This is a change for how CSS is applied.
Previously, subelements (I'll take GtkEntry icons as an example) were
treated as having the same parent as the regular elements. So a selector
such as
.entry
would match an entry inside a window. But it'd also match the icon image
inside the entry. So CSS like
.entry { padding: 10px; }
would add 10px of padding to both the entry itself and to the icon image
inside the entry, so the icon would effective have 20px padding. To get
around that, one would have to unset it again like so:
.entry { padding: 10px; }
.entry.image { padding: unset; }
This is getting more and more of a problem as we make subelements
respect more properties that aren't inherited by default anyway, like
backgrounds and padding/margin/border.
This patch has one caveat though: It makes calling
gtk_style_context_save() the first time have an important side effect.
It's important to audit code to make sure it is only used for
subelements.
And last but not least, this patch is only useful if code unsets
parent's style classes that it doesn't want to apply any longer. Because
style classes are inherited by default (and I don't think we want to
change that), the example will still apply until the subelements no
longer contain the .entry style class.
If the menubar has an app-menu popover, and it is shown at the time of
disposing the window, it will attempt to transfer focus back to the
previous focus widget when undoing modality, even though the dispose()
code already did set_focus(NULL) previously.
At the time the popover is removed, there aren't many hints as to whether
the toplevel or the focus widget are being destroyed (ie. not still under
in_destruction), so just swap the order of these two calls.
For every other popover, this would all happen within dispose/destroy,
which is handled better.
This way we don't have to clear/refill the model every time but can keep
the existing model and only update the values.
A nice side benefit is that running an update keeps the current selection.
Its not really reasonable to handle failures to make_current, it
basically only happens if you pass invalid arguments to it, and
thats not something we trap on similar things on the X drawing side.
If GL is not supported that should be handled by the context creation
failing, and anything going wrong after that is essentially a critical
(or an async X error).
We make user facing gl contexts not attached to a surface if possible,
or attached to dummy surfaces. This means nothing can accidentally
read/write to the toplevel back buffer.
This adds the new type GdkGLContext that wraps an OpenGL context for a
particular native window. It also adds support for the gdk paint
machinery to use OpenGL to draw everything. As soon as anyone creates
a GL context for a native window we create a "paint context" for that
GdkWindow and switch to using GL for painting it.
This commit contains only an implementation for X11 (using GLX).
The way painting works is that all client gl contexts draw into
offscreen buffers rather than directly to the back buffer, and the
way something gets onto the window is by using gdk_cairo_draw_from_gl()
to draw part of that buffer onto the draw cairo context.
As a fallback (if we're doing redirected drawing or some effect like a
cairo_push_group()) we read back the gl buffer into memory and composite
using cairo. This means that GL rendering works in all cases, including
rendering to a PDF. However, this is not particularly fast.
In the *typical* case, where we're drawing directly to the window in
the regular paint loop we hit the fast path. The fast path uses opengl
to draw the buffer to the window back buffer, either by blitting or
texturing. Then we track the region that was drawn, and when the draw
ends we paint the normal cairo surface to the window (using
texture-from-pixmap in the X11 case, or texture from cairo image
otherwise) in the regions where there is no gl painted.
There are some complexities wrt layering of gl and cairo areas though:
* We track via gdk_window_mark_paint_from_clip() whenever gtk is
painting over a region we previously rendered with opengl
(flushed_region). This area (needs_blend_region) is blended
rather than copied at the end of the frame.
* If we're drawing a gl texture with alpha we first copy the current
cairo_surface inside the target region to the back buffer before
we blend over it.
These two operations allow us full stacking of transparent gl and cairo
regions.
This is a new function that gets called every time we're drawing
some area in the Gtk paint machinery. It is a no-op right now, but
it will be required later to keep track of what areas which
we previously rendered with GL was overwritten with cairo contents.
