Implement additional two-finger gestures

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

diff --git a/source/input/gesturedetector.cpp b/source/input/gesturedetector.cpp
index d626c5d08efc6dcbd909083651045c7f056c98db..aecfa81bb3b7ab88fb4602956f6ca11368a74634 100644 (file)
--- a/source/input/gesturedetector.cpp
+++ b/source/input/gesturedetector.cpp
@@ -26,16 +26,14 @@ 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_DRAG_2)
+               return "Two-finger drag";
        else if(btn==GESTURE_PINCH)
                return "Pinch";
+       else if(btn==GESTURE_ROTATE)
+               return "Rotate";
        else
                return Device::get_button_name(btn);
 }
@@ -141,8 +139,13 @@ void GestureDetector::start_gesture()
                        /* 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;
+               else if(turn*turn2>0 && abs(turn)>abs(away) && abs(turn2)>abs(away2))
+                       /* If the points both turned in the same direction without significant
+                       changes in distance, it's a rotate gesture. */
+                       current_gesture = GESTURE_ROTATE;
+               else if((p.x*p2.x+p.y*p2.y)>2*abs(p.x*p2.y-p.y*p2.x))
+                       // If both points moved in the same direction, it's a two-finger drag.
+                       current_gesture = GESTURE_DRAG_2;
 
                if(current_gesture!=GESTURE_NONE)
                {
@@ -153,41 +156,36 @@ 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();
 
        if(current_gesture!=GESTURE_NONE)
                set_button_state(current_gesture, true, true);
+       else
+               invalid_gesture = true;
 }
 
 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);
-       else if(current_gesture==GESTURE_PINCH)
+               set_axis_value(3, p.y, true);
+       }
+       else if(current_gesture==GESTURE_DRAG_2)
+       {
+               TouchPoint &p2 = points[1];
+               set_axis_value(2, (p.x+p2.x)/2, true);
+               set_axis_value(3, (p.y+p2.y)/2, true);
+       }
+       else if(current_gesture==GESTURE_PINCH || current_gesture==GESTURE_ROTATE)
        {
                TouchPoint &p2 = points[1];
                /* Pinch progress is the ratio between the current distance of the points
@@ -196,7 +194,16 @@ void GestureDetector::update_progress()
                float ddy = p.down_y-p2.down_y;
                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);
+               if(current_gesture==GESTURE_PINCH)
+               {
+                       set_axis_value(2, sqrt(dx*dx+dy*dy)/sqrt(ddx*ddx+ddy*ddy)-1, true);
+                       set_axis_value(3, 0, true);
+               }
+               else if(current_gesture==GESTURE_ROTATE)
+               {
+                       set_axis_value(2, atan2(dy*ddx-dx*ddy, dx*ddx+dy*ddy)/M_PI/2, true);
+                       set_axis_value(3, 0, true);
+               }
        }
 }