Previously, any frames in flight (`requestAnimationFrame`) on web were
not being cancelled (`cancelAnimationFrame`) when `WebRunner::destroy`
was called. If a user called `destroy`, then immediately removed the
canvas from the DOM, eframe could panic with a "failed to find (canvas)
element by id" error message.
This PR changes two things:
- The canvas element is directly referenced everywhere it's needed
instead of being looked up by `canvas_id`[^1]
- The RAF handle is stored in `WebRunner` and `cancelAnimationFrame` is
called on it inside of `WebRunner::destroy`[^2]
[^1]: The WebGL/WGPU backends were already holding onto the canvas (and
associated GPU context), so the change is just converting all the
`get_element_by_id` lookups to retrieve the canvas from the web runner
handle.
[^2]: There is only ever one frame in flight, so we store it directly as
a scalar field.
Update modifier state from web mouse events. This allows modifiers to be
correctly updated when the window is not in focus but the mouse is still
moving over the window.
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Closes <https://github.com/emilk/egui/issues/3474>.
* Using tracing-subscriber in hello_world example
* Add Key::Plus/Minus/Equals
* Warn if failing to guess OS from User-Agent
* Remove jitter when using Context::set_pixels_per_point
* Demo app: zoom in/out using ⌘+ and ⌘-
* Demo app: make backend panel GUI scale slider better
* Optimize debug builds a bit
* typo
* Update changelog
* Add helper module `egui::gui_zoom` for zooming an app
* Better names, and update changelog
* Combine Plus and Equals keys
* Last fix
* Fix docs