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

Comparing rxvt-unicode/src/perl/background (file contents):
Revision 1.46 by root, Sun Jun 10 13:32:55 2012 UTC vs.
Revision 1.52 by root, Tue Jun 12 10:45:53 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:
…		…
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
		207	our %_IMG_CACHE;
		208	our %_ONCE_CACHE;
209	our $HOME;	209	our $HOME;
210	our ($self, $old, $new);	210	our ($self, $old, $new);
211	our ($x, $y, $w, $h);	211	our ($x, $y, $w, $h);
212		212
213	# enforce at least this interval between updates	213	# enforce at least this interval between updates
…		…
251		251
252	=cut	252	=cut
253		253
254	sub root() {	254	sub root() {
255	$new->{rootpmap_sensitive} = 1;	255	$new->{rootpmap_sensitive} = 1;
256	die "root op not supported, exg, we need you";	256	$self->new_img_from_root
257	}	257	}
258		258
259	=item solid $colour	259	=item solid $colour
260		260
261	=item solid $width, $height, $colour	261	=item solid $width, $height, $colour
…		…
284	=cut	284	=cut
285		285
286	sub clone($) {	286	sub clone($) {
287	$_[0]->clone	287	$_[0]->clone
288	}	288	}
289
290	=back
291		289
292	=head2 TILING MODES	290	=head2 TILING MODES
293		291
294	The following operators modify the tiling mode of an image, that is, the	292	The following operators modify the tiling mode of an image, that is, the
295	way that pixels outside the image area are painted when the image is used.	293	way that pixels outside the image area are painted when the image is used.
…		…
325	become transparent. This mode is most useful when you want to place an	323	become transparent. This mode is most useful when you want to place an
326	image over another image or the background colour while leaving all	324	image over another image or the background colour while leaving all
327	background pixels outside the image unchanged.	325	background pixels outside the image unchanged.
328		326
329	Example: load an image and display it in the upper left corner. The rest	327	Example: load an image and display it in the upper left corner. The rest
330	of the space is left "empty" (transparent or wahtever your compisotr does	328	of the space is left "empty" (transparent or whatever your compositor does
331	in alpha mode, else background colour).	329	in alpha mode, else background colour).
332		330
333	pad load "mybg.png"	331	pad load "mybg.png"
334		332
335	=item extend $img	333	=item extend $img
336		334
337	Extends the image over the whole plane, using the closest pixel in the	335	Extends the image over the whole plane, using the closest pixel in the
338	area outside the image. This mode is mostly useful when you more complex	336	area outside the image. This mode is mostly useful when you use more complex
339	filtering operations and want the pixels outside the image to have the	337	filtering operations and want the pixels outside the image to have the
340	same values as the pixels near the edge.	338	same values as the pixels near the edge.
341		339
342	Example: just for curiosity, how does this pixel extension stuff work?	340	Example: just for curiosity, how does this pixel extension stuff work?
343		341
…		…
631		629
632	sub rootalign($) {	630	sub rootalign($) {
633	move -TX, -TY, $_[0]	631	move -TX, -TY, $_[0]
634	}	632	}
635		633
		634	=item rotate $center_x, $center_y, $degrees, $new_width, $new_height
		635
		636	Rotates the image by C<$degrees> degrees, counter-clockwise, around the
		637	pointer at C<$center_x> and C<$center_y> (specified as factor of image
		638	width/height), generating a new image with width C<$new_width> and height
		639	C<$new_height>.
		640
		641	#TODO# new width, height, maybe more operators?
		642
		643	Example: rotate the image by 90 degrees
		644
		645	=cut
		646
		647	sub rotate($$$$$$) {
		648	my $img = pop;
		649	$img->rotate (
		650	$_[0] * $img->w,
		651	$_[1] * $img->h,
		652	$_[2] * (3.14159265 / 180),
		653	$_[3],
		654	$_[4],
		655	)
		656	}
		657
636	=back	658	=back
637		659
638	=head2 COLOUR MODIFICATIONS	660	=head2 COLOUR MODIFICATIONS
639		661
640	The following operators change the pixels of the image.	662	The following operators change the pixels of the image.
…		…
674		696
675	Values less than 0 reduce brightness, while values larger than 0 increase	697	Values less than 0 reduce brightness, while values larger than 0 increase
676	it. Useful range is from -1 to 1 - the former results in a black, the	698	it. Useful range is from -1 to 1 - the former results in a black, the
677	latter in a white picture.	699	latter in a white picture.
678		700
679	Due to idiosynchrasies in the underlying XRender extension, biases less	701	Due to idiosyncrasies in the underlying XRender extension, biases less
680	than zero can be I<very> slow.	702	than zero can be I<very> slow.
681		703
682	=cut	704	=cut
683		705
684	sub contrast($$;$$;$) {	706	sub contrast($$;$$;$) {
685	my $img = pop;	707	my $img = pop;
686	my ($r, $g, $b, $a) = @_;	708	my ($r, $g, $b, $a) = @_;
687		709
688	($g, $b) = ($r, $r) if @_ < 4;	710	($g, $b) = ($r, $r) if @_ < 3;
689	$a = 1 if @_ < 5;	711	$a = 1 if @_ < 4;
690		712
691	$img = $img->clone;	713	$img = $img->clone;
692	$img->contrast ($r, $g, $b, $a);	714	$img->contrast ($r, $g, $b, $a);
693	$img	715	$img
694	}	716	}
695		717
696	sub brightness($$;$$;$) {	718	sub brightness($$;$$;$) {
697	my $img = pop;	719	my $img = pop;
698	my ($r, $g, $b, $a) = @_;	720	my ($r, $g, $b, $a) = @_;
699		721
700	($g, $b) = ($r, $r) if @_ < 4;	722	($g, $b) = ($r, $r) if @_ < 3;
701	$a = 1 if @_ < 5;	723	$a = 1 if @_ < 4;
702		724
703	$img = $img->clone;	725	$img = $img->clone;
704	$img->brightness ($r, $g, $b, $a);	726	$img->brightness ($r, $g, $b, $a);
705	$img	727	$img
706	}	728	}
…		…
722	sub blur($$;$) {	744	sub blur($$;$) {
723	my $img = pop;	745	my $img = pop;
724	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])	746	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])
725	}	747	}
726		748
727	=item rotate $new_width, $new_height, $center_x, $center_y, $degrees	749	=back
728		750
729	Rotates the image by C<$degrees> degrees, counter-clockwise, around the	751	=head2 OTHER STUFF
730	pointer at C<$center_x> and C<$center_y> (specified as factor of image
731	width/height), generating a new image with width C<$new_width> and height
732	C<$new_height>.
733		752
734	#TODO# new width, height, maybe more operators?	753	Anything that didn't fit any of the other categories, even after appliyng
		754	force and closing our eyes.
735		755
736	Example: rotate the image by 90 degrees	756	=over 4
737		757
738	=cut	758	=item once { ... }
739		759
740	sub rotate($$$$$$) {	760	This function takes a code block as argument, that is, one or more
741	my $img = pop;	761	statements enclosed by braces.
742	$img->rotate (	762
743	$_[0],	763	The trick is that this code block is only evaluated once - future calls
744	$_[1],	764	will simply return the original image (yes, it should only be used with
745	$_[2] * $img->w,	765	images).
746	$_[3] * $img->h,	766
747	$_[4] * (3.14159265 / 180),	767	This can be extremely useful to avoid redoign the same slow operations
748	)	768	again and again- for example, if your background expression takes the root
		769	background, blurs it and then root-aligns it it would have to blur the
		770	root background on every window move or resize.
		771
		772	Putting the blur into a C<once> block will make sure the blur is only done
		773	once:
		774
		775	rootlign once { blur 10, root }
		776
		777	This leaves the question of how to force reevaluation of the block, in
		778	case the root background changes: Right now, all once blocks forget that
		779	they ahve been executed before each time the root background changes (if
		780	the expression is sensitive to that) or when C<once_again> is called.
		781
		782	=item once_again
		783
		784	Resets all C<once> block as if they had never been called, i.e. on the
		785	next call they will be reevaluated again.
		786
		787	=cut
		788
		789	sub once(&) {
		790	$_ONCE_CACHE{$_[0]+0} \|\|= $_[0]()
		791	}
		792
		793	sub once_again() {
		794	%_ONCE_CACHE = ();
749	}	795	}
750		796
751	=back	797	=back
752		798
753	=cut	799	=cut
…		…
796		842
797	# evaluate user expression	843	# evaluate user expression
798		844
799	my $img = eval { $self->{expr}->() };	845	my $img = eval { $self->{expr}->() };
800	warn $@ if $@;#d#	846	warn $@ if $@;#d#
801	die if !UNIVERSAL::isa $img, "urxvt::img";	847	die "background-expr did not return an image.\n" if !UNIVERSAL::isa $img, "urxvt::img";
802		848
803	$state->{size_sensitive} = 1	849	$state->{size_sensitive} = 1
804	if $img->repeat_mode != urxvt::RepeatNormal;	850	if $img->repeat_mode != urxvt::RepeatNormal;
805		851
806	# if the expression is sensitive to external events, prepare reevaluation then	852	# if the expression is sensitive to external events, prepare reevaluation then
…		…
856	}	902	}
857		903
858	sub on_start {	904	sub on_start {
859	my ($self) = @_;	905	my ($self) = @_;
860		906
861	my $expr = $self->x_resource ("background.expr")	907	my $expr = $self->x_resource ("%.expr")
862	or return;	908	or return;
863		909
		910	$self->has_render
		911	or die "background extension needs RENDER extension 0.10 or higher, ignoring background-expr.\n";
		912
864	$self->set_expr (parse_expr $expr);	913	$self->set_expr (parse_expr $expr);
865	$self->{border} = $self->x_resource_boolean ("background.border");	914	$self->{border} = $self->x_resource_boolean ("%.border");
866		915
867	$MIN_INTERVAL = $self->x_resource ("background.interval");	916	$MIN_INTERVAL = $self->x_resource ("%.interval");
868		917
869	()	918	()
870	}	919	}
871		920

Diff Legend

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

Comparing rxvt-unicode/src/perl/background (file contents): Revision 1.46 by root, Sun Jun 10 13:32:55 2012 UTC vs. Revision 1.52 by root, Tue Jun 12 10:45:53 2012 UTC

Diff Legend

Comparing rxvt-unicode/src/perl/background (file contents):
Revision 1.46 by root, Sun Jun 10 13:32:55 2012 UTC vs.
Revision 1.52 by root, Tue Jun 12 10:45:53 2012 UTC