Pass everything needed for delayed evaluation for
`PlatformWindow::font_metrics()` to permit caching the font matching
result in the Text/TextInput's rendering cache.
We query text metrics frequently for text items, for example when in
layouts. This requires font resolution, which is about to become more
much more expensive due to analysis of the underlying text. To speed
this up, the objective is to use the item rendering cache. Making that
work in turn requires querying all related properties inside a property
tracker. That means we need to delay querying anything related to that,
including the font request needed for the `font_metrics()` function on
the PlatformWindow trait.
The component layout needs to be re-calculated. For some reason it is with
the Qt backend but not with GL.
Either way we can force it to re-calculate when the component changes.
It possibly doesn't get dirty when the dependencies are deleted.
Remove the intermediate properties for width and height and - just like
qt backend - apply the width and height in apply_window_properties
and when receiving a window resize event.
This also elimiates the get_geometry() getter as that would otherwise just
have been a FIXME'ed default().
* sixtyfps_timer_start needs to *take* the timer id out of the Rust
timer to avoid that the subsequent drop stops the timer again
* For the Qt event loop, call `timer_event()` once before entering
QCoreApplication::exec(), to schedule any timers that were started
beforehand.
* Added a way to quit the event loop gently, in order to use that
from the C++ unit test.
Similar to the window properties, use a property tracker with a change
handler in window to issue redraw requests. This allows eliminating the
forced repaints in the event loop after event processing and ensures
that the UI is repainted when programmatically setting a property, for
example.
Synchronize title/background/etc. once when the window is mapped and
afterwards lazily when the corresponding property tracker notifies us.
Since that callback can happen at any point in time and to also capture
potentially multiple changes, this first triggers a wakeup of the event
loop, when the actual application of properties happens.
By default PropertyTracker::evaluate() registers the currently
evaluating binding/tracker as a dependency. This should help with
repeaters and other scenarios where in the run-time we use property
trackers but want to track the overall "dirtyness" in the window with
regards to whether a redraw is needed or not.
The new evaluate_as_dependency_root() function allows skipping this
mechanism and is used for the two trackers in the window.
Since colorize property force the native item to be a ClippedImage, it had
a source rectangle, despite with and height defaulting to 0 and therefore
having an empty source rect would cause the scaling to not be right
Remove the pos parameter to the render functions and instead let
the item renderer apply the transformation on the rendere (femtovg
canvas or QPainter).
So `draw_*` functions in the backend now always operate in item local
coordinates.
Don't use the item's rendering cache to determine the image size, as
that's soley for rendering. The Qt backend doesn't use the item cache
and the GL backend neither after this change. Instead both backends have
a cache for decoded images.
This allows filling glyphs with gradients. However femtovg
appears to apply the start/end position per-glyph
instead of globally - resulting in a different result than Qt.
Add support for built-in property aliases and rename `color` to
`background` - in preparation for it also changing to type brush.
Right now the alias is silent, a deprecation and overall change
will come in a subsequent change.
When a tile is open artifacts would be visible around the edge of the
tile. That's because a zero width rectangle would cause pixels to appear
with femtovg. The Qt backend however has an early abort in
`get_geometry!`.
This patches applies the same early-abort semantics to both backends and
switches to `<= 0`, corresponding to euclid::Size's `is_empty()`.
