Okay, I've spent a whole day on this now, and it finally kinda works!
With this patch, CObject and all of its derived classes are reference
counted instead of tree-owned.
The previous, Qt-like model was nice and familiar, but ultimately also
outdated and difficult to reason about.
CObject-derived types should now be stored in RefPtr/NonnullRefPtr and
each class can be constructed using the forwarding construct() helper:
auto widget = GWidget::construct(parent_widget);
Note that construct() simply forwards all arguments to an existing
constructor. It is inserted into each class by the C_OBJECT macro,
see CObject.h to understand how that works.
CObject::delete_later() disappears in this patch, as there is no longer
a single logical owner of a CObject.
This macro goes at the top of every CObject-derived class like so:
class SomeClass : public CObject {
C_OBJECT(SomeClass)
public:
...
At the moment, all it does is create an override for the class_name() getter
but in the future this will be used to automatically insert member functions
into these classes.
This behavior and API was extremely counter-intuitive since our default
behavior was for applications to never exit after you close all of their
windows.
Now that we exit the event loop by default when the very last GWindow is
deleted, we don't have to worry about this.
Instead of LibGUI and WindowServer building their own copies of the drawing
and graphics code, let's it in a separate LibDraw library.
This avoids building the code twice, and will encourage better separation
of concerns. :^)
Currently the two available input types are:
- GMessageBox::InputType::OK (default)
- GMessageBox::InputType::OKCancel
Based on your choice, GMessageBox::exec() will return ExecOK or ExecCancel.
Eventually I'd like to do some kind of bitmap layers, and we definitely want
alpha channel support then, so let's just not paint ourselves into an
uncomfortable corner early on. :^)
Painter gains the ability to draw lines with arbitrary thickness.
It's basically implemented by drawing filled rects for thickness>1.
In PaintBrush, Tool classes can now override on_contextmenu() to
provide a context menu for the toolbox button. :^)
Put together a pretty well-performing queue using a Vector and an offset.
By using the new Vector::shift_left(int) instead of Vector::take_first()
we can avoid shifting the vector contents every time and instead only
do it every so often.
Maybe this could be generalized into a separate class, I'm not sure if it's
the best algorithm though, it's just what I came up with right now. :^)
I've used a SinglyLinkedList<Point> for the flood fill queue, since Vector
was death slow. This could definitely be made faster with a better algorithm
and/or data structure. :^)
