[PATCH v2 weston] libinput-device: use the discrete axis value for wheel events

[Jonas Ådahl]

On Thu, Jan 15, 2015 at 01:14:43PM +1000, Peter Hutterer wrote:
> libinput < 0.8 sent wheel click events with value 10. Since 0.8
> the value is the angle of the click in degrees but it now provides
> the click count as separate value. To keep backwards-compat with
> existing clients, we just send multiples of the click count.
> 
> Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
> ---

This one is now pushed as well, with a fix (normalize_scroll should
return a double) amended into it.


Thanks

>  src/libinput-device.c | 44 ++++++++++++++++++++++++++++++++++++++++----
>  1 file changed, 40 insertions(+), 4 deletions(-)
> 
> diff --git a/src/libinput-device.c b/src/libinput-device.c
> index e68b54d..d10202a 100644
> --- a/src/libinput-device.c
> +++ b/src/libinput-device.c
> @@ -126,6 +126,44 @@ handle_pointer_button(struct libinput_device *libinput_device,
>  		      libinput_event_pointer_get_button_state(pointer_event));
>  }
>  
> +static int
> +normalize_scroll(struct libinput_event_pointer *pointer_event,
> +		 enum libinput_pointer_axis axis)
> +{
> +	static int warned;
> +	enum libinput_pointer_axis_source source;
> +	double value;
> +
> +	source = libinput_event_pointer_get_axis_source(pointer_event);
> +	/* libinput < 0.8 sent wheel click events with value 10. Since 0.8
> +	   the value is the angle of the click in degrees. To keep
> +	   backwards-compat with existing clients, we just send multiples of
> +	   the click count.
> +	 */
> +	switch (source) {
> +	case LIBINPUT_POINTER_AXIS_SOURCE_WHEEL:
> +		value = 10 * libinput_event_pointer_get_axis_value_discrete(
> +								   pointer_event,
> +								   axis);
> +		break;
> +	case LIBINPUT_POINTER_AXIS_SOURCE_FINGER:
> +	case LIBINPUT_POINTER_AXIS_SOURCE_CONTINUOUS:
> +		value = libinput_event_pointer_get_axis_value(pointer_event,
> +							      axis);
> +		break;
> +	default:
> +		value = 0;
> +		if (warned < 5) {
> +			weston_log("Unknown scroll source %d. Event discarded\n",
> +				   source);
> +			warned++;
> +		}
> +		break;
> +	}
> +
> +	return value;
> +}
> +
>  static void
>  handle_pointer_axis(struct libinput_device *libinput_device,
>  		    struct libinput_event_pointer *pointer_event)
> @@ -137,8 +175,7 @@ handle_pointer_axis(struct libinput_device *libinput_device,
>  
>  	axis = LIBINPUT_POINTER_AXIS_SCROLL_VERTICAL;
>  	if (libinput_event_pointer_has_axis(pointer_event, axis)) {
> -		value = libinput_event_pointer_get_axis_value(pointer_event,
> -							      axis);
> +		value = normalize_scroll(pointer_event, axis);
>  		notify_axis(device->seat,
>  			    libinput_event_pointer_get_time(pointer_event),
>  			    WL_POINTER_AXIS_VERTICAL_SCROLL,
> @@ -147,8 +184,7 @@ handle_pointer_axis(struct libinput_device *libinput_device,
>  
>  	axis = LIBINPUT_POINTER_AXIS_SCROLL_HORIZONTAL;
>  	if (libinput_event_pointer_has_axis(pointer_event, axis)) {
> -		value = libinput_event_pointer_get_axis_value(pointer_event,
> -							      axis);
> +		value = normalize_scroll(pointer_event, axis);
>  		notify_axis(device->seat,
>  			    libinput_event_pointer_get_time(pointer_event),
>  			    WL_POINTER_AXIS_HORIZONTAL_SCROLL,
> -- 
> 2.1.0
>