[1] * $img->h * 0.01)	525	@_ == 2 ? $img->scale ($_[0] * $img->w, $_[1] * $img->h)
343	: @_ ? $img->scale ($_[0] * $img->w * 0.01, $_[0] * $img->h * 0.01)	526	: @_ ? $img->scale ($_[0] * $img->w, $_[0] * $img->h)
344	: $img->scale (TW, TH)	527	: $img->scale (TW, TH)
345	}	528	}
346		529
347	sub resize($$$) {	530	sub resize($$$) {
348	my $img = pop;	531	my $img = pop;
349	$img->scale ($_[0], $_[1])	532	$img->scale ($_[0], $_[1])
350	}	533	}
		534
		535	sub fit($;$$) {
		536	my $img = pop;
		537	my $w = ($_[0] \|\| TW) / $img->w;
		538	my $h = ($_[1] \|\| TH) / $img->h;
		539	scale +(min $w, $h), $img
		540	}
		541
		542	sub cover($;$$) {
		543	my $img = pop;
		544	my $w = ($_[0] \|\| TW) / $img->w;
		545	my $h = ($_[1] \|\| TH) / $img->h;
		546	scale +(max $w, $h), $img
		547	}
		548
		549	=item move $dx, $dy, $img
		550
		551	Moves the image by C<$dx> pixels in the horizontal, and C<$dy> pixels in
		552	the vertical.
		553
		554	Example: move the image right by 20 pixels and down by 30.
		555
		556	move 20, 30, ...
		557
		558	=item center $img
		559
		560	=item center $width, $height, $img
		561
		562	Centers the image, i.e. the center of the image is moved to the center of
		563	the terminal window (or the box specified by C<$width> and C<$height> if
		564	given).
		565
		566	=item rootalign $img
		567
		568	Moves the image so that it appears glued to the screen as opposed to the
		569	window. This gives the illusion of a larger area behind the window. It is
		570	exactly equivalent to C<move -TX, -TY>, that is, it moves the image to the
		571	top left of the screen.
		572
		573	Example: load a background image, put it in mirror mode and root align it.
		574
		575	rootalign mirror load "mybg.png"
		576
		577	Example: take the screen background and align it, giving the illusion of
		578	transparency as long as the window isn't in front of other windows.
		579
		580	rootalign root
		581
		582	=cut
351		583
352	sub move($$;$) {	584	sub move($$;$) {
353	my $img = pop->clone;	585	my $img = pop->clone;
354	$img->move ($_[0], $_[1]);	586	$img->move ($_[0], $_[1]);
355	$img	587	$img
356	}	588	}
357		589
		590	sub center($;$$) {
		591	my $img = pop;
		592	my $w = $_[0] \|\| TW;
		593	my $h = $_[0] \|\| TH;
		594
		595	move 0.5 * ($w - $img->w), 0.5 * ($h - $img->h), $img
		596	}
		597
		598	sub rootalign($) {
		599	move -TX, -TY, $_[0]
		600	}
		601
		602	=back
		603
		604	=head2 COLOUR MODIFICATIONS
		605
		606	The following operators change the pixels of the image.
		607
		608	=over 4
		609
		610	=item contrast $factor, $img
		611
		612	=item contrast $r, $g, $b, $img
		613
		614	=item contrast $r, $g, $b, $a, $img
		615
		616	Adjusts the I<contrast> of an image.
		617
		618	The first form applies a single C<$factor> to red, green and blue, the
		619	second form applies separate factors to each colour channel, and the last
		620	form includes the alpha channel.
		621
		622	Values from 0 to 1 lower the contrast, values higher than 1 increase the
		623	contrast.
		624
		625	Due to limitations in the underlying XRender extension, lowering contrast
		626	also reduces brightness, while increasing contrast currently also
		627	increases brightness.
		628
		629	=item brightness $bias, $img
		630
		631	=item brightness $r, $g, $b, $img
		632
		633	=item brightness $r, $g, $b, $a, $img
		634
		635	Adjusts the brightness of an image.
		636
		637	The first form applies a single C<$bias> to red, green and blue, the
		638	second form applies separate biases to each colour channel, and the last
		639	form includes the alpha channel.
		640
		641	Values less than 0 reduce brightness, while values larger than 0 increase
		642	it. Useful range is from -1 to 1 - the former results in a black, the
		643	latter in a white picture.
		644
		645	Due to idiosynchrasies in the underlying XRender extension, biases less
		646	than zero can be I<very> slow.
		647
		648	=cut
		649
		650	sub contrast($$;$$;$) {
		651	my $img = pop;
		652	my ($r, $g, $b, $a) = @_;
		653
		654	($g, $b) = ($r, $r) if @_ < 4;
		655	$a = 1 if @_ < 5;
		656
		657	$img = $img->clone;
		658	$img->contrast ($r, $g, $b, $a);
		659	$img
		660	}
		661
		662	sub brightness($$;$$;$) {
		663	my $img = pop;
		664	my ($r, $g, $b, $a) = @_;
		665
		666	($g, $b) = ($r, $r) if @_ < 4;
		667	$a = 1 if @_ < 5;
		668
		669	$img = $img->clone;
		670	$img->brightness ($r, $g, $b, $a);
		671	$img
		672	}
		673
		674	=item blur $radius, $img
		675
		676	=item blur $radius_horz, $radius_vert, $img
		677
		678	Gaussian-blurs the image with (roughly) C<$radius> pixel radius. The radii
		679	can also be specified separately.
		680
		681	Blurring is often I<very> slow, at least compared or other
		682	operators. Larger blur radii are slower than smaller ones, too, so if you
		683	don't want to freeze your screen for long times, start experimenting with
		684	low values for radius (<5).
		685
		686	=cut
		687
		688	sub blur($$;$) {
		689	my $img = pop;
		690	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])
		691	}
		692
		693	=item rotate $new_width, $new_height, $center_x, $center_y, $degrees
		694
		695	Rotates the image by C<$degrees> degrees, counter-clockwise, around the
		696	pointer at C<$center_x> and C<$center_y> (specified as factor of image
		697	width/height), generating a new image with width C<$new_width> and height
		698	C<$new_height>.
		699
		700	#TODO# new width, height, maybe more operators?
		701
		702	Example: rotate the image by 90 degrees
		703
		704	=cut
		705
358	sub rotate($$$$$$) {	706	sub rotate($$$$$$) {
359	my $img = pop;	707	my $img = pop;
360	$img->rotate (	708	$img->rotate (
361	$_[0],	709	$_[0],
362	$_[1],	710	$_[1],
363	$_[2] * $img->w * .01,	711	$_[2] * $img->w,
364	$_[3] * $img->h * .01,	712	$_[3] * $img->h,
365	$_[4] * (3.14159265 / 180),	713	$_[4] * (3.14159265 / 180),
366	)	714	)
367	}
368
369	sub blur($$;$) {
370	my $img = pop;
371	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])
372	}
373
374	sub contrast($$;$$;$) {
375	my $img = pop;
376	my ($r, $g, $b, $a) = @_;
377
378	($g, $b) = ($r, $r) if @_ < 4;
379	$a = 1 if @_ < 5;
380
381	$img = $img->clone;
382	$img->contrast ($r, $g, $b, $a);
383	$img
384	}
385
386	sub brightness($$;$$;$) {
387	my $img = pop;
388	my ($r, $g, $b, $a) = @_;
389
390	($g, $b) = ($r, $r) if @_ < 4;
391	$a = 1 if @_ < 5;
392
393	$img = $img->clone;
394	$img->brightness ($r, $g, $b, $a);
395	$img
396	}	715	}
397		716
398	=back	717	=back
399		718
400	=cut	719	=cut
…		…
432		751
433	# set environment to evaluate user expression	752	# set environment to evaluate user expression
434		753
435	local $self = $arg_self;	754	local $self = $arg_self;
436		755
		756	local $HOME = $ENV{HOME};
437	local $old = $self->{state};	757	local $old = $self->{state};
438	local $new = my $state = $self->{state} = {};	758	local $new = my $state = $self->{state} = {};
439		759
440	($x, $y, $w, $h) =	760	($x, $y, $w, $h) =
441	$self->background_geometry ($self->{border});	761	$self->background_geometry ($self->{border});

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Comparing rxvt-unicode/src/perl/background (file contents): Revision 1.35 by root, Fri Jun 8 08:06:38 2012 UTC vs. Revision 1.45 by root, Sun Jun 10 11:53:32 2012 UTC

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Comparing rxvt-unicode/src/perl/background (file contents):
Revision 1.35 by root, Fri Jun 8 08:06:38 2012 UTC vs.
Revision 1.45 by root, Sun Jun 10 11:53:32 2012 UTC