By default, the program creates new two-dimensional entities with a zero elevation and thickness. The easiest way to create a three-dimensional entity is to change the elevation or thickness property of an existing two-dimensional entity.
The elevation of an entity is its z-coordinate position in relation to the xy plane in which the entity is drawn. An elevation of 0 indicates that the entity is drawn on the xy plane of the current UCS. Positive elevations are above this plane; negative elevations are below it.
The thickness of an entity is the distance it is extruded above or below its elevation. A positive thickness extrudes the entity upward in the positive z direction of the entity; a negative thickness extrudes it downward in the negative z direction. The thickness is applied uniformly to the entire entity. You can extrude any two-dimensional entity into a three-dimensional entity by changing the thickness of the entity to a nonzero value. For example, a circle becomes a cylinder, a line becomes a three-dimensional plane, and a rectangle becomes a box.
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Two-dimensional entities. |
Two-dimensional entities with thickness added. |
You can create three-dimensional entities using any of the following methods:
You can change the default elevation and thickness values to create new entities with an elevation and thickness already applied.
Tell me about...
Creating three-dimensional entities
Setting the current elevation and thickness using a dialog box
How do I...
Change the thickness and elevation of an existing entity
Create a three-dimensional face