Drag with Phys2D

Game Mechanics
#1

Hello.

How can I drag boxes like in this example http://www.jbox2d.org/v2demos/ but using Phys2D ???

#2

It is how I should do it (can’t test it right now) :

  • On mouse press, create a small body A that can’t collid with anything ( mask = 0, if I remember) where the mouse is, and create a fixed joint between this body and the body you want to move.
  • Each step create a force from the position of the body A and the mouse position (like Force = c* (Mouse - PositionA)) and apply it to the body A
  • On mouse release, remove the joint and the body A
#3

Thank you!! I tried that and it worked!!
I had to add this: Every time a drag event occurs I update the body A position to the current x,y mouse.

But I have a problem. body A is colliding with other objects.
I set the mask=0 as you said A.setBitmask(0); but it is still colliding :-\

#4

Update the force or the position every frame. I use force because i was think that the object will warp if I use position.

Try to give a none-0 mask to all other bodies.

Basicly mask work like this :
if (bodyA.getMask()&bodyB.getMask() != 0) { doCollisionTest(bodyA,bodyB); }

But may be there is a special case when all mask are 0.