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Unity Ragdoll and Collisions with Rigidbodies with Kinematics

In my last post http://vackup.blogspot.com.ar/2013/11/unity3d-kill-character-and-make-him-die.html I wrote how kill a character (that uses a rigidbody) and make him die like a ragdoll. The solution was simple, just add him a ragdoll with Unity Ragdoll wizard and set all rigidbodies as Kinematic.

This was working great but all characters don't collide and they pass through other objects. Ouch!!

Searching the internet, I found that "If isKinematic is enabled, Forces, collisions or joints will not affect the rigidbody anymore.http://docs.unity3d.com/Documentation/ScriptReference/Rigidbody-isKinematic.html

Also I found that someone had the same problem I have "I can't seem to find a specific answer for this. Mainly, I have an enemy rigidbody in my game who, when hit by an attack of some large value, goes ragdoll (isKinematic = false). However, when he is chasing the Player with isKinematic = true, he phases through terrain and such. Is there an elegant way of having an enemy be allowed to go into ragdoll and still collide with the environment?http://answers.unity3d.com/questions/167712/collisions-with-rigidbodies-with-kinematics.html

And the reply was something I don't want to hear "Actually the only two components that can detect collisions are: the CharacterController and a non-kinematic RigidBody without any exceptions (afaik). However the CharacterController uses it's own detection method and is not really part of the physics system.

The only difference between a simple GameObject with a collider and one with a kinematic Rigidbody attached is that the kinematic Rigidbody can wake up other non-kinematic Rigidbodies. Non-kinematic Rigidbodies fall asleep after a few seconds. They can only detect collisions when they are awake. If you move a GameObject with a sleeping Rigidbody it will wake up automatically, no matter what method of movement you're using (transform.position, AddForce, MovePosition).

The only use of a kinematic Rigidbody is that when you move it into a sleeping Rigidbody it will wake up and would perform the collision check. Keep in mind that the collision messages are sent to both objects but only a non-kinematic Rigidbody can produce them.

I'm not sure how your ragdoll-setup looks like, usually you have multiple body parts that are connected with joints. To move the enemy while he's alive you should use either a CharacterController, or a non kinematic Rigidbody. You should remove it when you turn it into a ragdoll.

If you use a Rigidbody you can set freezeRotation to true so the Rigidbody is not rotated by the physics system but you're still able to rotate the object via script. You can also use Rigidbody.constraints to prevent the rotation and / or position change caused by the physics system."

So I started to think what can I do ... I thought that if isKinematic wasn't my solution, it would be great if I could create the ragdoll at runtime using a script.

So I searched the internet and found someone asking how to "Export ragdoll setup to script" (http://answers.unity3d.com/questions/188917/export-ragdoll-setup-to-script.html). The reply was "I created a code generator for C# and released it as open source under MIT license. Further on I wrote an article in my blog where you can find the code as well". He was talking about C# Code Generator As Add-on for Unity3D Ragdoll Wizard

There you can find the code to download and how to use it. I use it in my project and the result is what I was trying to achieve. The results are here: http://bit.ly/1beCGTg