SVG Communicating Widgets

Transcription

1 SVG Communicating Widgets Jean-Claude Dufourd, Jean Le Feuvre et Cyril Concolato Department of Signal and Image Processing Télécom ParisTech page 1 J.C. Dufourd SVG Open '09

2 Examples of widgets and widget UAs Apple Dashboard Google Gadgets Microsoft Gadgets Yahoo! Connected TV Widgets Opera Widgets page 1 J.C. Dufourd SVG Open '09

3 SVG in Widgets and Widget UAs W3C Widgets P&C and A&E Will use DigSig later Large parts of Widget UA unspecified Aspect, behaviour, flexibility WUA easy to implement in SVG + script One for mobile One for itv page 3 J.C. Dufourd SVG Open '09

4 WUA Architecture Specific to this WUA Generic to all WUA SVG: presentation of the UI ES: business logic of the WUA ES: generic Widget UA code GPAC (C/C++): - SVG engine - ES engine - UPnP engine UI is designed in SVG WUA logic is implemented in ES GPAC Specific APIs A layer of C isolates Widget ES from WUA ES In a sense, this is a WUA design environment page 4 J.C. Dufourd SVG Open '09

5 WUA: Managing Widgets Install or discover widgets? Install each widget All from a directory ( service Announced on network (UPnP, web Present available widgets List of icons, home page, dock Present running widgets One at a time More ( resize Allow user layout / manipulation (move, J.C. Dufourd SVG Open '09

6 WUA: Widget Features Preferences / Execution State Save / Restore <preference> element or.preference attribute Can Widgets have a live, synced icon? Allowed by sharing the scene Widgets in a choice of formats WUA chooses which version it can render Transfer a Widget across Devices WUA is a UPnP service, discoverable by other WUAs J.C. Dufourd SVG Open '09

7 WUA Features: Last But Not Least Widget talking to a service UPnP / DLNA services in the home environment Widget talking to other widgets transparently See other widgets as plain (UpnP) services Widget Modularity In particular for adaptation page 7 J.C. Dufourd SVG Open '09

8 Widgets Communication Abstract communication model: ( out Messages with arguments (in / Sets of messages are interfaces Declaration in the widget manifest Message arguments are connected to scene attributes or events or script functions Messages are triggered by scene interaction or scripting J.C. Dufourd SVG Open '09

9 Binding Interface binding by the WUA ( UPnP Binding by type (URN in Messages and arguments have to match if present Messages and arguments can be ignored Widgets have limited information about what is connected to an interface: other widget? UPnP service? Independence from network addresses Independence from executing device page 9 J.C. Dufourd SVG Open '09

10 Declarations <content src="distvotemain.svg"> <cw:interfaces> <cw:interface type="urn:tpt:svc:communicationtest:1"> <cw:messageout name="switch"> <cw:output name="newtargetvalue" scriptparamtype="string"/> </cw:messageout> </cw:interface> </cw:interfaces> </content> <content src="comwidin.svg"> <cw:interfaces> <cw:interface type="urn:tpt:svc:communicationtest:1" serviceprovider="true"> <cw:messagein name="switch" outputtrigger="status.boolean"> <cw:input name="newtargetvalue" setattribute="set_status.bool"/> <cw:output name="status" attributemodified="status.boolean"/> </cw:messagein> </cw:interface> </cw:interfaces> </content> page 10 J.C. Dufourd SVG Open '09

11 Widget Modularity Modular Widget == multiple widgets designed to work together Messaging/voting widget connected to TV channel Broadcast with channel Display on TV Interaction components, one of which is activated: - One for touchscreen mobile - One for full-keyboard mobile - One for remote control page 11 J.C. Dufourd SVG Open '09

12 Implementation and Demo GPAC open source multimedia framework Fastest open source SVGT1.2 implementation Three Widget UAs Demo: iphone-style WUA Communicating widgets (within a WUA or between 2 ( machine WUAs on same Widget migration page 12 J.C. Dufourd SVG Open '09

13 Conclusion WUA design environment Uses SVGT1.2 for presentation Communication/component extensions Will work with any discovery protocol Location of services is transparent Improved security One-to-many, many-to-one and many-to-many connections Move widgets across devices: TV, PC, mobile Potential for convergence of TV, mobile and Internet Split widgets into collaborating parts Asynchronous connection and disconnection Works on small devices without script engine page 13 J.C. Dufourd SVG Open '09