--- rxvt-unicode/src/perl/background 2012/06/10 13:32:55 1.46 +++ rxvt-unicode/src/perl/background 2021/11/26 18:49:48 1.103 @@ -1,14 +1,24 @@ #! perl -#:META:X_RESOURCE:%.expr:string:background expression -#:META:X_RESOURCE:%.border:boolean:respect the terminal border -#:META:X_RESOURCE:%.interval:seconds:minimum time between updates - -#TODO: once, rootalign +#:META:RESOURCE:%.expr:string:background expression +#:META:RESOURCE:%.border:boolean:respect the terminal border +#:META:RESOURCE:%.interval:seconds:minimum time between updates +#:META:RESOURCE:pixmap:file[;geom]:set image as background +#:META:RESOURCE:backgroundPixmap:file[;geom]:set image as background +#:META:RESOURCE:tr:boolean:set root pixmap as background +#:META:RESOURCE:transparent:boolean:set root pixmap as background +#:META:RESOURCE:tint:color:tint background with color +#:META:RESOURCE:tintColor:color:tint background with color +#:META:RESOURCE:sh:number:shade background by number % +#:META:RESOURCE:shading:number:shade background by number % +#:META:RESOURCE:blr:HxV:gaussian-blur background with radii +#:META:RESOURCE:blurRadius:HxV:gaussian-blur background with radii +#:META:OSC:20:change/query background image +#:META:OSC:705:change transparent background tint colour =head1 NAME - background - manage terminal background +background - manage terminal background =head1 SYNOPSIS @@ -16,6 +26,30 @@ --background-border --background-interval seconds +=head1 QUICK AND DIRTY CHEAT SHEET + +Load a random jpeg image and tile the background with it without scaling +or anything else: + + load "/path/to/img.jpg" + +The same, but use mirroring/reflection instead of tiling: + + mirror load "/path/to/img.jpg" + +Load an image and scale it to exactly fill the terminal window: + + scale keep { load "/path/to/img.jpg" } + +Implement pseudo-transparency by using a suitably-aligned root pixmap +as window background: + + rootalign root + +Likewise, but keep a blurred copy: + + rootalign keep { blur 10, root } + =head1 DESCRIPTION This extension manages the terminal background by creating a picture that @@ -30,11 +64,11 @@ For example, to load an image and scale it to the window size, you would use: - urxvt --background-expr 'scale load "/path/to/mybg.png"' + urxvt --background-expr 'scale keep { load "/path/to/mybg.png" }' Or specified as a X resource: - URxvt.background-expr: scale load "/path/to/mybg.png" + URxvt.background.expr: scale keep { load "/path/to/mybg.png" } =head1 THEORY OF OPERATION @@ -57,26 +91,29 @@ pixmap is replaced by another one the root background changes; or when the timer elapses), then the expression will be evaluated again. -For example, an expression such as C scales the -image to the window size, so it relies on the window size and will -be reevaluated each time it is changed, but not when it moves for +For example, an expression such as C scales the image to the window size, so it relies on the window size +and will be reevaluated each time it is changed, but not when it moves for example. That ensures that the picture always fills the terminal, even -after it's size changes. +after its size changes. =head2 EXPRESSIONS Expressions are normal Perl expressions, in fact, they are Perl blocks - which means you could use multiple lines and statements: - again 3600; - if (localtime now)[6]) { - return scale load "$HOME/weekday.png"; - } else { - return scale load "$HOME/sunday.png"; + scale keep { + again 3600; + if (localtime now)[6]) { + return load "$HOME/weekday.png"; + } else { + return load "$HOME/sunday.png"; + } } -This expression gets evaluated once per hour. It will set F as -background on Sundays, and F on all other days. +This inner expression is evaluated once per hour (and whenever the +terminal window is resized). It sets F as background on +Sundays, and F on all other days. Fortunately, we expect that most expressions will be much simpler, with little Perl knowledge needed. @@ -109,7 +146,7 @@ scale 2, load "$HOME/mypic.png" This enlarges the image by a factor of 2 (200%). As you can see, C -has now two arguments, the C<200> and the C expression, while +has now two arguments, the C<2> and the C expression, while C only has one argument. Arguments are separated from each other by commas. @@ -119,67 +156,114 @@ scale 0.5, 2, load "$HOME/mypic.png" -Other effects than scalign are also readily available, for exmaple, you can -tile the image to fill the whole window, instead of resizing it: +IF you try out these expressions, you might suffer from some sluggishness, +because each time the terminal is resized, it loads the PNG image again +and scales it. Scaling is usually fast (and unavoidable), but loading the +image can be quite time consuming. This is where C comes in handy: + + scale 0.5, 2, keep { load "$HOME/mypic.png" } + +The C operator executes all the statements inside the braces only +once, or when it thinks the outcome might change. In other cases it +returns the last value computed by the brace block. + +This means that the C is only executed once, which makes it much +faster, but also means that more memory is being used, because the loaded +image must be kept in memory at all times. In this expression, the +trade-off is likely worth it. + +But back to effects: Other effects than scaling are also readily +available, for example, you can tile the image to fill the whole window, +instead of resizing it: - tile load "$HOME/mypic.png" + tile keep { load "$HOME/mypic.png" } -In fact, images returned by C are in C mode by default, so the C operator -is kind of superfluous. +In fact, images returned by C are in C mode by default, so the +C operator is kind of superfluous. -Another common effect is to mirror the image, so that the same edges touch: +Another common effect is to mirror the image, so that the same edges +touch: - mirror load "$HOME/mypic.png" + mirror keep { load "$HOME/mypic.png" } -This is also a typical background expression: +Another common background expression is: rootalign root -It first takes a snapshot of the screen background image, and then -moves it to the upper left corner of the screen - the result is -pseudo-transparency, as the image seems to be static while the window is -moved around. +This one first takes a snapshot of the screen background image, and then +moves it to the upper left corner of the screen (as opposed to the upper +left corner of the terminal window)- the result is pseudo-transparency: +the image seems to be static while the window is moved around. -=head2 CYCLES AND CACHING +=head2 COLOUR SPECIFICATIONS -As has been mentioned before, the expression might be evaluated multiple -times. Each time the expression is reevaluated, a new cycle is said to -have begun. Many operators cache their results till the next cycle. +Whenever an operator expects a "colour", then this can be specified in one +of two ways: Either as string with an X11 colour specification, such as: -For example, the C operator keeps a copy of the image. If it is -asked to load the same image on the next cycle it will not load it again, -but return the cached copy. + "red" # named colour + "#f00" # simple rgb + "[50]red" # red with 50% alpha + "TekHVC:300/50/50" # anything goes -This only works for one cycle though, so as long as you load the same -image every time, it will always be cached, but when you load a different -image, it will forget about the first one. +OR as an array reference with one, three or four components: -This allows you to either speed things up by keeping multiple images in -memory, or comserve memory by loading images more often. + [0.5] # 50% gray, 100% alpha + [0.5, 0, 0] # dark red, no green or blur, 100% alpha + [0.5, 0, 0, 0.7] # same with explicit 70% alpha -For example, you can keep two images in memory and use a random one like -this: +=head2 CACHING AND SENSITIVITY - my $img1 = load "img1.png"; - my $img2 = load "img2.png"; - (0.5 > rand) ? $img1 : $img2 +Since some operations (such as C and C) can take a long time, +caching results can be very important for a smooth operation. Caching can +also be useful to reduce memory usage, though, for example, when an image +is cached by C, it could be shared by multiple terminal windows +running inside urxvtd. -Since both images are "loaded" every time the expression is evaluated, -they are always kept in memory. Contrast this version: +=head3 C caching - my $path1 = "img1.png"; - my $path2 = "img2.png"; - load ((0.5 > rand) ? $path1 : $path2) +The most important way to cache expensive operations is to use C. The C operator takes a block of multiple statements enclosed +by C<{}> and keeps the return value in memory. -Here, a path is selected randomly, and load is only called for one image, -so keeps only one image in memory. If, on the next evaluation, luck -decides to use the other path, then it will have to load that image again. +An expression can be "sensitive" to various external events, such as +scaling or moving the window, root background changes and timers. Simply +using an expression (such as C without parameters) that depends on +certain changing values (called "variables"), or using those variables +directly, will make an expression sensitive to these events - for example, +using C or C will make the expression sensitive to the terminal +size, and thus to resizing events. + +When such an event happens, C will automatically trigger a +reevaluation of the whole expression with the new value of the expression. + +C is most useful for expensive operations, such as C: + + rootalign keep { blur 20, root } + +This makes a blurred copy of the root background once, and on subsequent +calls, just root-aligns it. Since C is usually quite slow and +C is quite fast, this trades extra memory (for the cached +blurred pixmap) with speed (blur only needs to be redone when root +changes). + +=head3 C caching + +The C operator itself does not keep images in memory, but as long as +the image is still in memory, C will use the in-memory image instead +of loading it freshly from disk. + +That means that this expression: + + keep { load "$HOME/path..." } + +Not only caches the image in memory, other terminal instances that try to +C it can reuse that in-memory copy. =head1 REFERENCE =head2 COMMAND LINE SWITCHES -=over 4 +=over =item --background-expr perl-expression @@ -195,7 +279,7 @@ =item --background-interval seconds -Since some operations in the underlying XRender extension can effetively +Since some operations in the underlying XRender extension can effectively freeze your X-server for prolonged time, this extension enforces a minimum time between updates, which is normally about 0.1 seconds. @@ -206,9 +290,10 @@ =cut +our %_IMG_CACHE; our $HOME; -our ($self, $old, $new); -our ($x, $y, $w, $h); +our ($self, $frame); +our ($x, $y, $w, $h, $focus); # enforce at least this interval between updates our $MIN_INTERVAL = 6/59.951; @@ -216,6 +301,11 @@ { package urxvt::bgdsl; # background language + sub FR_PARENT() { 0 } # parent frame, if any - must be #0 + sub FR_CACHE () { 1 } # cached values + sub FR_AGAIN () { 2 } # what this expr is sensitive to + sub FR_STATE () { 3 } # watchers etc. + use List::Util qw(min max sum shuffle); =head2 PROVIDERS/GENERATORS @@ -224,27 +314,42 @@ from the root screen or by simply generating it. They are used as starting points to get an image you can play with. -=over 4 +=over =item load $path Loads the image at the given C<$path>. The image is set to plane tiling mode. -Loaded images will be cached for one cycle. +If the image is already in memory (e.g. because another terminal instance +uses it), then the in-memory copy is returned instead. + +=item load_uc $path + +Load uncached - same as load, but does not cache the image, which means it +is I loaded from the filesystem again, even if another copy of it +is in memory at the time. =cut + sub load_uc($) { + $self->new_img_from_file ($_[0]) + } + sub load($) { my ($path) = @_; - $new->{load}{$path} = $old->{load}{$path} || $self->new_img_from_file ($path); + $_IMG_CACHE{$path} || do { + my $img = load_uc $path; + Scalar::Util::weaken ($_IMG_CACHE{$path} = $img); + $img + } } =item root Returns the root window pixmap, that is, hopefully, the background image -of your screen. The image is set to extend mode. +of your screen. This function makes your expression root sensitive, that means it will be reevaluated when the bg image changes. @@ -252,8 +357,8 @@ =cut sub root() { - $new->{rootpmap_sensitive} = 1; - die "root op not supported, exg, we need you"; + $frame->[FR_AGAIN]{rootpmap} = 1; + $self->new_img_from_root } =item solid $colour @@ -271,7 +376,7 @@ sub solid($;$$) { my $colour = pop; - my $img = $self->new_img (urxvt::PictStandardARGB32, $_[0] || 1, $_[1] || 1); + my $img = $self->new_img (urxvt::PictStandardARGB32, 0, 0, $_[0] || 1, $_[1] || 1); $img->fill ($colour); $img } @@ -287,6 +392,50 @@ $_[0]->clone } +=item merge $img ... + +Takes any number of images and merges them together, creating a single +image containing them all. The tiling mode of the first image is used as +the tiling mode of the resulting image. + +This function is called automatically when an expression returns multiple +images. + +=cut + + sub merge(@) { + return $_[0] unless $#_; + + # rather annoyingly clumsy, but optimisation is for another time + + my $x0 = +1e9; + my $y0 = +1e9; + my $x1 = -1e9; + my $y1 = -1e9; + + for (@_) { + my ($x, $y, $w, $h) = $_->geometry; + + $x0 = $x if $x0 > $x; + $y0 = $y if $y0 > $y; + + $x += $w; + $y += $h; + + $x1 = $x if $x1 < $x; + $y1 = $y if $y1 < $y; + } + + my $base = $self->new_img (urxvt::PictStandardARGB32, $x0, $y0, $x1 - $x0, $y1 - $y0); + $base->repeat_mode ($_[0]->repeat_mode); + $base->fill ([0, 0, 0, 0]); + + $base->draw ($_) + for @_; + + $base + } + =back =head2 TILING MODES @@ -294,7 +443,7 @@ The following operators modify the tiling mode of an image, that is, the way that pixels outside the image area are painted when the image is used. -=over 4 +=over =item tile $img @@ -327,7 +476,7 @@ background pixels outside the image unchanged. Example: load an image and display it in the upper left corner. The rest -of the space is left "empty" (transparent or wahtever your compisotr does +of the space is left "empty" (transparent or whatever your compositor does in alpha mode, else background colour). pad load "mybg.png" @@ -335,7 +484,7 @@ =item extend $img Extends the image over the whole plane, using the closest pixel in the -area outside the image. This mode is mostly useful when you more complex +area outside the image. This mode is mostly useful when you use more complex filtering operations and want the pixels outside the image to have the same values as the pixels near the edge. @@ -379,7 +528,7 @@ example using C (terminal width) means your expression is evaluated again when the terminal is resized. -=over 4 +=over =item TX @@ -389,22 +538,24 @@ window is the full window by default, and the character area only when in border-respect mode). -Using these functions make your expression sensitive to window moves. +Using these functions makes your expression sensitive to window moves. These functions are mainly useful to align images to the root window. Example: load an image and align it so it looks as if anchored to the -background. +background (that's exactly what C does btw.): - move -TX, -TY, load "mybg.png" + move -TX, -TY, keep { load "mybg.png" } =item TW +=item TH + Return the width (C) and height (C) of the terminal window (the terminal window is the full window by default, and the character area only when in border-respect mode). -Using these functions make your expression sensitive to window resizes. +Using these functions makes your expression sensitive to window resizes. These functions are mainly useful to scale images, or to clip images to the window size to conserve memory. @@ -412,14 +563,31 @@ Example: take the screen background, clip it to the window size, blur it a bit, align it to the window position and use it as background. - clip move -TX, -TY, blur 5, root + clip move -TX, -TY, keep { blur 5, root } + +=item FOCUS + +Returns a boolean indicating whether the terminal window has keyboard +focus, in which case it returns true. + +Using this function makes your expression sensitive to focus changes. + +A common use case is to fade the background image when the terminal loses +focus, often together with the C<-fade> command line option. In fact, +there is a special function for just that use case: C. + +Example: use two entirely different background images, depending on +whether the window has focus. + + FOCUS ? keep { load "has_focus.jpg" } : keep { load "no_focus.jpg" } =cut - sub TX() { $new->{position_sensitive} = 1; $x } - sub TY() { $new->{position_sensitive} = 1; $y } - sub TW() { $new->{size_sensitive} = 1; $w } - sub TH() { $new->{size_sensitive} = 1; $h } + sub TX () { $frame->[FR_AGAIN]{position} = 1; $x } + sub TY () { $frame->[FR_AGAIN]{position} = 1; $y } + sub TW () { $frame->[FR_AGAIN]{size} = 1; $w } + sub TH () { $frame->[FR_AGAIN]{size} = 1; $h } + sub FOCUS() { $frame->[FR_AGAIN]{focus} = 1; $focus } =item now @@ -436,7 +604,8 @@ Example: load some image and rotate it according to the time of day (as if it were the hour pointer of a clock). Update this image every minute. - again 60; rotate TW, TH, 50, 50, (now % 86400) * -720 / 86400, scale load "myclock.png" + again 60; + rotate 50, 50, (now % 86400) * -72 / 8640, scale keep { load "myclock.png" } =item counter $seconds @@ -448,12 +617,12 @@ sub now() { urxvt::NOW } sub again($) { - $new->{again} = $_[0]; + $frame->[FR_AGAIN]{time} = $_[0]; } sub counter($) { - $new->{again} = $_[0]; - $self->{counter} + 0 + $frame->[FR_AGAIN]{time} = $_[0]; + $frame->[FR_STATE]{counter} + 0 } =back @@ -462,7 +631,7 @@ The following operators modify the shape, size or position of the image. -=over 4 +=over =item clip $img @@ -475,7 +644,7 @@ larger than the image, then the tiling mode defines how the extra pixels will be filled. -If C<$x> an C<$y> are missing, then C<0> is assumed for both. +If C<$x> and C<$y> are missing, then C<0> is assumed for both. If C<$width> and C<$height> are missing, then the window size will be assumed. @@ -483,7 +652,7 @@ Example: load an image, blur it, and clip it to the window size to save memory. - clip blur 10, load "mybg.png" + clip keep { blur 10, load "mybg.png" } =cut @@ -503,7 +672,7 @@ Scales the image by the given factors in horizontal (C<$width>) and vertical (C<$height>) direction. -If only one factor is give, it is used for both directions. +If only one factor is given, it is used for both directions. If no factors are given, scales the image to the window size without keeping aspect. @@ -587,7 +756,7 @@ Example: load an image and center it. - center pad load "mybg.png" + center keep { pad load "mybg.png" } =item rootalign $img @@ -598,7 +767,7 @@ Example: load a background image, put it in mirror mode and root align it. - rootalign mirror load "mybg.png" + rootalign keep { mirror load "mybg.png" } Example: take the screen background and align it, giving the illusion of transparency as long as the window isn't in front of other windows. @@ -633,13 +802,61 @@ move -TX, -TY, $_[0] } +=item rotate $center_x, $center_y, $degrees, $img + +Rotates the image clockwise by C<$degrees> degrees, around the point at +C<$center_x> and C<$center_y> (specified as factor of image width/height). + +Example: rotate the image by 90 degrees around its center. + + rotate 0.5, 0.5, 90, keep { load "$HOME/mybg.png" } + +=cut + + sub rotate($$$$) { + my $img = pop; + $img->rotate ( + $_[0] * ($img->w + $img->x), + $_[1] * ($img->h + $img->y), + $_[2] * (3.14159265 / 180), + ) + } + =back =head2 COLOUR MODIFICATIONS The following operators change the pixels of the image. -=over 4 +=over + +=item tint $color, $img + +Tints the image in the given colour. + +Example: tint the image red. + + tint "red", load "rgb.png" + +Example: the same, but specify the colour by component. + + tint [1, 0, 0], load "rgb.png" + +=cut + + sub tint($$) { + $_[1]->tint ($_[0]) + } + +=item shade $factor, $img + +Shade the image by the given factor. + +=cut + + sub shade($$) { + $_[1]->shade ($_[0]) + } =item contrast $factor, $img @@ -676,17 +893,19 @@ it. Useful range is from -1 to 1 - the former results in a black, the latter in a white picture. -Due to idiosynchrasies in the underlying XRender extension, biases less +Due to idiosyncrasies in the underlying XRender extension, biases less than zero can be I slow. +You can also try the experimental(!) C operator. + =cut sub contrast($$;$$;$) { my $img = pop; my ($r, $g, $b, $a) = @_; - ($g, $b) = ($r, $r) if @_ < 4; - $a = 1 if @_ < 5; + ($g, $b) = ($r, $r) if @_ < 3; + $a = 1 if @_ < 4; $img = $img->clone; $img->contrast ($r, $g, $b, $a); @@ -697,14 +916,34 @@ my $img = pop; my ($r, $g, $b, $a) = @_; - ($g, $b) = ($r, $r) if @_ < 4; - $a = 1 if @_ < 5; + ($g, $b) = ($r, $r) if @_ < 3; + $a = 1 if @_ < 4; $img = $img->clone; $img->brightness ($r, $g, $b, $a); $img } +=item muladd $mul, $add, $img # EXPERIMENTAL + +First multiplies the pixels by C<$mul>, then adds C<$add>. This can be used +to implement brightness and contrast at the same time, with a wider value +range than contrast and brightness operators. + +Due to numerous bugs in XRender implementations, it can also introduce a +number of visual artifacts. + +Example: increase contrast by a factor of C<$c> without changing image +brightness too much. + + muladd $c, (1 - $c) * 0.5, $img + +=cut + + sub muladd($$$) { + $_[2]->muladd ($_[0], $_[1]) + } + =item blur $radius, $img =item blur $radius_horz, $radius_vert, $img @@ -724,39 +963,285 @@ $img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0]) } -=item rotate $new_width, $new_height, $center_x, $center_y, $degrees +=item focus_fade $img + +=item focus_fade $factor, $img -Rotates the image by C<$degrees> degrees, counter-clockwise, around the -pointer at C<$center_x> and C<$center_y> (specified as factor of image -width/height), generating a new image with width C<$new_width> and height -C<$new_height>. +=item focus_fade $factor, $color, $img -#TODO# new width, height, maybe more operators? +Fades the image by the given factor (and colour) when focus is lost (the +same as the C<-fade>/C<-fadecolor> command line options, which also supply +the default values for C and C<$color>. Unlike with C<-fade>, the +C<$factor> is a real value, not a percentage value (that is, 0..1, not +0..100). -Example: rotate the image by 90 degrees +Example: do the right thing when focus fading is requested. + + focus_fade load "mybg.jpg"; =cut - sub rotate($$$$$$) { + sub focus_fade($;$$) { my $img = pop; - $img->rotate ( - $_[0], - $_[1], - $_[2] * $img->w, - $_[3] * $img->h, - $_[4] * (3.14159265 / 180), - ) + + return $img + if FOCUS; + + my $fade = @_ >= 1 ? $_[0] : defined $self->resource ("fade") ? $self->resource ("fade") * 0.01 : 0; + my $color = @_ >= 2 ? $_[1] : $self->resource ("color+" . urxvt::Color_fade); + + $img = $img->tint ($color) if $color ne "rgb:00/00/00"; + $img = $img->muladd (1 - $fade, 0) if $fade; + + $img } =back +=head2 OTHER STUFF + +Anything that didn't fit any of the other categories, even after applying +force and closing our eyes. + +=over + +=item keep { ... } + +This operator takes a code block as argument, that is, one or more +statements enclosed by braces. + +The trick is that this code block is only evaluated when the outcome +changes - on other calls the C simply returns the image it computed +previously (yes, it should only be used with images). Or in other words, +C I the result of the code block so it doesn't need to be +computed again. + +This can be extremely useful to avoid redoing slow operations - for +example, if your background expression takes the root background, blurs it +and then root-aligns it it would have to blur the root background on every +window move or resize. + +Another example is C, which can be quite slow. + +In fact, urxvt itself encloses the whole expression in some kind of +C block so it only is reevaluated as required. + +Putting the blur into a C block will make sure the blur is only done +once, while the C is still done each time the window moves. + + rootalign keep { blur 10, root } + +This leaves the question of how to force reevaluation of the block, +in case the root background changes: If expression inside the block +is sensitive to some event (root background changes, window geometry +changes), then it will be reevaluated automatically as needed. + +=back + +=head1 OLD BACKGROUND IMAGE SETTINGS + +This extension also provides support for the old options/resources and +OSC sequences for setting a background image. These settings are +B and will be removed in future versions. + +=head2 OPTIONS AND RESOURCES + +=over + +=item B<-pixmap> I + +=item B I + +Use the specified image file as the window's background and also +optionally specify a colon separated list of operations to modify it. +Note that you may need to quote the C<;> character when using the +command line option, as C<;> is usually a metacharacter in shells. +Supported operations are: + +=over + +=item B + +sets scale and position. B<"W" / "H"> specify the horizontal/vertical +scale (percent), and B<"X" / "Y"> locate the image centre (percent). A +scale of 0 disables scaling. + +=item B + +enables tiling + +=item B + +maintain the image aspect ratio when scaling + +=item B + +use the position of the terminal window relative to the root window as +the image offset, simulating a root window background + +=back + +The default scale and position setting is C<100x100+50+50>. +Alternatively, a predefined set of templates can be used to achieve +the most common setups: + +=over + +=item B + +the image is tiled with no scaling. Equivalent to 0x0+0+0:op=tile + +=item B + +the image is scaled to fill the whole window maintaining the aspect +ratio and centered. Equivalent to 100x100+50+50:op=keep-aspect + +=item B + +the image is scaled to fill the whole window. Equivalent to 100x100 + +=item B + +the image is centered with no scaling. Equivalent to 0x0+50+50 + +=item B + +the image is tiled with no scaling and using 'root' positioning. +Equivalent to 0x0:op=tile:op=root-align + +=back + +If multiple templates are specified the last one wins. Note that a +template overrides all the scale, position and operations settings. + +If used in conjunction with pseudo-transparency, the specified image +will be blended over the transparent background using alpha-blending. + +=item B<-tr>|B<+tr> + +=item B I + +Turn on/off pseudo-transparency by using the root pixmap as background. + +=item B<-tint> I + +=item B I + +Tint the transparent background with the given colour. Note that a +black tint yields a completely black image while a white tint yields +the image unchanged. + +=item B<-sh> I + +=item B I + +Darken (0 .. 99) or lighten (101 .. 200) the transparent background. +A value of 100 means no shading. + +=item B<-blr> I + +=item B I + +Apply gaussian blur with the specified radius to the transparent +background. If a single number is specified, the vertical and +horizontal radii are considered to be the same. Setting one of the +radii to 1 and the other to a large number creates interesting effects +on some backgrounds. The maximum radius value is 128. An horizontal or +vertical radius of 0 disables blurring. + +=back + +=head2 OSC sequences + +This extension will react to the following OSC sequences. Note that +this extension will not be autoloaded when these are used currently, +so to make urxvt recognize them, you have to enable the C +extension. One way to achieve that is to use the C<--background-expr ''> +command line argument or by specifying an empty C> +resource. + +=over + +=item B<< C >> Change transparent background tint colour to B<< C >>. + +=item B<< C >> Change/Query background image +parameters: the value of B<< C >> can be one of the following +commands: + +=over + +=item B<< C >> + +display scale and position in the title + +=item B<< C<;WxH+X+Y> >> + +change scale and/or position + +=item B<< C >> + +change background image + +=back + +=cut + + sub keep(&) { + my $id = $_[0]+0; + + local $frame = $self->{frame_cache}{$id} ||= [$frame]; + + unless ($frame->[FR_CACHE]) { + $frame->[FR_CACHE] = [ $_[0]() ]; + + my $self = $self; + my $frame = $frame; + Scalar::Util::weaken $frame; + $self->compile_frame ($frame, sub { + # clear this frame cache, also for all parents + for (my $frame = $frame; $frame; $frame = $frame->[0]) { + undef $frame->[FR_CACHE]; + } + + $self->recalculate; + }); + }; + + # in scalar context we always return the first original result, which + # is not quite how perl works. + wantarray + ? @{ $frame->[FR_CACHE] } + : $frame->[FR_CACHE][0] + } + +# sub keep_clear() { +# delete $self->{frame_cache}; +# } + +=back + =cut } sub parse_expr { - my $expr = eval "sub {\npackage urxvt::bgdsl;\n#line 0 'background expression'\n$_[0]\n}"; - die if $@; + my ($expr) = @_; + + # an empty expression is valid and represents the default background + if ($expr !~ /\S/) { + $expr = sub { + undef + }; + } else { + $expr = eval + "sub {\n" + . "package urxvt::bgdsl;\n" + . "#line 0 'background expression'\n" + . "$expr\n" + . "}"; + die if $@; + } + $expr } @@ -764,10 +1249,65 @@ sub set_expr { my ($self, $expr) = @_; + $self->{root} = []; # the outermost frame $self->{expr} = $expr; $self->recalculate; } +# takes a hash of sensitivity indicators and installs watchers +sub compile_frame { + my ($self, $frame, $cb) = @_; + + my $state = $frame->[urxvt::bgdsl::FR_STATE] ||= {}; + my $again = $frame->[urxvt::bgdsl::FR_AGAIN]; + + # don't keep stuff alive + Scalar::Util::weaken $state; + + if ($again->{nested}) { + $state->{nested} = 1; + } else { + delete $state->{nested}; + } + + if (my $interval = $again->{time}) { + $state->{time} = [$interval, urxvt::timer->new->after ($interval)->interval ($interval)] + if $state->{time}[0] != $interval; + + # callback *might* have changed, although we could just rule that out + $state->{time}[1]->cb (sub { + ++$state->{counter}; + $cb->(); + }); + } else { + delete $state->{time}; + } + + if ($again->{position}) { + $state->{position} = $self->on (position_change => $cb); + } else { + delete $state->{position}; + } + + if ($again->{size}) { + $state->{size} = $self->on (size_change => $cb); + } else { + delete $state->{size}; + } + + if ($again->{rootpmap}) { + $state->{rootpmap} = $self->on (rootpmap_change => $cb); + } else { + delete $state->{rootpmap}; + } + + if ($again->{focus}) { + $state->{focus} = $self->on (focus_in => $cb, focus_out => $cb); + } else { + delete $state->{focus}; + } +} + # evaluate the current bg expression sub recalculate { my ($arg_self) = @_; @@ -783,89 +1323,288 @@ $arg_self->{next_refresh} = urxvt::NOW + $MIN_INTERVAL; - # set environment to evaluate user expression + unless ($arg_self->has_render) { + warn "background extension needs RENDER extension 0.11 or higher, ignoring background-expr.\n"; + return; + } - local $self = $arg_self; + # set environment to evaluate user expression - local $HOME = $ENV{HOME}; - local $old = $self->{state}; - local $new = my $state = $self->{state} = {}; + local $self = $arg_self; + local $HOME = $ENV{HOME}; + local $frame = $self->{root}; - ($x, $y, $w, $h) = - $self->background_geometry ($self->{border}); + ($x, $y, $w, $h) = $self->background_geometry ($self->{border}); + $focus = $self->focus; # evaluate user expression - my $img = eval { $self->{expr}->() }; - warn $@ if $@;#d# - die if !UNIVERSAL::isa $img, "urxvt::img"; - - $state->{size_sensitive} = 1 - if $img->repeat_mode != urxvt::RepeatNormal; - - # if the expression is sensitive to external events, prepare reevaluation then - - my $repeat; - - if (my $again = $state->{again}) { - $repeat = 1; - my $self = $self; - $state->{timer} = $again == $old->{again} - ? $old->{timer} - : urxvt::timer->new->after ($again)->interval ($again)->cb (sub { - ++$self->{counter}; - $self->recalculate - }); - } - - if (delete $state->{position_sensitive}) { - $repeat = 1; - $self->enable (position_change => sub { $_[0]->recalculate }); + my @img = eval { $self->{expr}->() }; + die $@ if $@; + die "background-expr did not return anything.\n" unless @img; + + if ($img[0]) { + die "background-expr: expected image(s), got something else.\n" + if grep { !UNIVERSAL::isa $_, "urxvt::img" } @img; + + my $img = urxvt::bgdsl::merge @img; + + $frame->[urxvt::bgdsl::FR_AGAIN]{size} = 1 + if $img->repeat_mode != urxvt::RepeatNormal; + + # if the expression is sensitive to external events, prepare reevaluation then + $self->compile_frame ($frame, sub { $arg_self->recalculate }); + + # clear stuff we no longer need + +# unless (%{ $frame->[FR_STATE] }) { +# delete $self->{state}; +# delete $self->{expr}; +# } + + # set background pixmap + + $self->set_background ($img, $self->{border}); } else { - $self->disable ("position_change"); + $self->clr_background; } - if (delete $state->{size_sensitive}) { - $repeat = 1; - $self->enable (size_change => sub { $_[0]->recalculate }); - } else { - $self->disable ("size_change"); + $self->scr_recolor (0); + $self->want_refresh; +} + +sub old_bg_opts { + my ($self, $arg) = @_; + + $arg or return; + + my @str = split /;/, $arg; + + return unless $str[0] or $self->{bg_opts}->{path}; + + my $bg_opts = $self->{bg_opts}; + + if ($str[0]) { + $bg_opts->{tile} = 0; + $bg_opts->{keep_aspect} = 0; + $bg_opts->{root_align} = 0; + $bg_opts->{h_scale} = $bg_opts->{v_scale} = 100; + $bg_opts->{h_align} = $bg_opts->{v_align} = 50; + $bg_opts->{path} = $str[0]; + } + + my @oplist = split /:/, $str[1]; + + for (@oplist) { + if (/style=tiled/i) { + $bg_opts->{tile} = 1; + $bg_opts->{keep_aspect} = 0; + $bg_opts->{root_align} = 0; + $bg_opts->{h_scale} = $bg_opts->{v_scale} = 0; + $bg_opts->{h_align} = $bg_opts->{v_align} = 0; + } elsif (/style=aspect-stretched/i) { + $bg_opts->{tile} = 0; + $bg_opts->{keep_aspect} = 1; + $bg_opts->{root_align} = 0; + $bg_opts->{h_scale} = $bg_opts->{v_scale} = 100; + $bg_opts->{h_align} = $bg_opts->{v_align} = 50; + } elsif (/style=stretched/i) { + $bg_opts->{tile} = 0; + $bg_opts->{keep_aspect} = 0; + $bg_opts->{root_align} = 0; + $bg_opts->{h_scale} = $bg_opts->{v_scale} = 100; + $bg_opts->{h_align} = $bg_opts->{v_align} = 50; + } elsif (/style=centered/i) { + $bg_opts->{tile} = 0; + $bg_opts->{keep_aspect} = 0; + $bg_opts->{root_align} = 0; + $bg_opts->{h_scale} = $bg_opts->{v_scale} = 0; + $bg_opts->{h_align} = $bg_opts->{v_align} = 50; + } elsif (/style=root-tiled/i) { + $bg_opts->{tile} = 1; + $bg_opts->{keep_aspect} = 0; + $bg_opts->{root_align} = 1; + $bg_opts->{h_scale} = $bg_opts->{v_scale} = 0; + $bg_opts->{h_align} = $bg_opts->{v_align} = 0; + } elsif (/op=tile/i) { + $bg_opts->{tile} = 1; + } elsif (/op=keep-aspect/i) { + $bg_opts->{keep_aspect} = 1; + } elsif (/op=root-align/i) { + $bg_opts->{root_align} = 1; + } elsif (/^ =? ([0-9]+)? (?:[xX] ([0-9]+))? ([+-][0-9]+)? ([+-][0-9]+)? $/x) { + my ($w, $h, $x, $y) = ($1, $2, $3, $4); + + if ($str[0]) { + $w = $h unless defined $w; + $h = $w unless defined $h; + $y = $x unless defined $y; + } + + $bg_opts->{h_scale} = $w if defined $w; + $bg_opts->{v_scale} = $h if defined $h; + $bg_opts->{h_align} = $x if defined $x; + $bg_opts->{v_align} = $y if defined $y; + } } +} - if (delete $state->{rootpmap_sensitive}) { - $repeat = 1; - $self->enable (rootpmap_change => sub { $_[0]->recalculate }); - } else { - $self->disable ("rootpmap_change"); +# helper function, quote string as perl without allowing +# any code execution or other shenanigans. does not +# support binary NULs in string. +sub q0 { + (my $str = shift) =~ s/\x00//g; # make sure there really aren't any embedded NULs + "q\x00$str\x00" +} + +sub old_bg_expr { + my ($self) = @_; + + my $expr; + + my $bg_opts = $self->{bg_opts}; + + if ($bg_opts->{root} =~ /^\s*(?:true|yes|on|1)\s*$/i) { + $expr .= "tile ("; + + my $shade = $bg_opts->{shade}; + + if ($shade) { + $shade = List::Util::min $shade, 200; + $shade = List::Util::max $shade, -100; + $shade = 200 - (100 + $shade) if $shade < 0; + + $shade = $shade * 0.01 - 1; + $expr .= "shade $shade, "; + } + + my $tint = $bg_opts->{tint}; + + if ($tint) { + $tint = q0 $tint; + $expr .= "tint $tint,"; + } + + my $blur = $bg_opts->{blur}; + + if ($blur and $blur =~ /^ =? ([0-9]+)? (?:[xX] ([0-9]+))? $/x) { + my $hr = defined $1 ? $1 : 1; + my $vr = defined $2 ? $2 : $hr; + + if ($hr != 0 and $vr != 0) { + $expr .= "blur $hr, $vr, "; + } + } + + $expr .= "rootalign root)"; } - # clear stuff we no longer need + if ($bg_opts->{path}) { + my $file_expr; + my $h_scale = $bg_opts->{h_scale} * 0.01; + my $v_scale = $bg_opts->{v_scale} * 0.01; + my $h_align = $bg_opts->{h_align} * 0.01; + my $v_align = $bg_opts->{v_align} * 0.01; + + if (!$bg_opts->{tile}) { + $file_expr .= "pad ("; + } else { + $file_expr .= "tile ("; + } + + if ($bg_opts->{root_align}) { + $file_expr .= "rootalign "; + } else { + $file_expr .= "align $h_align, $v_align, "; + } - %$old = (); + if ($h_scale != 0 and $v_scale != 0) { + my $op = $bg_opts->{keep_aspect} ? "fit" : "resize"; + $file_expr .= "$op TW * $h_scale, TH * $v_scale, "; + } - unless ($repeat) { - delete $self->{state}; - delete $self->{expr}; + my $path = q0 $bg_opts->{path}; + + $file_expr .= "keep { load $path })"; + + if ($expr) { + $expr .= ", tint (\"[50]white\", $file_expr)"; + } else { + $expr = $file_expr; + } } - # set background pixmap + $expr +} + +sub find_resource { + my ($self, $res, $opt) = @_; - $self->set_background ($img, $self->{border}); - $self->scr_recolour (0); - $self->want_refresh; + my $v = $self->x_resource ($opt); + $v = $self->x_resource ($res) unless defined $v; + + $v } -sub on_start { +sub parse_bgopts { my ($self) = @_; - my $expr = $self->x_resource ("background.expr") - or return; + my $expr = $self->x_resource ("%.expr"); + + if (!$expr) { + $self->{bg_opts} = { h_scale => 100, v_scale => 100, + h_align => 50, v_align => 50 }; + + $self->{bg_opts}{shade} = $self->find_resource ("shading", "sh"); + $self->{bg_opts}{tint} = $self->find_resource ("tintColor", "tint"); + $self->{bg_opts}{blur} = $self->find_resource ("blurRadius", "blr"); + $self->{bg_opts}{root} = $self->find_resource ("transparent", "tr"); + + $self->old_bg_opts ($self->find_resource ("backgroundPixmap", "pixmap")); + $expr = $self->old_bg_expr; + } $self->set_expr (parse_expr $expr); - $self->{border} = $self->x_resource_boolean ("background.border"); + $self->{border} = $self->x_resource_boolean ("%.border"); + + $MIN_INTERVAL = $self->x_resource ("%.interval"); +} + +sub on_start { + my ($self) = @_; - $MIN_INTERVAL = $self->x_resource ("background.interval"); + $self->parse_bgopts; () } +sub on_osc_seq { + my ($self, $op, $arg) = @_; + + $op eq "20" or $op eq "706" + or return; + + $self->{bg_opts} + or $self->parse_bgopts; + + if ($op eq "20") { + if ($arg eq "?") { + my $h_scale = $self->{bg_opts}{h_scale}; + my $v_scale = $self->{bg_opts}{v_scale}; + my $h_align = $self->{bg_opts}{h_align}; + my $v_align = $self->{bg_opts}{v_align}; + $self->cmd_parse ("\033]2;[${h_scale}x${v_scale}+${h_align}+${v_align}]\007"); + } else { + $self->old_bg_opts ($arg); + my $expr = $self->old_bg_expr; + $self->set_expr (parse_expr $expr) if $expr; + } + } elsif ($op eq "705") { + $self->{bg_opts}{tint} = $arg; + my $expr = $self->old_bg_expr; + $self->set_expr (parse_expr $expr) if $expr; + } + + 1 +} +