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

Comparing rxvt-unicode/src/perl/background (file contents):
Revision 1.50 by root, Sun Jun 10 17:31:53 2012 UTC vs.
Revision 1.54 by root, Thu Jun 14 16:22:20 2012 UTC

…		…
57		57
58	For example, an expression such as C<scale load "$HOME/mybg.png"> scales the	58	For example, an expression such as C<scale load "$HOME/mybg.png"> scales the
59	image to the window size, so it relies on the window size and will	59	image to the window size, so it relies on the window size and will
60	be reevaluated each time it is changed, but not when it moves for	60	be reevaluated each time it is changed, but not when it moves for
61	example. That ensures that the picture always fills the terminal, even	61	example. That ensures that the picture always fills the terminal, even
62	after it's size changes.	62	after its size changes.
63		63
64	=head2 EXPRESSIONS	64	=head2 EXPRESSIONS
65		65
66	Expressions are normal Perl expressions, in fact, they are Perl blocks -	66	Expressions are normal Perl expressions, in fact, they are Perl blocks -
67	which means you could use multiple lines and statements:	67	which means you could use multiple lines and statements:
…		…
71	return scale load "$HOME/weekday.png";	71	return scale load "$HOME/weekday.png";
72	} else {	72	} else {
73	return scale load "$HOME/sunday.png";	73	return scale load "$HOME/sunday.png";
74	}	74	}
75		75
76	This expression gets evaluated once per hour. It will set F<sunday.png> as	76	This expression is evaluated once per hour. It will set F<sunday.png> as
77	background on Sundays, and F<weekday.png> on all other days.	77	background on Sundays, and F<weekday.png> on all other days.
78		78
79	Fortunately, we expect that most expressions will be much simpler, with	79	Fortunately, we expect that most expressions will be much simpler, with
80	little Perl knowledge needed.	80	little Perl knowledge needed.
81		81
…		…
115	horizontal and vertical dimensions. For example, this halves the image	115	horizontal and vertical dimensions. For example, this halves the image
116	width and doubles the image height:	116	width and doubles the image height:
117		117
118	scale 0.5, 2, load "$HOME/mypic.png"	118	scale 0.5, 2, load "$HOME/mypic.png"
119		119
120	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
121	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:
122		122
123	tile load "$HOME/mypic.png"	123	tile load "$HOME/mypic.png"
124		124
125	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
…		…
151	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
152	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
153	image, it will forget about the first one.	153	image, it will forget about the first one.
154		154
155	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
156	memory, or comserve memory by loading images more often.	156	memory, or conserve memory by loading images more often.
157		157
158	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
159	this:	159	this:
160		160
161	my $img1 = load "img1.png";	161	my $img1 = load "img1.png";
…		…
191	Specifying this flag changes the behaviour, so that the image only	191	Specifying this flag changes the behaviour, so that the image only
192	replaces the background of the character area.	192	replaces the background of the character area.
193		193
194	=item --background-interval seconds	194	=item --background-interval seconds
195		195
196	Since some operations in the underlying XRender extension can effetively	196	Since some operations in the underlying XRender extension can effectively
197	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
198	time between updates, which is normally about 0.1 seconds.	198	time between updates, which is normally about 0.1 seconds.
199		199
200	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
201	interval with this switch.	201	interval with this switch.
202		202
203	=back	203	=back
204		204
205	=cut	205	=cut
206		206
207	our %_IMGCACHE;	207	our %_IMG_CACHE;
		208	our %_ONCE_CACHE;
208	our $HOME;	209	our $HOME;
209	our ($self, $old, $new);	210	our ($self, $old, $new);
210	our ($x, $y, $w, $h);	211	our ($x, $y, $w, $h);
211		212
212	# enforce at least this interval between updates	213	# enforce at least this interval between updates
…		…
228	=item load $path	229	=item load $path
229		230
230	Loads the image at the given C<$path>. The image is set to plane tiling	231	Loads the image at the given C<$path>. The image is set to plane tiling
231	mode.	232	mode.
232		233
233	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>).
234		236
		237	=item load_uc $path
		238
		239	Load uncached - same as load, but does not cache the image. This function
		240	is most useufl if you want to optimise a background expression in some
		241	way.
		242
235	=cut	243	=cut
		244
		245	sub load_uc($) {
		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	$img
		252	}
		253	}
236		254
237	sub load($) {	255	sub load($) {
238	my ($path) = @_;	256	my ($path) = @_;
239		257
240	$new->{load}{$path} = $old->{load}{$path} \|\| $self->new_img_from_file ($path);	258	$new->{load}{$path} = $old->{load}{$path} \|\| load_uc $path;
241	}	259	}
242		260
243	=item root	261	=item root
244		262
245	Returns the root window pixmap, that is, hopefully, the background image	263	Returns the root window pixmap, that is, hopefully, the background image
…		…
250		268
251	=cut	269	=cut
252		270
253	sub root() {	271	sub root() {
254	$new->{rootpmap_sensitive} = 1;	272	$new->{rootpmap_sensitive} = 1;
255	die "root op not supported, exg, we need you";	273	$self->new_img_from_root
256	}	274	}
257		275
258	=item solid $colour	276	=item solid $colour
259		277
260	=item solid $width, $height, $colour	278	=item solid $width, $height, $colour
…		…
283	=cut	301	=cut
284		302
285	sub clone($) {	303	sub clone($) {
286	$_[0]->clone	304	$_[0]->clone
287	}	305	}
288
289	=back
290		306
291	=head2 TILING MODES	307	=head2 TILING MODES
292		308
293	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
294	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.
…		…
324	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
325	image over another image or the background colour while leaving all	341	image over another image or the background colour while leaving all
326	background pixels outside the image unchanged.	342	background pixels outside the image unchanged.
327		343
328	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
329	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
330	in alpha mode, else background colour).	346	in alpha mode, else background colour).
331		347
332	pad load "mybg.png"	348	pad load "mybg.png"
333		349
334	=item extend $img	350	=item extend $img
335		351
336	Extends the image over the whole plane, using the closest pixel in the	352	Extends the image over the whole plane, using the closest pixel in the
337	area outside the image. This mode is mostly useful when you more complex	353	area outside the image. This mode is mostly useful when you use more complex
338	filtering operations and want the pixels outside the image to have the	354	filtering operations and want the pixels outside the image to have the
339	same values as the pixels near the edge.	355	same values as the pixels near the edge.
340		356
341	Example: just for curiosity, how does this pixel extension stuff work?	357	Example: just for curiosity, how does this pixel extension stuff work?
342		358
…		…
433	C<$seconds> seconds.	449	C<$seconds> seconds.
434		450
435	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
436	the hour pointer of a clock). Update this image every minute.	452	the hour pointer of a clock). Update this image every minute.
437		453
438	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"
439		455
440	=item counter $seconds	456	=item counter $seconds
441		457
442	Like C<again>, but also returns an increasing counter value, starting at	458	Like C<again>, but also returns an increasing counter value, starting at
443	0, which might be useful for some simple animation effects.	459	0, which might be useful for some simple animation effects.
…		…
630		646
631	sub rootalign($) {	647	sub rootalign($) {
632	move -TX, -TY, $_[0]	648	move -TX, -TY, $_[0]
633	}	649	}
634		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($$$$) {
		664	my $img = pop;
		665	$img->rotate (
		666	$_[0] * $img->w,
		667	$_[1] * $img->h,
		668	$_[2] * (3.14159265 / 180),
		669	)
		670	}
		671
635	=back	672	=back
636		673
637	=head2 COLOUR MODIFICATIONS	674	=head2 COLOUR MODIFICATIONS
638		675
639	The following operators change the pixels of the image.	676	The following operators change the pixels of the image.
…		…
673		710
674	Values less than 0 reduce brightness, while values larger than 0 increase	711	Values less than 0 reduce brightness, while values larger than 0 increase
675	it. Useful range is from -1 to 1 - the former results in a black, the	712	it. Useful range is from -1 to 1 - the former results in a black, the
676	latter in a white picture.	713	latter in a white picture.
677		714
678	Due to idiosynchrasies in the underlying XRender extension, biases less	715	Due to idiosyncrasies in the underlying XRender extension, biases less
679	than zero can be I<very> slow.	716	than zero can be I<very> slow.
680		717
681	=cut	718	=cut
682		719
683	sub contrast($$;$$;$) {	720	sub contrast($$;$$;$) {
…		…
721	sub blur($$;$) {	758	sub blur($$;$) {
722	my $img = pop;	759	my $img = pop;
723	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])	760	$img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0])
724	}	761	}
725		762
726	=item rotate $new_width, $new_height, $center_x, $center_y, $degrees	763	=back
727		764
728	Rotates the image by C<$degrees> degrees, counter-clockwise, around the	765	=head2 OTHER STUFF
729	pointer at C<$center_x> and C<$center_y> (specified as factor of image
730	width/height), generating a new image with width C<$new_width> and height
731	C<$new_height>.
732		766
733	#TODO# new width, height, maybe more operators?	767	Anything that didn't fit any of the other categories, even after appliyng
		768	force and closing our eyes.
734		769
735	Example: rotate the image by 90 degrees	770	=over 4
736		771
737	=cut	772	=item once { ... }
738		773
739	sub rotate($$$$$$) {	774	This function takes a code block as argument, that is, one or more
740	my $img = pop;	775	statements enclosed by braces.
741	$img->rotate (	776
742	$_[0],	777	The trick is that this code block is only evaluated once - future calls
743	$_[1],	778	will simply return the original image (yes, it should only be used with
744	$_[2] * $img->w,	779	images).
745	$_[3] * $img->h,	780
746	$_[4] * (3.14159265 / 180),	781	This can be extremely useful to avoid redoign the same slow operations
747	)	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 = ();
748	}	809	}
749		810
750	=back	811	=back
751		812
752	=cut	813	=cut

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Comparing rxvt-unicode/src/perl/background (file contents): Revision 1.50 by root, Sun Jun 10 17:31:53 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 1.50 by root, Sun Jun 10 17:31:53 2012 UTC vs.
Revision 1.54 by root, Thu Jun 14 16:22:20 2012 UTC