Combine swipe gestures into a single drag gesture

[libs/gui.git] / source / input / gesturedetector.cpp

diff --git a/source/input/gesturedetector.cpp b/source/input/gesturedetector.cpp
index 112121ee456a86736876b01e23c09a394045c498..cc027973fdc868a319bdce0fe5db5b312ed742a5 100644 (file)
--- a/source/input/gesturedetector.cpp
+++ b/source/input/gesturedetector.cpp
@@ -26,14 +26,8 @@ GestureDetector::GestureDetector(Touchscreen &ts):
 
 string GestureDetector::get_button_name(unsigned btn) const
 {
-       if(btn==GESTURE_SWIPE_DOWN)
-               return "Swipe down";
-       else if(btn==GESTURE_SWIPE_UP)
-               return "Swipe up";
-       else if(btn==GESTURE_SWIPE_LEFT)
-               return "Swipe left";
-       else if(btn==GESTURE_SWIPE_RIGHT)
-               return "Swipe right";
+       if(btn==GESTURE_DRAG)
+               return "Drag";
        else if(btn==GESTURE_PINCH)
                return "Pinch";
        else
@@ -133,9 +127,13 @@ void GestureDetector::start_gesture()
                TouchPoint &p2 = points[1];
                float ddx = p.down_x-p2.down_x;
                float ddy = p.down_y-p2.down_y;
-               if(p.x*p2.x+p.y*p2.y<0 && (p.x*ddx+p.y*ddy)*(p2.x*ddx+p2.y*ddy)<0)
-                       /* If the points moved in different directions and also both away from
-                       or towards the other, it's a pinch gesture. */
+               float away = p.x*ddx+p.y*ddy;
+               float turn = p.y*ddx-p.x*ddy;
+               float away2 = -(p2.x*ddx+p2.y*ddy);
+               float turn2 = -(p2.y*ddx-p2.x*ddy);
+               if(away*away2>0 && abs(away)>abs(turn) && abs(away2)>abs(turn2))
+                       /* If the points moved away from or towards each other without rotating
+                       significantly, it's a pinch gesture. */
                        current_gesture = GESTURE_PINCH;
                else
                        invalid_gesture = true;
@@ -149,20 +147,10 @@ void GestureDetector::start_gesture()
        }
        else
        {
-               // Allow a maximum deviation of about 26° to recognize a swipe gesture.
-               if(abs(p.x)>2*abs(p.y))
-                       current_gesture = (p.x>0 ? GESTURE_SWIPE_RIGHT : GESTURE_SWIPE_LEFT);
-               else if(abs(p.y)>2*abs(p.x))
-                       current_gesture = (p.y>0 ? GESTURE_SWIPE_UP : GESTURE_SWIPE_DOWN);
-               else
-                       invalid_gesture = true;
-
-               if(current_gesture!=GESTURE_NONE)
-               {
-                       active_points = 1;
-                       set_axis_value(0, p.down_x, true);
-                       set_axis_value(1, p.down_y, true);
-               }
+               current_gesture = GESTURE_DRAG;
+               active_points = 1;
+               set_axis_value(0, p.down_x, true);
+               set_axis_value(1, p.down_y, true);
        }
 
        update_progress();
@@ -175,14 +163,11 @@ void GestureDetector::update_progress()
 {
        TouchPoint &p = points[0];
 
-       if(current_gesture==GESTURE_SWIPE_DOWN)
-               set_axis_value(2, -p.y, true);
-       else if(current_gesture==GESTURE_SWIPE_UP)
-               set_axis_value(2, p.y, true);
-       else if(current_gesture==GESTURE_SWIPE_LEFT)
-               set_axis_value(2, -p.x, true);
-       else if(current_gesture==GESTURE_SWIPE_RIGHT)
+       if(current_gesture==GESTURE_DRAG)
+       {
                set_axis_value(2, p.x, true);
+               set_axis_value(3, p.y, true);
+       }
        else if(current_gesture==GESTURE_PINCH)
        {
                TouchPoint &p2 = points[1];
@@ -193,6 +178,7 @@ void GestureDetector::update_progress()
                float dx = ddx+p.x-p2.x;
                float dy = ddy+p.y-p2.y;
                set_axis_value(2, sqrt(dx*dx+dy*dy)/sqrt(ddx*ddx+ddy*ddy)-1, true);
+               set_axis_value(3, 0, true);
        }
 }