filter: duplicate the code for the Lenovo x230 accel method

This is "once-tested, don't touch it again" code. The quirks on the touchpad
means we'd have to find that specific device again and re-test everything if
we change anything elsewhere in the code. So duplicate it properly, so that we
don't have to touch it again.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Jonas Ådahl <jadahl@gmail.com>

diff --git a/src/filter.c b/src/filter.c
index 369d7370ffabfdc52c4aade98ccb0085088acc1b..0c3e1de249795e712886f586cff9840053149bf4 100644 (file)
--- a/src/filter.c
+++ b/src/filter.c
@@ -96,6 +96,11 @@ filter_get_speed(struct motion_filter *filter)
 #define DEFAULT_ACCELERATION 2.0               /* unitless factor */
 #define DEFAULT_INCLINE 1.1                    /* unitless factor */
 
+/* for the Lenovo x230 custom accel. do not touch */
+#define X230_THRESHOLD v_ms2us(0.4)            /* in units/us */
+#define X230_ACCELERATION 2.0                  /* unitless factor */
+#define X230_INCLINE 1.1                       /* unitless factor */
+
 /*
  * Pointer acceleration filter constants
  */
@@ -337,6 +342,32 @@ accelerator_filter_low_dpi(struct motion_filter *filter,
        return accelerated;
 }
 
+static struct normalized_coords
+accelerator_filter_x230(struct motion_filter *filter,
+                       const struct normalized_coords *unaccelerated,
+                       void *data, uint64_t time)
+{
+       struct pointer_accelerator *accel =
+               (struct pointer_accelerator *) filter;
+       double accel_factor; /* unitless factor */
+       struct normalized_coords accelerated;
+       double velocity; /* units/us */
+
+       feed_trackers(accel, unaccelerated, time);
+       velocity = calculate_velocity(accel, time);
+       accel_factor = calculate_acceleration(accel,
+                                             data,
+                                             velocity,
+                                             accel->last_velocity,
+                                             time);
+       accel->last_velocity = velocity;
+
+       accelerated.x = accel_factor * unaccelerated->x;
+       accelerated.y = accel_factor * unaccelerated->y;
+
+       return accelerated;
+}
+
 static void
 accelerator_restart(struct motion_filter *filter,
                    void *data,
@@ -661,17 +692,39 @@ create_pointer_accelerator_filter_touchpad(int dpi)
        return &filter->base;
 }
 
+struct motion_filter_interface accelerator_interface_x230 = {
+       accelerator_filter_x230,
+       accelerator_restart,
+       accelerator_destroy,
+       accelerator_set_speed,
+};
+
+/* The Lenovo x230 has a bad touchpad. This accel method has been
+ * trial-and-error'd, any changes to it will require re-testing everything.
+ * Don't touch this.
+ */
 struct motion_filter *
 create_pointer_accelerator_filter_lenovo_x230(int dpi)
 {
        struct pointer_accelerator *filter;
 
-       filter = create_default_filter(dpi);
-       if (!filter)
+       filter = zalloc(sizeof *filter);
+       if (filter == NULL)
                return NULL;
 
-       filter->base.interface = &accelerator_interface;
+       filter->base.interface = &accelerator_interface_x230;
        filter->profile = touchpad_lenovo_x230_accel_profile;
+       filter->last_velocity = 0.0;
+
+       filter->trackers =
+               calloc(NUM_POINTER_TRACKERS, sizeof *filter->trackers);
+       filter->cur_tracker = 0;
+
+       filter->threshold = X230_THRESHOLD;
+       filter->accel = X230_ACCELERATION; /* unitless factor */
+       filter->incline = X230_INCLINE; /* incline of the acceleration function */
+
+       filter->dpi_factor = 1; /* unused for this accel method */
 
        return &filter->base;
 }