Screenly Cast

FAQ

When do I use “?srly” and when do I use “&srly”?

Use ?srly when the URL has no other parameters:

• https://www.mydomain.com/some-page?srly

Use &srly when it already has some:

• https://www.mydomain.com/?somevar=1&anothervar=2&srly

The parameter needs no value. ?srly on its own is enough.

How are signage players recognized?

From their request: the X-Screenly-* metadata headers a Screenly player can
send, the Android package name several other players identify themselves with,
and user agent tokens that name a player and nothing else: Screenly, Anthias,
BrightSign, IAdea, Slideshow and Unifi Connect.

Detection is deliberately cautious, because the two kinds of mistake are not
equally bad. A player it misses still works if you add ?srly. A device it
wrongly claims would show a signage render to somebody who was just browsing,
with no explanation and no way back.

So a signal has to name a player and nothing else. Notably absent: LG webOS and
Samsung Tizen, which run signage displays and every LG and Samsung smart TV,
and QtWebEngine, which signage players embed and so does any desktop Qt
application. Search engines, signed-in users and meeting-room devices are
excluded too: a room calendar is not signage.

A detected player is sent to the same URL with ?srly added rather than being
shown signage on the original URL, so that a page cache or CDN never has to serve
two different pages for one URL. Only the redirect itself is uncacheable.

Turn it off under Settings → Screenly Cast if you would rather add ?srly
yourself, or use the screenly_cast_is_signage_player filter to widen or narrow
which requests count.

Does this change my site’s theme?

No. A signage request renders through the plugin’s own template for that one
request. Your active theme, and what every other visitor sees, is unaffected.

Versions up to 1.0.5 did switch the site’s theme, and could leave a site stuck on
the bundled Screenly Cast theme. On upgrade this plugin detects that, switches
your original theme back, and tells you it has done so.

How much text will be shown?

Assume a couple of hundred characters will be comfortably read at a distance.
Longer content is trimmed to what fits rather than overflowing or scrolling.

If you need a different limit, filter it:

add_filter( 'screenly_cast_character_budget', fn() => 900 );

Can I allow more HTML tags in signage content?

Yes, via the screenly_cast_allowed_tags filter. The default set is small on
purpose, and links are reduced to their text because there is nothing to click on
a screen.

Which image is used?

The featured image if the post has one. Failing that, the first image in the post
content that comes from your media library, so adding a picture with the “Add
Media” button is enough, and you do not have to set a featured image as well.
Images hotlinked from other sites are ignored.

On an image’s own media URL, that image is the subject of the render.

Can I hide the date?

Yes:

add_filter( 'screenly_cast_show_date', '__return_false' );

The line above the title then shows your site name instead, so the render still
says where it came from.

Can I change the colors and typography?

The design is built on CSS custom properties, so overriding a handful of them is
usually enough. Add your own stylesheet after ours by attaching it to the
screenly-cast handle:

add_action( 'wp_enqueue_scripts', function () {
  wp_add_inline_style( 'screenly-cast', ':root{--color-ground:#101820;}' );
}, 100 );

The tokens worth knowing are --color-ground, --color-ink,
–color-ink-soft, --color-ink-dim and --color-brand, plus --root-min,
–root-gain and --root-max, which together drive the whole type scale.

Over a photograph there are two more: --srly-ground-deep-rgb, the scrim color
written as R G B channels, and --srly-text-shadow.

Why does my image media page work here but redirect normally?

Since WordPress 6.4, attachment pages are disabled by default and redirect to the
image file itself. This plugin keeps them renderable for signage requests only,
so casting a media URL still works without re-enabling attachment pages for
ordinary visitors.

Does it scroll long content automatically?

No, by design. On a large, non-interactive display, fixed unmoving content reads
better than anything that moves.