ShapeCommand

Remarks

Doc 24's D6 on the undo stack, and it records no geometry at all. A parametric entity's mesh is a function of its parameters, so putting the parameters back is what puts the mesh back — exactly, and for four numbers rather than for a copy of the mesh. That is the one place this differs from EditMeshCommand, which has to record whole meshes because a topology change has no inverse.

⚠ Demoting records nothing either, and leaves the geometry exactly where it is. The mesh a shape generated is already in the document; taking the parameters away changes nothing about it. An undo puts them back and regenerates — which produces the same mesh, because nothing has edited it yet: the first edit is its own entry on the stack and is undone first.

⚠ Two parameter edits of one shape merge and two of different shapes do not. Dragging a corridor's width field is one decision made over forty frames, and forty entries for it is the shape of every "undo did not undo what I did" report — the same argument EditMeshCommand makes about a gizmo drag. A demotion never merges with anything, because it is a different kind of act and one people are entitled to step back over on its own.

Fields and properties (3)

• public string Name

  What this is called in the undo history, as a person would say it.

• public bool IsDemotion

  Whether this is the one-way door rather than a change of numbers.

• public Entity Entity

  Which entity's shape it changes.

Methods (5)

• public static ShapeCommand Set(SceneDocument document, Entity entity, ShapeParameters parameters, string name = "Shape")

  Records giving an entity a shape, or changing the one it has.

• public static ShapeCommand Demote(SceneDocument document, Entity entity, string name = "Make Editable")

  Records the demotion: the parameters go and the geometry stays.

• public void Do(EditorContext context)

  Applies the change.

• public void Undo(EditorContext context)

  Puts back exactly what Do changed.

• public bool TryMergeWith(IEditorCommand previous, out IEditorCommand? merged)

  Absorbs the entry below this one, so that the two become one undo step.

Used by (5)

• BlockoutBooleanVixen.Editor.Blockout
• BlockoutCreateVixen.Editor.Blockout
• BlockoutHandoffVixen.Editor.Blockout
• MeshEditVixen.Editor.SceneView
• SceneCloneVixen.Editor.SceneView