Skinning

Overview

Skinning refers broadly to the ability to customize the Viewer user interface. The Skinning project is part of the User Interface Roadmap and specifically describes a path to make the Second Life user interface entirely data driven and customizable by Linden Lab, 3rd party developers, and individuals, without requiring changes to the primary application source code, and maintainable across updates.

Priority

See User Interface Roadmap

Objectives

Enable internal designers to more easily customize the look of Second Life
Enable external developers and residents to better serve their audiences, and save customizations and prepare skin "packages" that persist across viewer updates
- "Skinning" can mean a lot of things. So for this project, skinning shall initially mean:
1. A custom look using the same-sized images. (for example, Dazzle)
2. Custom floaters that display HTML and can speak back to the client through SLURLS.
3. Customizations or language customizations are retained across installs
4. "Simpler" skins that allow parts of the UI to be removed
5. Customized help links
Please use the 'discussion' page to raise constructive architecture considerations if you like.

Tasks

Phase 0

The first phase is to implement Project Dazzle, which is a first skin implementation and proof-of-needed-abstraction for changing the colors/look of the user interface.
Immediate priority to:
- VWR-5059 Include the ability to change skins and restore the Classic skin

Phase 1 - Widget Cleanup

VWR-6027 Skinning Phase 1

Objectives:
- Make all widget constructors parameterized
- Separate widget contents from layout
- Remove hard coded art and layout
- Additional UI cleanup
- All XUI-specific logic should happen in postBuild() call
- VWR-1884 Remove hard coded art and colors:
  - Remove programmatic art with attributes, e.g. volume sliders
  - Remove any backgrounds from icons, etc (use alpha)
  - Ensure that all images can be cropped and scaled
  - Allow specification of fixed size borders (i.e. so that button graphics with narrow boarders scale correctly)
  - Enable additional attributes to widgets for colors, etc
  - subtask: VWR-2447 Text drop-shadow settings aren't configurable in XML, resulting in legibility issues
  - All panel/floater layout should be data driven
  - Move All UI Settings to XML - Colors, other global UI settings
  - Eliminate the unused (legacy) xml files in \xui\en-us
  - Make all existing floaters use LLUICtrlFactory properly

Phase 2 - Switchable Skins

Objectives:
- Allow switching of skins without restarting the client
- Make it easier to see the effects of XUI edits
  - eg., Changing the language setting will reload all UI elements
- VWR-1885 Dynamic Reloading of UI elements (Hot swapping):
  - Color definitions
  - LLUIImage should be able to swap texture assets on the fly
  - Allow reloading of XUI file for live floaters and panels, including the menus and overlay bar
  - VWR-1883 Move different texture types into appropriate sub folders (OI Precache, etc) and use plaintext names
  - Ensure all floaters can handle missing UI elements and will behave reasonably or refuse to open with an appropriate message

Phase 3 - XML Widget Layout

Objectives:
- XUI Templates - Make all widet defaults data driven, allow additional templates for common widget subtypes
  - Put widget default values in XML
  - Put widget layout data in XML
- VWR-1882 Sparse XUI files
  - Make the XUI files less verbose and more readable
  - Only include non default values in XUI files
  - Remove all default values from the code (XML cleanup)
  - Create a tool to process all existing XML files and write out only the non-default values
  - Clean up the XML output at the same time
- Automatically Save Floater Positions and Sizes
  - Include minimized position (not currently saved)
- Document the UI XML format

Phase 4 - a "Simple UI" Skin

Objective: Enable a simplified interface for SL, as a custom skin to be packaged with the Viewer
- Make Advanced menus data driven
- Data Driven callbacks - UI Callbacks
  - Enable all menu items and overlay buttons to be entirely data driven
- VWR-1886 Other simplification tasks TBD, such as:
  - Allow buttons to open floaters by name
  - Include support for opening a specific tab
  - Differentiate between toggling state of singletons, showing/focusing, and opening new instances
  - Allow menus to be expanded/collapsed for simple vs. advanced usage
    - Specify layout of overlay bar and menu bar in "viewer.xml"
    - Allow multiple "overlay bars" to be added so that side bars or corner panels with buttons can be added

Future Phases

I18N

Objectives:
- Complete Internationalization of the SL Viewer
- Include translations of server messages from a downloadable XML file on login

Skin Packaging

VWR-7078 Enable Packaging and Resident customizations

Objectives:
- Facilitate packaging and distribution of skins
- enable external developers and residents to preserve changes across updates and distribute custom UI layouts
- Consider web based distribution / download of skins, enabling "live" updates
- Specify files that modify only (translations) or override completely (user customizations)
- Automated changelist generator for all releases
  - Also useful for mass translation (e.g. "Second Life") and rough first pass translations
- Allow residents to package changes and easily distribute them for easy installation by other users
  - enhance options in Edit > Preferences > Skins
    - a) Add dropdown option to preferences
    - b) Fill options from an XML file
  - add support for reading skins from zip file
  - investigate skin installer for all platforms

Customization Support

Objective: Clean up XUI and simplify further Skinning development
- Automatically Save Floater Positions and Sizes - Eliminate need to explicitly list rect controls for floaters
  - Create layout.xml, store default in app/skins, custom values in user/skins
  - Include minimized position (not currently saved)
- XUI Documentation - Document the UI XML format
  - improve documentation at Skinning HowTo/Basics
- Consistent Widget Interfaces - Make all widget interfaces consistent, access widgets only through interfaces

Dynamic Layout

VWR-1887 Improve the widget layout language and add auto sizing
- Objective: make it easier to change the XUI layout data
  - Choose a standard model for the layout language (e.g. CSS? qt-like?)
  - Allow elements to be grouped for layout purposes
  - Auto layout elements when no layout information is provided

Data Driven UI

Make the entire UI data driven; only control flow logic should remain as code

Other Specific Requests

Make iconic panels (i.e.. build tools) generally available
- Combination of fully iconic buttons and the ability for a button to open a specific tab in a floater
Docking / Hosting - Make the 3D window a layout element and allow floaters to be docked
- Possibly allow floaters to exist outside application window