[Qemu-devel] Gentlemen we have absolute movement! was:Absolute USB-HID device musings (was Re: VNC Terminal Server)

[Brad Campbell <brad@wasp.net.au>]

Brad Campbell wrote:
> Lonnie Mendez wrote:
> 
>>   Please see the patch posted yesterday to this mailing list:
>>
>> http://gnome.dnsalias.net/patches/qemu-hidmousexp.patch
> 
> Ta for that.. not sure how I missed it.
> Now to try and get it to work..
> 

Ok.. 1st cut.. it's not great, and it's not hooked up to anything at the moment (the mouse just 
tootles around the screen on a timer) BUT! we have absolute movement.

The *stunning* news is it's resolution independent.. 640x480 - 800x600 - 1024x768
0,0 is top left and 7fff.7fff is bottom right.. no client scaling required..

Think I've figured out the Z axis thing also.. and we are good for relative movement on that still
(The Z axis below is way wrong, but I think I have figured it out)

static const uint8_t qemu_mouse_hid_report_descriptor[] = {
         0x05, 0x01, /* Usage Page Generic Desktop */
         0x09, 0x01, /* Usage Mouse */
         0xA1, 0x01, /* Collection Application */
         0x09, 0x01, /* Usage Pointer */
         0xA1, 0x00, /* Collection Physical */
         0x05, 0x09, /* Usage Page Button */
         0x19, 0x01, /* Usage Minimum Button 1 */
         0x29, 0x03, /* Usage Maximum Button 3 */
         0x15, 0x00, /* Logical Minimum 0 */
         0x25, 0x01, /* Logical Maximum 1 */
         0x95, 0x03, /* Report Count 3 */
         0x75, 0x01, /* Report Size 1 */
         0x81, 0x02, /* Input (Data, Var, Abs) */
         0x95, 0x01, /* Report Count 1 */
         0x75, 0x05, /* Report Size 5 */
         0x81, 0x01, /* Input (Cnst, Var, Abs) */
         0x05, 0x01, /* Usage Page Generic Desktop */
         0x09, 0x30, /* Usage X */
         0x09, 0x31, /* Usage Y */
         0x15, 0x00, /* Logical Minimum 0 */
         0x27, 0xFF, 0xFF, 0x00, 0x00, /* Logical Maximum 0xffff */
         0x75, 0x10, /* Report Size 32 */
         0x95, 0x02, /* Report Count 2 */
         0x81, 0x02, /* Input (Data, Var, Abs) */
//      0x09, 0x32, /* Usage Z */
//      0x15, 0x81, /* Logical Minimum -127 */
//      0x25, 0x7F, /* Logical Maximum 127 */
//      0x75, 0x08, /* Report Size 8 */
//      0x95, 0x01, /* Report Count 1 */
         0xC0,       /* End Collection */
         0xC0,       /* End Collection */
};
#endif

static int usb_mouse_poll(USBMouseState *s, uint8_t *buf, int len)
{
     int dx, dy, dz, b, l, aa, bb, cc, dd;

     dx = int_clamp(s->dx, -128, 127);
     dy = int_clamp(s->dy, -128, 127);
     dz = int_clamp(s->dz, -128, 127);

     s->dx -= dx;
     s->dy -= dy;
     s->dz -= dz;
     b = 0;
     if (s->buttons_state & MOUSE_EVENT_LBUTTON)
         b |= 0x01;
     if (s->buttons_state & MOUSE_EVENT_RBUTTON)
         b |= 0x02;
     if (s->buttons_state & MOUSE_EVENT_MBUTTON)
         b |= 0x04;

     buf[0] = b;
     buf[1] = s->X & 0xff;
     buf[2] = s->X >> 8;
     buf[3] = s->Y & 0xff;
     buf[4] = s->Y >> 8;
     aa=buf[1];
     bb=buf[2];
     cc=buf[3];
     dd=buf[4];
     l = 5;

     return l;
}

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