Shapes are collections of handle and/or node perturbations from the initial configuration of the FE mesh before the morph.  When you morph your model, HyperMorph stores the morph internally as a collection of perturbations which you can then undo or redo.  When you create a shape using the save shape subpanel on the Morph panel or Freehand panels, the handle and/or node perturbations are stored in the new shape entity along with biasing factors for the handle perturbations and details such as the biasing style.  HyperMorph takes the difference between the initial state of the model and the current state of the model when creating a new shape.  If you save the model using the save each morph step option in the Shapes panel, each morph on the undo/redo list will be saved as a separate shape.  To get to the current state of the model from the initial state, all of these shapes must be applied.  Creating shapes allows you to generate shape variables for optimization and store model changes for parametric studies.

For many morphing operations, the morph consists only of handle perturbations.  However, if constraints are being used, or the morph is a mapping or radius changing operation, node perturbations are required to fully describe the shape.  In the case of freehand morphing, the morph consists only of node perturbations.  When you create a shape, vectors are drawn for each handle and node perturbation for the shape.  The vectors are drawn the exact length of the perturbation and the vectors for the handle perturbations are drawn with thicker lines to denote that they are different from node perturbations.  Note that while shapes with handle perturbations will move nodes when they are applied, those shapes do not contain node perturbations and thus vectors are not drawn at those nodes.

When you are saving a shape, you can select whether to save it as handle perturbations or node perturbations. If you select handle perturbations, the shape will be saved as either handle perturbations only, or a combination of handle and node perturbations if node perturbations are required to describe the shape.  If you select node perturbations, the shape will be saved as node perturbations only.  The difference between the two types comes into play if you change the handles or domains in your model.  Shapes saved as node perturbations are not affected by changes to domains and handles, while shapes saved as handle perturbations will differ from shapes that have been saved with changes to the handle influences.  Whenever you make a change to your model, HyperMorph will ask you if you want to preserve any existing shapes saved as handle perturbations by converting them to node perturbations.  If you plan to make changes to domains and handles, you should save shapes as node perturbations.  If not, save shapes as handle perturbations and they will require less memory and disk space.  If you later decide that you want to change a shape from node perturbations to handle perturbations or vice versa you can do so in the convert subpanel of the Shapes panel.

Once a shape is saved, you can apply it to your model with any given scaling factor.  Applying a shape in this way is like any other morphing operation and can be undone, redone, or saved as part of another shape.

 

To convert shapes saved with handle perturbations to shapes saved with node perturbations, or vice-versa:

The shape is converted.

 

See Also:

Morph panel

Freehand panels

Shapes panel