Games [XUI2D] First Joints Demo


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The first version of XUI2D and the X2 framework are almost ready. Joints are now being added.
The joints feature is a very powerful feature of box2d and can be used to implement complicated physical structures.

X2TileMap was also improved and it now properly supports rotated objects.

There is almost no code in the above example except of the template code.
The objects are defined with Tiled editor:


This code adds the joints between the elements based on the "hinge" objects positions:
Private Sub CreateChain
   Dim elements As List
   For Each ElementName As String In Array("pole 1", "chain 1", "chain 2", "chain 3", "chain 4", "chain 5", "chain 6", "pole 2")
       elements.Add(TileMap.CreateObject2ByName(ObjectLayer, ElementName))
   For i = 0 To elements.Size - 2
       CreateJoint(elements.Get(i), elements.Get(i + 1), "hinge " & (i + 1))
End Sub

Private Sub CreateJoint(BodyA As X2BodyWrapper, BodyB As X2BodyWrapper, HingeName As String)
   Dim revdef As B2RevoluteJointDef
   revdef.Initialize(BodyA.Body, BodyB.Body, TileMap.GetObjectTemplateByName(ObjectLayer, HingeName).BodyDef.Position)
End Sub

Good tutorial about joints: