For pure-Rust connections, there is no XCB connection that can be passed into
the display constructor. Thus, this PR enables the display to be created without
needing an XCB or Xlib handle, by providing `None` in the constructor.
cc rust-windowing/raw-window-handle#120
Signed-off-by: John Nunley <dev@notgull.net>
This is based on the API that will be used for no-copy presentation. But
wraps it in `set_buffer`.
This also fixes the Wayland buffer code to set `self.width` and
`self.height` on resize, and set the length of the shared memory file
when the buffer is created.
Co-authored-by: jtnunley <jtnunley01@gmail.com>
A `Context` is created with a display handle, and a `Surface` is created
with a `&Context` and a window handle. Thus multiple windows can be
created from the same context without duplicating anything that can be
shared. This API is broadly similar to `wgpu` or `glutin`.
On Wayland, the `Context` contains the `EventQueue`, which is shared
between windows, and the `WlShm` global. On X11, `Context::new` checks
for the availability of XShm, and contains a bool representing that as
well as the `XCBConnection`. The shared context data is stored within
the window in an `Arc`.
On other platforms, the display isn't used and `Context` is empty. This
does however test that the display handle has the right type on those
platforms and fail otherwise. Previously the code didn't test that.
Closes https://github.com/rust-windowing/softbuffer/issues/37.
