Wayland/X Compositor Architecture By Example: Enlightenment DR19 - - PowerPoint PPT Presentation
Wayland/X Compositor Architecture By Example: Enlightenment DR19 Blog: http://e19releasemanager.wordpress.com Contact: zmike@enlightenment.org E19 Release Date: LOL Source: http://git.enlightenment.org/core/enlightenment.git/
– “The combining of visual elements from separate
– Geometry (size, position) – Visibility
– Geometry requests – Drag-n-drop
– Receives/retrieves application window data
– This is where “effects” come from
– Geometry, requests, visuals
– Input can be grabbed – Visuals can be retrieved
– Compositor must manually fetch/query pixel data – Compositor only receives updates when regions
– Compositor must fetch all data
– Resizing – Showing/Hiding
– Compositor must “know” when to
– Requires protocol transmission – Introduces latency
– All Window Managers are Compositing Window
– Special mechanism for requesting screenshots – Input handled by WM only
– Not required, however
– Compositor receives pixel data – Compositor is notified of pixmap
– No display server in between
– Occurs for entire frames – No tearing!
– Effects: fading, shadows – Some general issues
– Unable to use compositor canvas for drawing – All objects required X window to be shown
– Fade in/out effects
– Serious slowdowns during startup due to buggy
– Compositing not universally used across user
– Makes troubleshooting + bug fixing easier
– Gadget resizing no longer an issue
– Gadgets, borders, menus all drawn to compositor
– Greatly reduced compositing overhead – Improved accuracy
– Desk flip animations now composited, smooth – Sparklebear!
– Shading windows no longer requires
– Switching virtual desktops no longer requires
– Mostly the same as E17
– Difficult to use/manipulate composited source
– All client management relies on having X window – X-less Wayland compositor required a separate
– Window Manager manages compositor object
– API stabilized (hopefully)
– Better abstractions for client pixmap management
– Standalone Wayland compositing since August
– Easier follow interactions – Small speed improvements / reduced latency in
– Much easier to write cool effects
– Wayland and X rendering use same API
– Desksanity! – Pager16!
– Not using compositor canvas as effectively – Lots of workarounds for separate windows
– Huge amounts of code changed – Lots of work still remaining
– Enchilada
– Also make using them easy + sensible
– Better effects