On 17 April 2015 at 14:37, Hans de Goede <hdego...@redhat.com> wrote: > Hi, > > > On 17-04-15 13:17, Michal Suchanek wrote: >> >> On 17 April 2015 at 12:52, Hans de Goede <hdego...@redhat.com> wrote: >>> >>> Hi, >>> >>> >>> On 17-04-15 11:47, Michal Suchanek wrote: >>>> >>>> >>>> On 17 April 2015 at 09:11, Pekka Paalanen <ppaala...@gmail.com> wrote: >>>>> >>>>> >>>>> On Fri, 17 Apr 2015 13:43:11 +0900 >>>>> x414e54 <x414...@linux.com> wrote: >>>>> >>>>>> Thank you for the comments. >>>>>> I do have a few counterpoints but I will leave after that. >>>>>> >>>>>>> >>>>>>> Not sure an IR/laser/wii mote pointer should even be considered a >>>>>>> "relative" pointer since they operate in absolute coordinates. Given >>>>>>> this, there is no "set position" hint to consider. Transmitting >>>>>>> acceleramoter data via a "relative pointer" doesn't sound reasonable. >>>>>>> >>>>>> >>>>>> I think this is the issue right here. Pointers are not relative, mice >>>>>> are not pointers. >>>>> >>>>> >>>>> >>>>> What definition of a "pointer" are you using? >>>>> >>>>> The definition Wayland uses for a wl_pointer is a device that: >>>>> - requires a cursor image on screen to be usable >>>>> - the physical input is relative, not absolute >>>>> >>>>> This definition is inspired by mice, and mice have been called pointer >>>>> devices, so we picked the well-known name "pointer" for mice-like >>>>> devices. >>>>> >>>>> Specifically, a pointer is *not* a device where you directly point a >>>>> location on screen, like a touchscreen for example. For touchscreens, >>>>> there is a separate protocol wl_touch. >>>>> >>>>> For drawing tablets, there will be yet another procotol. >>>>> >>>>> Joysticks or gamepads fit into none of the above. For the rest of the >>>>> conversation, you should probably look up the long gamepad protocol >>>>> discussions from the wayland-devel mailing list archives. >>>> >>>> >>>> >>>> And how is a joystick different from a trackpoint, exactly? >>>> >>>> It uses different hardware interface and later different software >>>> interface but for no good reason. It's just 2 axis relative input >>>> device with buttons. Sure, the big joystick, gamepad directional cap >>>> and trackpoint are at a different place of the stick size scale and >>>> might have different hardware sensors which should be reflected with >>>> different acceleration settings but ultimately it's the same kind of >>>> device. >>> >>> >>> >>> Actually joystick analog inputs are absolute not relative. They give a >>> value >>> for exactly how much the "stick" has moved from the center. >>> >>> Except for dpads which are really buttons not relative axis, so joysticks >>> really are pretty much not like trackpoints in anyway. >>> >> >> Do you mean that the absolute trackpoint excentricity is somehow >> translated to relative motion delta in hardware so that it does look >> like a mouse although it is in fact a joystick? > > > Yes. > > Also have you ever used a trackpoint it is really nothing like a joystick, > with a joystick you move the stick and then it stays in position (there > are springs to center the stick when you let go, but you can remove those > and everything will still work just fine). > > Where as a trackpoint is more of a presure sensor which senses how much you > push against it in a certain direction, it does not actually move.
That's implementation detail. The input concept is the same. And yes, it might be hard to see the similarity between a full size joystick and a trackpoint. When you throw in all those GPIO mini joysticks and the gamepad directional joystick-like inputs and half size joysticks and arcade sticks you can see that there is a concept of stick input that scales to different sizes with different limitations. Thanks Michal _______________________________________________ wayland-devel mailing list wayland-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/wayland-devel