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R67 / Generalization

Stem is a Floating Stem or Anchored Stem

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An Anchored Stem is positioned by the user with an Anchor position. This position is later resolved to diagram coordinates. Anchored Stems are used in all Connector Types.

A Floating Stem is lined up with an opposing Anchored Stem so that a straight line is formed. The pairing of Anchored and Floating Stems is useful in both Binary and Tree Connectors.

With a Straight Binary Connector, there is no need for two user specified anchor positions. Since the Connector is a straight line, only one anchor position is necessary. In fact, there should only be one to ensure that we end up with a non-diagonal line when the coordinates are resolved.

The non-anchored Stem in a Straight Binary Connector is understood to float so that it is level with the opposing Anchored Stem. The position of a Floating Binary Stem is computed for a horizontal line by sharing the x coordinate of the opposing Anchored Stem. This is the y coordinate if the line is vertical.

The same situation can occur in a Tree Connector where one Leaf Stem is anchored while another is lined up with it straight across.

Constraint

ID + Connector in either subclass or ID + Connector + Stem type + Node + Face + Anchor position in the Anchored Stem subclass. Two different ID’s are referenced since the Anchored Stem is enforcing a constraint preventing two Anchored Stems from being placed in the same location on the same Node face.

Note: Will probably change the mechanism formalizing this constraint since the superclass ID references need to be the same