Keep both raw and action delta in move model

Accumulated values can be obtained either by using the raw_delta,
which is the actual (filtered) change between frames, or by using
the action delta, which sums up to the same position, but in a non-
linear fashion. Use the raw delta for pointer gestures.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>

7 files changed, 43 insertions, 30 deletions

diff --git a/src/gestures-combo.c b/src/gestures-combo.c
index 6ce6197..5b6de5b 100644
--- a/src/gestures-combo.c
+++ b/src/gestures-combo.c
@@ -61,10 +61,10 @@ int gru_combo(struct grail *ge,
         }
         if (!(move->active & fm_mask))
                 return 0;
-        prop[0] = move->fm[FM_X].delta;
-        prop[1] = move->fm[FM_Y].delta;
-        prop[2] = move->fm[FM_R].delta;
-        prop[3] = move->fm[FM_A].delta;
+        prop[0] = move->fm[FM_X].action_delta;
+        prop[1] = move->fm[FM_Y].action_delta;
+        prop[2] = move->fm[FM_R].action_delta;
+        prop[3] = move->fm[FM_A].action_delta;
         gru_event(ge, state->gid, move, prop, 4);
         return 1;
 }
diff --git a/src/gestures-pan.c b/src/gestures-pan.c
index b8e1751..c951b78 100644
--- a/src/gestures-pan.c
+++ b/src/gestures-pan.c
@@ -59,10 +59,15 @@ int gru_pan(struct grail *ge,
                 state->gid = gin_gid_begin(ge, type, PRIO_GESTURE, frame);
                 state->active = 1;
         }
-        if (!(move->active & fm_mask))
-                return 0;
-        prop[0] = move->fm[FM_X].delta;
-        prop[1] = move->fm[FM_Y].delta;
+        if (move->single) {
+                prop[0] = move->fm[FM_X].raw_delta;
+                prop[1] = move->fm[FM_Y].raw_delta;
+        } else {
+                if (!(move->active & fm_mask))
+                        return 0;
+                prop[0] = move->fm[FM_X].action_delta;
+                prop[1] = move->fm[FM_Y].action_delta;
+        }
         gru_event(ge, state->gid, move, prop, 2);
         return 1;
 }
diff --git a/src/gestures-pinch.c b/src/gestures-pinch.c
index 358718d..62f6601 100644
--- a/src/gestures-pinch.c
+++ b/src/gestures-pinch.c
@@ -61,7 +61,7 @@ int gru_pinch(struct grail *ge,
         }
         if (!(move->active & fm_mask))
                 return 0;
-        prop[0] = move->fm[FM_R].delta;
+        prop[0] = move->fm[FM_R].action_delta;
         gru_event(ge, state->gid, move, prop, 1);
         return 1;
 }
diff --git a/src/gestures-rotate.c b/src/gestures-rotate.c
index 5db4228..fa0db22 100644
--- a/src/gestures-rotate.c
+++ b/src/gestures-rotate.c
@@ -61,7 +61,7 @@ int gru_rotate(struct grail *ge,
         }
         if (!(move->active & fm_mask))
                 return 0;
-        prop[0] = move->fm[FM_A].delta;
+        prop[0] = move->fm[FM_A].action_delta;
         gru_event(ge, state->gid, move, prop, 1);
         return 1;
 }
diff --git a/src/gestures-tapping.c b/src/gestures-tapping.c
index 0f9b215..ab86c0f 100644
--- a/src/gestures-tapping.c
+++ b/src/gestures-tapping.c
@@ -86,7 +86,7 @@ int gru_tapping(struct grail *ge,
                 return 0;
         prop[0] = move->time - state->start;
         gin_gid_event(ge, state->gid,
-                      move->fm[FM_X].val, move->fm[FM_Y].val, state->ntouch,
+                      move->fm[FM_X].value, move->fm[FM_Y].value, state->ntouch,
                       prop, 1, 1);
         state->status = TAP_BEGIN;
         state->ntouch = 0;
diff --git a/src/grail-gestures.c b/src/grail-gestures.c
index 3daeaec..eda1d38 100644
--- a/src/grail-gestures.c
+++ b/src/grail-gestures.c
@@ -83,23 +83,25 @@ static float compute_rotation(float x, float y, float r,
         return da;
 }
 
+/* Response-augmented EWMA filter, courtesy of Vojtech Pavlik */
 static float move_filter(const struct filter_model *m, float val)
 {
-        if (val > m->val - m->fuzz / 2 && val < m->val + m->fuzz / 2)
-                return m->val;
-        if (val > m->val - m->fuzz && val < m->val + m->fuzz)
-                return (m->val * 3 + val) / 4;
-        if (val > m->val - m->fuzz * 2 && val < m->val + m->fuzz * 2)
-                return (m->val + val) / 2;
+        if (val > m->value - m->fuzz / 2 && val < m->value + m->fuzz / 2)
+                return m->value;
+        if (val > m->value - m->fuzz && val < m->value + m->fuzz)
+                return (m->value * 3 + val) / 4;
+        if (val > m->value - m->fuzz * 2 && val < m->value + m->fuzz * 2)
+                return (m->value + val) / 2;
         return val;
 }
 
 static void move_reset(struct move_model *m, int i, float val)
 {
         struct filter_model *fm = &m->fm[i];
-        fm->delta = 0;
-        fm->val = val;
-        fm->orig = val;
+        fm->raw_delta = 0;
+        fm->action_delta = 0;
+        fm->value = val;
+        fm->original = val;
         m->tickle &= ~(1 << i);
         m->active &= ~(1 << i);
 }
@@ -107,19 +109,20 @@ static void move_reset(struct move_model *m, int i, float val)
 static void move_update(struct move_model *m, int i, float val)
 {
         struct filter_model *fm = &m->fm[i];
-        fm->delta = val - fm->val;
-        fm->val = val;
-        if (fabs(fm->delta) > 0.5)
+        fm->raw_delta = val - fm->value;
+        fm->action_delta = fm->raw_delta;
+        fm->value = val;
+        if (fabs(fm->raw_delta) > 0.5)
                 m->tickle |= (1 << i);
         else
                 m->tickle &= ~(1 << i);
         if (m->active & (1 << i))
                 return;
-        fm->delta = val - fm->orig;
-        if (fabs(fm->delta) > fm->bar)
+        fm->action_delta = val - fm->original;
+        if (fabs(fm->action_delta) > fm->bar)
                 m->active |= (1 << i);
         else
-                fm->delta = 0;
+                fm->action_delta = 0;
 }
 
 void gru_init_motion(struct grail *ge)
@@ -170,7 +173,7 @@ void gru_motion(struct grail *ge,
                 y = move_filter(&m->fm[FM_Y], y);
                 r = compute_radius(x, y, frame);
                 r = move_filter(&m->fm[FM_R], r);
-                a = m->fm[FM_A].val;
+                a = m->fm[FM_A].value;
                 a += compute_rotation(x, y, r, &gru->frame, frame);
                 a = move_filter(&m->fm[FM_A], a);
                 move_update(m, FM_X, x);
@@ -188,12 +191,12 @@ void gru_event(struct grail *ge, int gid,
                const struct move_model *m,
                const grail_prop_t *prop, int nprop)
 {
-        gin_gid_event(ge, gid, m->fm[FM_X].val, m->fm[FM_Y].val, m->ntouch,
+        gin_gid_event(ge, gid, m->fm[FM_X].value, m->fm[FM_Y].value, m->ntouch,
                       prop, nprop, 0);
 }
 
 void gru_end(struct grail *ge, int gid, const struct move_model *m)
 {
-        gin_gid_end(ge, gid, m->fm[FM_X].val, m->fm[FM_Y].val, m->ntouch);
+        gin_gid_end(ge, gid, m->fm[FM_X].value, m->fm[FM_Y].value, m->ntouch);
 }
 
diff --git a/src/grail-gestures.h b/src/grail-gestures.h
index 3ace580..2acbb6d 100644
--- a/src/grail-gestures.h
+++ b/src/grail-gestures.h
@@ -37,7 +37,12 @@
 #define FM_A            3
 
 struct filter_model {
-        float delta, val, orig, fuzz, bar;
+        float raw_delta;
+        float action_delta;
+        float value;
+        float original;
+        float fuzz;
+        float bar;
 };
 
 struct move_model {