Add rotation gesturev1.0-alpha3

Moving two fingers around a center point will trigger the gesture.
This patch computes the rotation gesture and maps it to mouse buttons
14 and 15.

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

1 files changed, 13 insertions, 2 deletions

diff --git a/src/gestures.c b/src/gestures.c
index 03ec96d..2dafe79 100644
--- a/src/gestures.c
+++ b/src/gestures.c
@@ -74,7 +74,8 @@ static void extract_movement(struct Gestures *gs, struct MTouch* mt)
         float xm[DIM_FINGER], ym[DIM_FINGER];
         float xpos = 0, ypos = 0;
         float move, xmove = 0, ymove = 0;
-        float rad, rad2 = 0, scale = 0;
+        float rad, rad2 = 0, scale = 0, rot = 0;
+
 
         if (!nmove || nmove != npoint)
                 return;
@@ -116,13 +117,23 @@ static void extract_movement(struct Gestures *gs, struct MTouch* mt)
                 rad2 += yp[i] * yp[i];
                 scale += xp[i] * xm[i];
                 scale += yp[i] * ym[i];
+                rot += xp[i] * ym[i];
+                rot -= yp[i] * xm[i];
         }
         rad2 /= nmove;
         scale /= nmove;
+        rot /= nmove;
         rad = sqrt(rad2);
         scale /= rad;
+        rot /= rad;
 
-        if (abs(scale) > move) {
+        if (abs(rot) > move && abs(rot) > abs(scale)) {
+                gs->rot = rot;
+                if (gs->rot) {
+                        if (nmove == 2)
+                                SETBIT(gs->type, GS_ROTATE);
+                }
+        } else if (abs(scale) > move) {
                 gs->scale = scale;
                 if (gs->scale) {
                         if (nmove == 2)