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ScaleTool does not scale default coordinates #2660

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@clnsmith

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@clnsmith

The scale tool does not affect default coordinates.

If a model has a translational DOF with a non zero default coordinate, it makes sense to me that this should be scaled. For example, in a patellofemoral joint where the femur frame is between the condyles and the patella coordinate system is located at the patella COM, the default coordinate value for AP translation must be non-zero for the patella to be in a a reasonable anatomic location in the default model pose. Currently, if this model is scaled, the default coordinate does not change, so if the scale factors are > 1 the patella in the scaled model is inside the femur bone.

The slighty complicated piece to this is that the parent and child bodies may have different scale factors. So the default coordinate could either be scaled by the parent scale factors, or the average of the parent and child scale factors.

I don't think rotational DOFs should be affected by scaling.

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