Yeah using the Ageia sdk you can add pressure to a closed cloth shape (like the red inflated cow example that comes with the SDK). You can present your case to them and they might give you access to the sdk downloads including the rocket app, and the other cloth samples.
But it seems DarkPhysics is a very simple implementaion of the Ageia sdk. Lots of things are missing like the ability to inflate cloth you mentioned. I hope they plan on fleshing out DarkPhysics and fixing some of the bugs.
Mr. Davey, do you plan on regularly expanding the command set of DarkPhysics to mirror the latest Ageia sdks? That would be great if you would. Their newest release allows you to make 'dentable' objects - they give the theoretical example of a physics car that when you run it into a telephone pole, the front end smashes in, affecting the driving physics. This is also demonstrated in the same example that the red inflated cloth cow shows up in (the last selection - red oil drums that you can pummel with spheres and put dents in them.)
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