Dragging objects with touch joints under gravity

http://developer.anscamobile.com/content/game-edition-physics-joints#Dragging_objects_with_touch_joints

I’ve noticed that if the code sample on the above page is modified so that it has gravity:

physics.setGravity( 0, 10 )

and if the line:

body.tempJoint:setTarget( event.x, event.y )

is changed to read

body.tempJoint:setTarget( event.x, body.y ) – altered event.y to say body.y

Then there is no difference when dragging the object. If the y value is set to something which is changing then there is a visible change, or if the touch stops moving. However, setting the target to to only update the x value and hoping the y value will still be subject to the effects of gravity fails.

Does anyone know why?

m [import]uid: 8271 topic_id: 2240 reply_id: 302240[/import]