It does not make sense to accumulate fractional error in non-capture mode
as you know exactly where the cursor is supposed to be, at least on Wayland.
On Wayland, we base movements on the current guest position and desired
target position, and the accumulated errors only skew our movements.
Build failed with _FORTIFY_SOURCE enabled because the compiler couldn't
ensure the switch statements didn't hit the default arm and thus wouldn't
define the variables. Adding a statically failing assert makes sure that
all code paths either define the variables or fail early.
$ cd client
$ env CFLAGS='-O1 -D_FORTIFY_SOURCE=1' cmake -B build/
$ make -C build
[...]
client/renderers/EGL/egl.c: In function ‘egl_calc_mouse_size’:
client/renderers/EGL/egl.c:299:36: error: ‘h’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
299 | (this->mouseHeight * (1.0f / h)) * this->scaleY
| ~~~~~~^~~~
When using the meta resize feautre the cursor is over the client window,
and as such the application continues to receive motion events. This
causes the window size to spaz out.
If the guest has it's output rotated (ie, landscape) we must rotate and
translate the pointer draw location, as well as all the translations of
cursor coordinate spaces based on the rotation, along with any local
rotations that may also be applied.
Unless the corresponding mouse down event was on our surface, we should
not be receiving the mouse up.
This is always the case on Wayland. On some other platforms,
SDL_CaptureMouse can be used to obtain input that happens outside the
Looking Glass surface, but Looking Glass does not make use of that
function.
We may want to process a mouse up if the corresponding mouse down
initiated a drag (e.g., of a window) that was released slightly outside
of the Looking Glass surface. Previously, Looking Glass would ignore the
mouse up, and the guest would be confused into thinking the button had
never been released, not ending the drag.
We are actually getting mouse events directly from Wayland instead of going
through SDL, so we call app_updateCursorPos in pointer motion handlers and
swallow the SDL event.
Also removed parameters for app_handleMouseBasic as it relies exclusively on
absolute positions provided by app_updateCursorPos. Wayland does not give
you relative movements at all unless grabbed and passing absolute movements
is semantically incorrect.
Note that when the cursor is grabbed, movements are handled entirely through
relativePointerMotionHandler in wayland.c and does not go through
app_handleMouseBasic at all.
If the guest cursor state & position is unknown we can not rely on the
information to detect edge crossings. As such only allow cursor input if
LG is operating in capture mode.
