Hi Roland,

The alternative to multiple group sets is:

The "most atomic" groups are specified. So if two groups (in your model) have a subset of common parts, in my model _three_ rigid groups are defined: the common parts, and the unique parts for each group. Each of your groups is a set of groups in my model.

The advantage to your model is the groups are bigger and there are fewer of them - animations that are not used once the model is complete do not make the model more complex.

But I would argue that if there are different animations using different overlapping groups, then the real model simply has a more complex potential set of actions than either animation describes. We would not say that a minifig does not have moving legs just because we are only animated its head moving. :-)

Building the model is a different and trickier problem, because a set of parts might have reasonable motion in one step but not another. For example, you build a quad out of technic bricks and pins. It has four rigid bodies and two degrees of freedom.

Then in a later step you apply a diagonal brace. The whole structure is locked and it is a single rigid body. My model does not handle this case well.

I think building instructions are a particular case where we might want to consider an extension particular to "build by animation" (e.g. a model where something is built in one position and moved later) - the motions are really 'edits' to the model that fundamentally change it.

cheers

Ben

The alternative to multiple group sets is:

The "most atomic" groups are specified. So if two groups (in your model) have a subset of common parts, in my model _three_ rigid groups are defined: the common parts, and the unique parts for each group. Each of your groups is a set of groups in my model.

The advantage to your model is the groups are bigger and there are fewer of them - animations that are not used once the model is complete do not make the model more complex.

But I would argue that if there are different animations using different overlapping groups, then the real model simply has a more complex potential set of actions than either animation describes. We would not say that a minifig does not have moving legs just because we are only animated its head moving. :-)

Building the model is a different and trickier problem, because a set of parts might have reasonable motion in one step but not another. For example, you build a quad out of technic bricks and pins. It has four rigid bodies and two degrees of freedom.

Then in a later step you apply a diagonal brace. The whole structure is locked and it is a single rigid body. My model does not handle this case well.

I think building instructions are a particular case where we might want to consider an extension particular to "build by animation" (e.g. a model where something is built in one position and moved later) - the motions are really 'edits' to the model that fundamentally change it.

cheers

Ben