Hello everyone, I expose briefly the problem. I wrote a python module that allows me to interact with the Blender game engine using the device Leap Motion. The only problem that I find concerns with the rotation of the objects performed with the palm of the hand.

I want you to notice that the exact same code works right when it runs outside of the blender game engine as an add-on.

I’ll post my update function of the orientation of the object right down and a short video of the result

```
def update(self, leap_dict):
#print("rotation:
" + str(self.target_object.localOrientation))
if(self.use_finger):
pointable = self.pointable_selector.select(leap_dict)
if(pointable == None):
return
dir = mathutils.Vector(pointable["direction"])
if(self.pointable_start_direction == None):
self.pointable_start_direction = mathutils.Vector(dir)
# Rotation with respect to the original pointable direction
delta_rot = self.pointable_start_direction.rotation_difference (dir)
else: # Use hand palm
hand = self.hand_selector.select(leap_dict)
if(hand == None):
return
h_x = mathutils.Vector(hand["direction"])
h_y = mathutils.Vector(hand["palmNormal"])
h_z = h_x.cross(h_y)
# Build the rotation matrix using the data of the 3 orthogonal vectors (hand direction, palm normal, and their outgoing cross product)
rot_mat = mathutils.Matrix.Rotation(0, 3, 'X')
rot_mat[0][0], rot_mat[1][0], rot_mat[2][0] = h_x[0], h_x[1], h_x[2]
rot_mat[0][1], rot_mat[1][1], rot_mat[2][1] = h_y[0], h_y[1], h_y[2]
rot_mat[0][2], rot_mat[1][2], rot_mat[2][2] = h_z[0], h_z[1], h_z[2]
rot = rot_mat.to_quaternion()
if(self.palm_start_rotation == None):
self.palm_start_rotation = rot
# Rotation with respect to the original palm rotation
delta_rot = rot * self.palm_start_rotation.inverted()
# rotate the delta vector according to the view matrix
cam_rot = self.view_matrix.to_quaternion()
delta_rot = cam_rot.inverted() * delta_rot * cam_rot
# New rotation
new_rot = delta_rot * self.target_object.localOrientation.to_quaternion( )
#Finally put it in there
if(self.target_object != None):
self.target_object.localOrientation = new_rot
```

[video]https://www.dropbox.com/s/ypppox5j2av64xo/Screen%20Capture%20Tool_2013-11-14%2020.38.08.mov[/video]

I hope some of you should know how to help me…