> On Fri, 25 Oct 2024, Lei Huang wrote:
> > Use a convergence factor to make the VM's input
> > global coordinates more closely approach the global
> > coordinates of DOM0.
>
> Dom0 is some Xen terminology. Do you mean "host" which is more often used
> in QEMU?
Yes, I will change it to host
>
> > Change-Id: I2c3f12f1fe7dfb9306d1fc40c4fd4d299937f4c6
> > Signed-off-by: Lei Huang <lei.hu...@amd.com>
> > ---
> > ui/sdl2.c | 32 ++++++++++++++++++++++++++++++--
> > 1 file changed, 30 insertions(+), 2 deletions(-)
> >
> > diff --git a/ui/sdl2.c b/ui/sdl2.c
> > index bd4f5a9da14..8f504dd8727 100644
> > --- a/ui/sdl2.c
> > +++ b/ui/sdl2.c
> > @@ -303,6 +303,34 @@ static void sdl_mouse_mode_change(Notifier *notify,
> > void *data)
> > }
> > }
> >
> > +/*
> > + *guest_x and guest_y represent the global coordinates on the VM side,
> > + *while x and y represent the global coordinates on the dom0 side.
> > + *The goal of this entire process is to align the global coordinates of
> > + *the VM with those of dom0 using dx and dy. The current approach aims
> > + *for precise calibration in once attempt; however, because guest_x
>
> "in one attempt" also add a space after the * at the beginning of lines.
okay, I will change it
>
> > + *and guest_y are non-zero values, they are not accurate values when
> > + *they are counted out to become negative.Therefore, achieving perfect
> > + *alignment in one attempt is impossible.Since the same calibration method
> > + *is used each time, repeated attempts cannot achieve alignment either.
> > + *By introducing a convergence factor, guest_x and guest_y can be made to
> > + *approach dom0's x and y indefinitely.
> > + *
> > + * QEMU (dx,dy) VM
> > + *calculates dx and dy using guest_x and guest_y ----> input driver
> > + * ^ |
> > + * | |
> > + * | V
> > + * | update
> > + * | guest_x,guest_y input dispatcher --->
> > WindowManager
> > + * | |
> > |
> > + * | |
> > |
> > + * | libdrm V
> > |
> > + * virtio-gpu <------ drmModeMoveCursor <------ compositor <-------
> > |
> > + * (guest_x,guest_y) calculates guest_x and
> > + * guest_y dy using dx and dy
> > + */
>
> What about other display devices than virtio-gpu? Does this work with
> those or do they need some update? If this is independent of graphics
> device maybe add a note that virtio-gpu is an example and could be any
> graphics device.
Yes,this applies to any device using SDL where the VM utilizes cursor plane
acceleration;
virtio-gpu is just an example. I will add it to the explanation.
>
> Regards,
> BALATON Zoltan
>
> > +#define CONVERGENCE_FACTOR 3
> > static void sdl_send_mouse_event(struct sdl2_console *scon, int dx, int dy,
> > int x, int y, int state)
> > {
> > @@ -331,8 +359,8 @@ static void sdl_send_mouse_event(struct sdl2_console
> > *scon, int dx, int dy,
> > y -= guest_y;
> > guest_x += x;
> > guest_y += y;
> > - dx = x;
> > - dy = y;
> > + dx = x / CONVERGENCE_FACTOR;
> > + dy = y / CONVERGENCE_FACTOR;
> > }
> > qemu_input_queue_rel(scon->dcl.con, INPUT_AXIS_X, dx);
> > qemu_input_queue_rel(scon->dcl.con, INPUT_AXIS_Y, dy);
> > --
> > 2.45.2
> >
> >
> >
>
>
