[sane-devel] SANE 1.1.0 Release discussion

[m. allan noah]

On Fri, May 16, 2008 at 2:13 PM, m. allan noah <kitno455 at gmail.com> wrote:
> On Fri, May 16, 2008 at 12:21 PM, m. allan noah <kitno455 at gmail.com> wrote:
>
>> 5. One new SANE_TYPE value: HW_BUTTON
>
> actually, as i am trying to implement this- i notice that the
> constraint is not really enough info to distinguish between types, as
> the RANGE and WORD_LIST are applicable to INT and FIXED types. we
> really need to keep the existing SANE_TYPE value on buttons. so, i am
> going to suggest a change to use a capability bit instead:
> SANE_CAP_HW_BUTTON
>
> It becomes hard to interpret all the possible combinations of
> SANE_CAP, but we may be able to provide some guidance in the standard.

And, after yet more digging, it appears that SANE_CAP_HARD_SELECT is
already providing just what we need, with the fujitsu and plustek
backends using it for buttons, and the hp3900 backend using it for
some read-only values that would be better handled with just
SANE_CAP_SOFT_SELECT. No other backends use it. We can clarify the
textual description in the standard to indicate that front-ends should
poll for changes in value.

allan
-- 
"The truth is an offense, but not a sin"