On 02/17/2016 05:39 PM, Peter Hutterer wrote:
> A nonzero resolution on the tilt axes is units/rad so we can calculate the
> physical min/max based. Uneven min/max ranges are supported.
>
> Signed-off-by: Peter Hutterer <peter.hutte...@who-t.net>
> ---
> src/evdev-tablet.c | 28 +++++++++++++++++++++-------
> test/tablet.c | 12 ++++++++----
> 2 files changed, 29 insertions(+), 11 deletions(-)
>
> diff --git a/src/evdev-tablet.c b/src/evdev-tablet.c
> index 1e5c2cd..226d5bd 100644
> --- a/src/evdev-tablet.c
> +++ b/src/evdev-tablet.c
> @@ -230,17 +230,31 @@ adjust_tilt(const struct input_absinfo *absinfo)
> double range = absinfo->maximum - absinfo->minimum;
> double value = (absinfo->value - absinfo->minimum) / range;
> const int WACOM_MAX_DEGREES = 64;
> + double max_degrees;
> +
> + /* If resolution is nonzero, it's in units/radian. But require
> + * a min/max less/greater than zero so we can assume 0 is the
> + * center */
> + if (absinfo->resolution != 0 &&
> + absinfo->maximum > 0 &&
> + absinfo->minimum < 0) {
> + int range_max = absinfo->value >= 0 ? absinfo->maximum
> + : -absinfo->minimum;
> +
> + max_degrees = 180.0/M_PI * range_max/absinfo->resolution;
> + } else {
> + /* Wacom supports physical [-64, 64] degrees, so map to that by
> + * default. If other tablets have a different physical range or
> + * nonzero physical offsets, they need extra treatment
> + * here.
> + */
> + max_degrees = WACOM_MAX_DEGREES;
> + }
>
> /* Map to the (-1, 1) range */
> value = (value * 2) - 1;
>
> - /* Wacom supports physical [-64, 64] degrees, so map to that by
> - * default. If other tablets have a different physical range or
> - * nonzero physical offsets, they need extra treatment
> - * here.
> - */
> -
> - return value * WACOM_MAX_DEGREES;
> + return value * max_degrees;
> }
This looks correct, if a bit difficult to follow because of the range
normalization (specifically the subtle need for "range_max"). You might
consider having the normalization only occur in the 'else' case so that
the 'if' can be written more straightforwardly:
double value;
const int WACOM_MAX_DEGREES = 64;
if ( /* can use resolution */ ) {
value = 180.0/M_PI * absinfo->value/absinfo->resolution;
} else {
/* normalize and scale to +-64 degrees */
}
return value;
That aside, everything looks fine.
Reviewed-by: Jason Gerecke <jason.gere...@wacom.com>
Jason
---
Now instead of four in the eights place /
you’ve got three, ‘Cause you added one /
(That is to say, eight) to the two, /
But you can’t take seven from three, /
So you look at the sixty-fours....
>
> static inline int32_t
> diff --git a/test/tablet.c b/test/tablet.c
> index c5dc892..ad6ac45 100644
> --- a/test/tablet.c
> +++ b/test/tablet.c
> @@ -3298,7 +3298,8 @@ START_TEST(tilt_x)
> ck_assert_double_ge(tx, -52);
>
> ty = libinput_event_tablet_tool_get_tilt_y(tev);
> - ck_assert_double_eq(ty, -64);
> + ck_assert_double_ge(ty, -65);
> + ck_assert_double_lt(ty, -63);
>
> libinput_event_destroy(event);
>
> @@ -3320,7 +3321,8 @@ START_TEST(tilt_x)
> ck_assert_double_le(tx, expected_tx + 2);
>
> ty = libinput_event_tablet_tool_get_tilt_y(tev);
> - ck_assert_double_eq(ty, -64);
> + ck_assert_double_ge(ty, -65);
> + ck_assert_double_lt(ty, -63);
>
> libinput_event_destroy(event);
>
> @@ -3365,7 +3367,8 @@ START_TEST(tilt_y)
> ck_assert_double_ge(ty, -52);
>
> tx = libinput_event_tablet_tool_get_tilt_x(tev);
> - ck_assert_double_eq(tx, -64);
> + ck_assert_double_ge(tx, -65);
> + ck_assert_double_lt(tx, -63);
>
> libinput_event_destroy(event);
>
> @@ -3387,7 +3390,8 @@ START_TEST(tilt_y)
> ck_assert_double_le(ty, expected_ty + 2);
>
> tx = libinput_event_tablet_tool_get_tilt_x(tev);
> - ck_assert_double_eq(tx, -64);
> + ck_assert_double_ge(tx, -65);
> + ck_assert_double_lt(tx, -63);
>
> libinput_event_destroy(event);
>
>
_______________________________________________
wayland-devel mailing list
wayland-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/wayland-devel
