3 files changed, 32 insertions, 22 deletions

diff --git a/src/gestures-pinch.c b/src/gestures-pinch.c
index 91e6504..d05b06f 100644
--- a/src/gestures-pinch.c
+++ b/src/gestures-pinch.c
@@ -39,34 +39,18 @@ static void set_props(struct combo_model *s,
                       const struct move_model *m,
                       const struct touch_frame *frame)
 {
-        float x1, y1, x2, y2, x, y;
-        int i;
+        struct grail_coord min, max;
         s->prop[GRAIL_PROP_PINCH_DR] = m->fm[FM_R].action_delta;
         s->prop[GRAIL_PROP_PINCH_VR] = m->fm[FM_R].velocity;
         s->prop[GRAIL_PROP_PINCH_R] = m->fm[FM_R].value;
         s->nprop = 3;
         if (!frame->nactive)
                 return;
-        x = frame->active[0]->prop[TP_POS_X];
-        y = frame->active[0]->prop[TP_POS_Y];
-        x1 = x2 = x;
-        y1 = y2 = y;
-        for (i = 1; i < frame->nactive; i++) {
-                x = frame->active[i]->prop[TP_POS_X];
-                y = frame->active[i]->prop[TP_POS_Y];
-                if (x < x1)
-                        x1 = x;
-                if (y < y1)
-                        y1 = y;
-                if (x > x2)
-                        x2 = x;
-                if (y > y2)
-                        y2 = y;
-        }
-        s->prop[GRAIL_PROP_PINCH_X1] = x1;
-        s->prop[GRAIL_PROP_PINCH_Y1] = y1;
-        s->prop[GRAIL_PROP_PINCH_X2] = x2;
-        s->prop[GRAIL_PROP_PINCH_Y2] = y2;
+        gru_compute_bbox(&min, &max, frame);
+        s->prop[GRAIL_PROP_PINCH_X1] = min.x;
+        s->prop[GRAIL_PROP_PINCH_Y1] = min.y;
+        s->prop[GRAIL_PROP_PINCH_X2] = max.x;
+        s->prop[GRAIL_PROP_PINCH_Y2] = max.y;
         s->nprop = 7;
 }
 
diff --git a/src/grail-gestures.c b/src/grail-gestures.c
index f1e2093..33d848c 100644
--- a/src/grail-gestures.c
+++ b/src/grail-gestures.c
@@ -218,3 +218,27 @@ void gru_end(struct grail *ge, int gid, const struct move_model *m,
                     prop, nprop);
 }
 
+void gru_compute_bbox(struct grail_coord *min, struct grail_coord *max,
+                      const struct touch_frame *frame)
+{
+        float x, y;
+        int i;
+        if (frame->nactive < 1)
+                return;
+        x = frame->active[0]->prop[TP_POS_X];
+        y = frame->active[0]->prop[TP_POS_Y];
+        min->x = max->x = x;
+        min->y = max->y = y;
+        for (i = 1; i < frame->nactive; i++) {
+                x = frame->active[i]->prop[TP_POS_X];
+                y = frame->active[i]->prop[TP_POS_Y];
+                if (x < min->x)
+                        min->x = x;
+                if (y < min->y)
+                        min->y = y;
+                if (x > max->x)
+                        max->x = x;
+                if (y > max->y)
+                        max->y = y;
+        }
+}
diff --git a/src/grail-gestures.h b/src/grail-gestures.h
index e716757..edd641b 100644
--- a/src/grail-gestures.h
+++ b/src/grail-gestures.h
@@ -68,6 +68,8 @@ void gru_event(struct grail *ge, int gid,
 void gru_end(struct grail *ge, int gid,
              const struct move_model *move,
              const grail_prop_t *prop, int nprop);
+void gru_compute_bbox(struct grail_coord *min, struct grail_coord *max,
+                      const struct touch_frame *frame);
 
 struct combo_model {
         int active, gid;