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

Comparing rxvt-unicode/src/perl/background (file contents):
Revision 1.49 by root, Sun Jun 10 15:29:18 2012 UTC vs.
Revision 1.54 by root, Thu Jun 14 16:22:20 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	#:META:X_RESOURCE:%.interval:seconds:minimum time between updates	5	#:META:X_RESOURCE:%.interval:seconds:minimum time between updates
6
7	#TODO: once, rootalign
8		6
9	=head1 NAME	7	=head1 NAME
10		8
11	background - manage terminal background	9	background - manage terminal background
12		10
59		57
60	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
61	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
62	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
63	example. That ensures that the picture always fills the terminal, even	61	example. That ensures that the picture always fills the terminal, even
64	after it's size changes.	62	after its size changes.
65		63
66	=head2 EXPRESSIONS	64	=head2 EXPRESSIONS
67		65
68	Expressions are normal Perl expressions, in fact, they are Perl blocks -	66	Expressions are normal Perl expressions, in fact, they are Perl blocks -
69	which means you could use multiple lines and statements:	67	which means you could use multiple lines and statements:
…		…
73	return scale load "$HOME/weekday.png";	71	return scale load "$HOME/weekday.png";
74	} else {	72	} else {
75	return scale load "$HOME/sunday.png";	73	return scale load "$HOME/sunday.png";
76	}	74	}
77		75
78	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
79	background on Sundays, and F<weekday.png> on all other days.	77	background on Sundays, and F<weekday.png> on all other days.
80		78
81	Fortunately, we expect that most expressions will be much simpler, with	79	Fortunately, we expect that most expressions will be much simpler, with
82	little Perl knowledge needed.	80	little Perl knowledge needed.
83		81
…		…
117	horizontal and vertical dimensions. For example, this halves the image	115	horizontal and vertical dimensions. For example, this halves the image
118	width and doubles the image height:	116	width and doubles the image height:
119		117
120	scale 0.5, 2, load "$HOME/mypic.png"	118	scale 0.5, 2, load "$HOME/mypic.png"
121		119
122	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
123	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:
124		122
125	tile load "$HOME/mypic.png"	123	tile load "$HOME/mypic.png"
126		124
127	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
…		…
153	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
154	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
155	image, it will forget about the first one.	153	image, it will forget about the first one.
156		154
157	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
158	memory, or comserve memory by loading images more often.	156	memory, or conserve memory by loading images more often.
159		157
160	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
161	this:	159	this:
162		160
163	my $img1 = load "img1.png";	161	my $img1 = load "img1.png";
…		…
193	Specifying this flag changes the behaviour, so that the image only	191	Specifying this flag changes the behaviour, so that the image only
194	replaces the background of the character area.	192	replaces the background of the character area.
195		193
196	=item --background-interval seconds	194	=item --background-interval seconds
197		195
198	Since some operations in the underlying XRender extension can effetively	196	Since some operations in the underlying XRender extension can effectively
199	freeze your X-server for prolonged time, this extension enforces a minimum	197	freeze your X-server for prolonged time, this extension enforces a minimum
200	time between updates, which is normally about 0.1 seconds.	198	time between updates, which is normally about 0.1 seconds.
201		199
202	If you want to do updates more often, you can decrease this safety	200	If you want to do updates more often, you can decrease this safety
203	interval with this switch.	201	interval with this switch.
204		202
205	=back	203	=back
206		204
207	=cut	205	=cut
208		206
209	our %_IMGCACHE;	207	our %_IMG_CACHE;
		208	our %_ONCE_CACHE;
210	our $HOME;	209	our $HOME;
211	our ($self, $old, $new);	210	our ($self, $old, $new);
212	our ($x, $y, $w, $h);	211	our ($x, $y, $w, $h);
213		212
214	# enforce at least this interval between updates	213	# enforce at least this interval between updates
…		…
230	=item load $path	229	=item load $path
231		230
232	Loads the image at the given C<$path>. The image is set to plane tiling	231	Loads the image at the given C<$path>. The image is set to plane tiling
233	mode.	232	mode.
234		233
235	Loaded images will be cached for one cycle.	234	Loaded images will be cached for one cycle, and shared between temrinals
		235	running in the same process (e.g. in C<urxvtd>).
236		236
		237	=item load_uc $path
		238
		239	Load uncached - same as load, but does not cache the image. This function
		240	is most useufl if you want to optimise a background expression in some
		241	way.
		242
237	=cut	243	=cut
		244
		245	sub load_uc($) {
		246	my ($path) = @_;
		247
		248	$_IMG_CACHE{$path} \|\| do {
		249	my $img = $self->new_img_from_file ($path);
		250	Scalar::Util::weaken ($_IMG_CACHE{$path} = $img);
		251	$img
		252	}
		253	}
238		254
239	sub load($) {	255	sub load($) {
240	my ($path) = @_;	256	my ($path) = @_;
241		257
242	$new->{load}{$path} = $old->{load}{$path} \|\| $self->new_img_from_file ($path);	258	$new->{load}{$path} = $old->{load}{$path} \|\| load_uc $path;
243	}	259	}
244		260
245	=item root	261	=item root
246		262
247	Returns the root window pixmap, that is, hopefully, the background image	263	Returns the root window pixmap, that is, hopefully, the background image
…		…
252		268
253	=cut	269	=cut
254		270
255	sub root() {	271	sub root() {
256	$new->{rootpmap_sensitive} = 1;	272	$new->{rootpmap_sensitive} = 1;
257	die "root op not supported, exg, we need you";	273	$self->new_img_from_root
258	}	274	}
259		275
260	=item solid $colour	276	=item solid $colour
261		277
262	=item solid $width, $height, $colour	278	=item solid $width, $height, $colour
…		…
285	=cut	301	=cut
286		302
287	sub clone($) {	303	sub clone($) {
288	$_[0]->clone	304	$_[0]->clone
289	}	305	}
290
291	=back
292		306
293	=head2 TILING MODES	307	=head2 TILING MODES
294		308
295	The following operators modify the tiling mode of an image, that is, the	309	The following operators modify the tiling mode of an image, that is, the
296	way that pixels outside the image area are painted when the image is used.	310	way that pixels outside the image area are painted when the image is used.
…		…
326	become transparent. This mode is most useful when you want to place an	340	become transparent. This mode is most useful when you want to place an
327	image over another image or the background colour while leaving all	341	image over another image or the background colour while leaving all
328	background pixels outside the image unchanged.	342	background pixels outside the image unchanged.
329		343
330	Example: load an image and display it in the upper left corner. The rest	344	Example: load an image and display it in the upper left corner. The rest
331	of the space is left "empty" (transparent or wahtever your compisotr does	345	of the space is left "empty" (transparent or whatever your compositor does
332	in alpha mode, else background colour).	346	in alpha mode, else background colour).
333		347
334	pad load "mybg.png"	348	pad load "mybg.png"
335		349
336	=item extend $img	350	=item extend $img
337		351
338	Extends the image over the whole plane, using the closest pixel in the	352	Extends the image over the whole plane, using the closest pixel in the
339	area outside the image. This mode is mostly useful when you more complex	353	area outside the image. This mode is mostly useful when you use more complex
340	filtering operations and want the pixels outside the image to have the	354	filtering operations and want the pixels outside the image to have the
341	same values as the pixels near the edge.	355	same values as the pixels near the edge.
342		356
343	Example: just for curiosity, how does this pixel extension stuff work?	357	Example: just for curiosity, how does this pixel extension stuff work?
344		358
…		…
435	C<$seconds> seconds.	449	C<$seconds> seconds.
436		450
437	Example: load some image and rotate it according to the time of day (as if it were	451	Example: load some image and rotate it according to the time of day (as if it were
438	the hour pointer of a clock). Update this image every minute.	452	the hour pointer of a clock). Update this image every minute.
439		453
440	again 60; rotate TW, TH, 50, 50, (now % 86400) * -720 / 86400, scale load "myclock.png"	454	again 60; rotate 50, 50, (now % 86400) * -720 / 86400, scale load "myclock.png"
441		455
442	=item counter $seconds	456	=item counter $seconds
443		457
444	Like C<again>, but also returns an increasing counter value, starting at	458	Like C<again>, but also returns an increasing counter value, starting at
445	0, which might be useful for some simple animation effects.	459	0, which might be useful for some simple animation effects.
…		…
632		646
633	sub rootalign($) {	647	sub rootalign($) {
634	move -TX, -TY, $_[0]	648	move -TX, -TY, $_[0]
635	}	649	}
636		650
		651	=item rotate $center_x, $center_y, $degrees
		652
		653	Rotates the image by C<$degrees> degrees, counter-clockwise, around the
		654	pointer at C<$center_x> and C<$center_y> (specified as factor of image
		655	width/height).
		656
		657	#TODO# new width, height, maybe more operators?
		658
		659	Example: rotate the image by 90 degrees
		660
		661	=cut
		662
		663	sub rotate($$$$) {
		664	my $img = pop;
		665	$img->rotate (
		666	$_[0] * $img->w,
		667	$_[1] * $img->h,
		668	$_[2] * (3.14159265 / 180),
		669	)
		670	}
		671
637	=back	672	=back
638		673
639	=head2 COLOUR MODIFICATIONS	674	=head2 COLOUR MODIFICATIONS
640		675
641	The following operators change the pixels of the image.	676	The following operators change the pixels of the image.
…		…
675		710
676	Values less than 0 reduce brightness, while values larger than 0 increase	711	Values less than 0 reduce brightness, while values larger than 0 increase
677	it. Useful range is from -1 to 1 - the former results in a black, the	712	it. Useful range is from -1 to 1 - the former results in a black, the
678	latter in a white picture.	713	latter in a white picture.
679		714
680	Due to idiosynchrasies in the underlying XRender extension, biases less	715	Due to idiosyncrasies in the underlying XRender extension, biases less
681	than zero can be I<very> slow.	716	than zero can be I<very> slow.
682		717
683	=cut	718	=cut
684		719
685	sub contrast($$;$$;$) {	720	sub contrast($$;$$;$) {
…		…
723	sub blur($$;$) {	758	sub blur($$;$) {
724	my $img = pop;	759	my $img = pop;
725	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])	760	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])
726	}	761	}
727		762
728	=item rotate $new_width, $new_height, $center_x, $center_y, $degrees	763	=back
729		764
730	Rotates the image by C<$degrees> degrees, counter-clockwise, around the	765	=head2 OTHER STUFF
731	pointer at C<$center_x> and C<$center_y> (specified as factor of image
732	width/height), generating a new image with width C<$new_width> and height
733	C<$new_height>.
734		766
735	#TODO# new width, height, maybe more operators?	767	Anything that didn't fit any of the other categories, even after appliyng
		768	force and closing our eyes.
736		769
737	Example: rotate the image by 90 degrees	770	=over 4
738		771
739	=cut	772	=item once { ... }
740		773
741	sub rotate($$$$$$) {	774	This function takes a code block as argument, that is, one or more
742	my $img = pop;	775	statements enclosed by braces.
743	$img->rotate (	776
744	$_[0],	777	The trick is that this code block is only evaluated once - future calls
745	$_[1],	778	will simply return the original image (yes, it should only be used with
746	$_[2] * $img->w,	779	images).
747	$_[3] * $img->h,	780
748	$_[4] * (3.14159265 / 180),	781	This can be extremely useful to avoid redoign the same slow operations
749	)	782	again and again- for example, if your background expression takes the root
		783	background, blurs it and then root-aligns it it would have to blur the
		784	root background on every window move or resize.
		785
		786	Putting the blur into a C<once> block will make sure the blur is only done
		787	once:
		788
		789	rootlign once { blur 10, root }
		790
		791	This leaves the question of how to force reevaluation of the block, in
		792	case the root background changes: Right now, all once blocks forget that
		793	they ahve been executed before each time the root background changes (if
		794	the expression is sensitive to that) or when C<once_again> is called.
		795
		796	=item once_again
		797
		798	Resets all C<once> block as if they had never been called, i.e. on the
		799	next call they will be reevaluated again.
		800
		801	=cut
		802
		803	sub once(&) {
		804	$_ONCE_CACHE{$_[0]+0} \|\|= $_[0]()
		805	}
		806
		807	sub once_again() {
		808	%_ONCE_CACHE = ();
750	}	809	}
751		810
752	=back	811	=back
753		812
754	=cut	813	=cut

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Comparing rxvt-unicode/src/perl/background (file contents): Revision 1.49 by root, Sun Jun 10 15:29:18 2012 UTC vs. Revision 1.54 by root, Thu Jun 14 16:22:20 2012 UTC

Diff Legend

Comparing rxvt-unicode/src/perl/background (file contents):
Revision 1.49 by root, Sun Jun 10 15:29:18 2012 UTC vs.
Revision 1.54 by root, Thu Jun 14 16:22:20 2012 UTC