The soft body tag can be used to simulate the physical behavior of soft bodies or cloth. To do that you just have to add the soft body tag to an editable polygon object and turn on Dynamics. For pinning mesh vertices to rigid bodies please use the Anchor tag.

The soft body simulation is performed in the global coordinate system. So the transformation properties of the object are not influenced by a soft body simulation.

The soft body simulation is limited to a max. of 10.000 vertices!!!
Should soft bodies penetrate other objects increasing the Solver Iterations property of the soft body tag or the Accuracy property of the Dynamics settings might help.
Be careful that the margin is never bigger than the closest distance between two mesh vertices since that can pretty fast results in instable simulation results.

Attention: You can only add a soft body tag to an editable polygon object.

Properties

• Mass: Specifies the total mass of the soft body.
• Stiffness: Specifies how stiff the soft body is. Low values result in more elastic objects while higher values generate stiffer objects.
• Damping: Specifies how strong the linear movement of the soft body vertices is damped. The higher the damping value the faster the soft body movement slows down.
• Drag: Specifies how strongly the soft body is influenced by drag forces.
• Lift: Specifies how strongly the soft body is influenced by lift forces.
• Friction: Specifies how strong the soft body is influenced by frictional forces between two objects.
• Volume conservation: Specifies if the volume of the soft body should be maintained when it is squashed.
• Pressure: Specifies the pressure within the soft body. If the pressure within the object is higher than the pressure outside this will blow up the object.
• Recover shape: When using this property the soft body remembers its original shape and tries to recover it.
• Margin: The margin adds some additional collision tolerance. The margin should never be zero.
• Bending constraints: The bending constraints specify the max. adjacency distance of control point influencing each other. For volumetric soft bodies this value should be at least 2. In general it is recommended to keep that value unchanged.
• Two sided: This property is only needed for cloth simulation. It is required that drag and lift forces are applied on both sides of the surface.
• Self collision: Specifies if the soft body is checked for self intersections.
• User clusters: If this property is turned on the mesh itself is no longer used for the collision test but an approximation of the mesh is computed. Hereby the shape of the mesh is approximated by so called clusters.
• Clusters: Specifies the max. number of clusters which are used to approximate the shape of the soft body.
• Solver iterations: The higher this value is the more simulation steps the physics solver will calculate for each simulation frame. So higher values generate more accurate simulations results at the cost of longer calculation times. Especially when soft bodies penetrate into other objects higher solver iterations can solve that problem.