Avoid creating an intermediate array of items to free the graphics resources.
Instead call run-time function with the item tree as a parameter, which is traversed.
It's practically the same data structure that was previously created, except
that it is shared/global and has little holes for the dynamic tree items, but those are easy to skip.
The font resolution function querying fontdb is fast now, so we can
always call it when rendering text. That way we don't need all the
indirection in the text_size(), etc. functions, we don't need an entry
in the item graphics cache for the font and we can avoid a lot of
property dependencies.
Unfortunately the text property was not included in the property dependency chain
for the cached Font.
This is fixed by delaying that with a getter function, but in the mid term
we should be able to remove this again once
femtovg learns lazy font resolution.
Set QStyle::State_Active conditional to whether the window is active,
which maps to Qt's active window concept and winit's has-focus (until we
render popups differently).
If the root item is a Window, then we use the default-font-* properties as the basis
for all unspecified font properties in text rendering.
This patch centralizes the code for retrieving that in the runtime window.
If this becomes a performance bottleneck, then we could cache it in a
box-pinned property in the run-time window.
since there is only one function in it, just put that function in the Window
then there is no need to heap alocate a dyn FontMetrics just to call this function.
In preparation of having mutiple-lines TextInput, we will need to give more
data to this function so it no longer belong in FontMetrics
Also remove the unused FontMetric::line_height()
That's all it is nowadays, it's a wrapper around Rc<Window>. It's not an
alias because we need to also "wrap" it to C++ via cbindgen, but that's
about it.
* Remove the `new` function from the main impl and use the slightly
less visible From conversion trait
* Make the inner Rc<Window> pub(crate) instead of pub
* Instead, provide a public as_any() accessor that the Qt backend can use
If we were to add `sixtyfps:🪟:Window` to the re_exports, then
this clashes. We might rename the former, but this is a cleaner naming
in any case.
Relates to #333
This requires the image size query to be window independent and go
through the backend instead.
This implies minor changes for the Qt backend and bigger ones for the GL
backend:
* There exists now a thread-local IMAGE_CACHE, which is used by the
backend's image_size() function as well as by the renderer for
loading CPU side images.
* The image remain as decoded images in there (including SVG tree)
and the window now has a texture_cache, which holds CachedImage
with ImageData::Texture.
* Rendering an image item therefore fetches the CPU side image,
calls upload_to_gpu() on it, which creates a new Rc<CachedImage>
and that's stored in the texture_cache.
* The texture cache continues to be pruned when hiding the window.
All implementations of the function return the actual source size in
pixels, disregarding the window scale factor. The function is called in
Image's layout_info() to return the image size as preferred size. Since
the logical length is the default length, there's no need to do any
scaling anyway.
We don't need a property reference anymore, a plain image reference is fine AFAICS.
Dirtyness of the source is tracked on the caller side of layouting_info()
or in the draw_image_impl anyway.
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().