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Re: [MiNT] Wheel support in XaAES



Hello,

The below is how I imagine wheel-support can be done in XaAES and is already
implemented.

What a good news ! Great :)

However, I think that we need to find a decent value for WM_WHEEL,
it is 345 for now. Anyway, test this and let me know how it works.


                       XaAES and wheel mouse handling.

  This has changed a little compared to the original documentation and
implementation. When the wheel is on a window whose owner dont know about
 mouse wheels at all, normal WM_ARROWED messages are sent.

... but only if the window has the corresponding slider, right ?

There is no extra
 info added to these messages in this case, as it were in the original
 implementation.

I think it's not a pb. If one want to manage the wheel... then he just has to ask for wheel messages.

Currently mouse wheel events are sent to the owner of the window underneath
 the mouse pointer

Very good :)

in all cases except when owner of mouse_lock() is waiting
 for MU_WHEEL.

Well... i see 3 kind of applications:
- applications that don't support mouse wheel: they will receive standard WM_ARROWED messages only if the window has the corresponding slider. - applications that support WM_WHEEL messages: they will receive WM_WHEEL messages on mouse wheel click (msg[3] is the window under the mouse, even if the window doesn't have the corresponding slider) - applications that manage mouse wheel thru MU_WHEEL data. The main evnt_multi() loop has the MU_WHEEL bit set, but this application may perform some evnt_mesag() calls, or some evnt(MU_MESAG|MU_TIMER) calls and here, the message WM_WHEEL should not be sent (imo) !

The problem is for the 3rd kind of application. If the application is busy sending and receiving AES messages (GEMscript, VA-protocol...) and uses a second evnt_multi(MU_TIMER|MU_MESAG) loop for that purpose, in that case a mouse wheel click shall not be transformed to a WM_ARROWED message, nor to a WM_WHEEL message. This is an important point for me, because with the current design of mouse wheel in XaAES, all my softwares will be of the 3rd kind.

I propose a simple solution few lines later...

For programmers who want to take advantage of mouse wheels in a better way,
 here's an overview;

  wind_set(handle, WF_WHEEL, mode, wheel_mode, 0, 0);

handle Window handle, or 0 if one wants settings to apply to all windows
              opened hereafter by the application.
   mode        0 = Turn extended wheel awareness off, 1 = Turn on.
   wheel_mode
           XWHL_REALWHEEL ( 0 )
When wheel_mode is set to 0 (XWHL_REALWHEEL), XaAES will send
              real wheel messages, constructed as follows;

              msg[0] = WM_WHEEL ( 345 )
              msg[1] = ID of sender
              msg[2] = ...
              msg[3] = window handle
              msg[4] = orient
              msg[5] = wheel ID
              msg[6] = wheel amount
              msg[7] = Not used, always 0
               'orient' is a bitmask where bit 0 indicates direction, and
              bit 1 indicates orientation;

               bit 0  -  0 = up or left
                         1 = down or right
               bit 1  -  0 = vertical (bit 0 indicates UP/DOWN)
                         1 = horizontal (bit 0 indicates LEFT/RIGHT)

              'wheel ID' contains the wheel number. 0 is wheel #1, etc..
          'wheel amount' holds the number of wheel-turns.

I like this message... but an important information is missing: the position of the mouse pointer (x and y). Without this information, the message seems useless for me (anyway, it's far better than WM_ARROWED/WA_WHEEL (IMO)).

XWHL_AROWWHEEL ( 1 ) This is the default wheel_mode set if the value passed is outside the available range. When this mode is selected, normal WM_ARROWED messages are sent upon each wheel turn. With this mode, WM_ARROWED messages are send even when
              the window has no ARROW gadgets.

Good !


           XWHL_SLDRWHEEL ( 2 )
When wheel_mode is set to 2 (XHWL_SLDRWHEEL), XaAES converts
              wheel turns into slider movements. XaAES sends standard
              WM_VSLID/WM_HSLID messages reflecting the wheel turns.
For this to work, WF_VSLIDE/WF_HSLIDE wind_get/set() modes have been extended. When the application gets the WM_xSLIDE message,
              it must pass back the position from the message unmodified
              together with your modified position;

              wind_set(handle, WF_[V,H]SLIDE, postion, unmodified, 0, 0);

Even if the application snaps slider movements and finds that the slider does not move, it has to pass back the unmodified
              slider position via wind_set(). In cases where the original
slider position match the prevsiously set position, XaAES does not set or redraw the slider. But it needs to collect the 'real' position of the slider for wheel -> slider calculations to work.

I think i understand the reason of this mode. In most systems that support the wheel (i only tested mandrake and windows), a mouse wheel click is equivalent to 3 (it's an average) line up/left/dw/right messages. For example, in my xterm windom (under linux), the window content scroll by 3 lines per mouse wheel click.

the slider equivalent is a good idea, but the AES is not the right place for that (IMO). The right place for such stuff (transform mouse wheel click to movement of several lines) is a higher GEM library like cflib or windom. Furthermore, i don't think that this mode will made the programmer life easier. If a programmer want to transform a mouse wheel click to several lines movement, then the easier way is to catch WM_WHEEL message and call 3 times the internal function "move 1 line up/down" of the application.

BTW, there's a missing wheel_mode :

XWHL_MUWHEEL_ONLY, or XWHL_QUIET, or XWHL_NO_MSG to tell the AES that the application will call event_multi() with MU_WHEEL when he'd like to read mouse wheel events. The AES shall never transform mouse wheel click to message.

Last:
for the naming of the constant, i would vote for removing the first 'X' letter (WHL_REALWHEEL is ok, no need to prefix with a 'X')


best regards,
Arnaud.

PS: i'm very happy with the work done on the mouse wheel in XaAES... i hope my atari hardware will soon support the mouse wheel ;)