didl toevoegingen

scribblings/media-renderer.scrbl

@@ -3,6 +3,7 @@
 @(require
   (for-label
    racket/base
+   (file "../media-file-server.rkt")
    (file "../media-renderer.rkt")))
 
 @title{Media Renderers}
@@ -80,10 +81,15 @@ included in the UPnP device description.
 
 Sets @racket[uri] as the current resource and starts playback.
 
+Supply DIDL-Lite in @racket[metadata].  Although AVTransport permits an empty
+string, some renderers do not enable seeking without resource metadata.  Use
+@racket[media-file-server-didl-lite] for resources published by this package.
+
 When @racket[next-uri] is supplied, it is installed with
 @tt{SetNextAVTransportURI} before playback starts.  A supporting renderer can
 open and buffer the next resource while the current resource is playing,
-allowing a gapless or near-gapless transition.
+allowing a gapless or near-gapless transition.  Supply matching DIDL-Lite in
+@racket[next-metadata].
 }
 
 @defproc[(media-renderer-play! [renderer media-renderer?]) any]{
@@ -107,7 +113,8 @@ Reports whether the renderer advertises the optional
 
 Sets the resource that follows the currently playing resource.  The action
 describes one next resource, not a complete queue.  After playback advances to
-that resource, call this function again to preload the following track.
+that resource, call this function again to preload the following track.  Use
+metadata that describes @racket[uri], not the current resource.
 }
 
 @defproc[(media-renderer-pause! [renderer media-renderer?]) any]