You can view the parallel projection of a 3D model from any point in model space. To determine the point or angle in model space, you can
Viewing in 3D is available only in model space. If you are working in paper space, you cannot use VPOINT, DVIEW, or PLAN to define paper space views. The view in paper space is always a plan view.
A quick way to set a view is to choose one of AutoCAD LT's predefined 3D views. You can select predefined standard orthographic and isometric views by name or description by choosing 3D Viewpoint from the View menu. These views represent commonly used options: Top, Front, Left, Right, and Back. In addition, you can set views from isometric options: SW (southwest) Isometric View, SE (southeast) Isometric View, NE (northeast) Isometric View, and NW (northwest) Isometric View.
To understand how the isometric views work, imagine you are looking down at the top of a box. If you move toward the lower-left corner of the box, you are viewing the box from the SW Isometric View. If you move toward the upper-right corner of the box, you are viewing it from NE Isometric View.
You can define a viewing direction by entering the coordinate values of a point. This point represents your position in 3D space as you view the model while looking toward the origin (0,0,0). Viewpoint coordinates are relative to the World Coordinate System unless you change the WORLDVIEW system variable. The conventions for defining standard views differ between AEC and mechanical design. In AEC the perpendicular view of the XY plane is the top or plan view; in mechanical design, the perpendicular view of the XY plane is the front view. Procedures for defining views with either convention are provided in the list of procedures for this topic.
You can also rotate a view using the Rotate option of 3D Viewpoint. The illustration shows a view defined by two angles relative to the X axis and the XY plane of the WCS. This is the same convention as used for entering spherical coordinates.
In AutoCAD LT, a plan view is a view aimed toward the origin (0,0,0) from a point on the positive Z axis. This results in a view of the XY plane. You can change the current viewpoint to a plan view of the current UCS, a previously saved UCS, or the WCS.
You can restore the view and coordinate system that is the default for most AutoCAD LT drawings by setting the UCS orientation to World and then setting the viewpoint to plan view.
With dynamic viewing, you can display the effects of changing your viewpoint as you make the changes. Using this method, you can also simplify your view temporarily by choosing only the objects that you need to determine the view. Alternatively, if you press ENTER without selecting any objects, 3D Dynamic View displays a model of a small house instead of your actual drawing. You can use this house to define the viewing angle and distance. When your adjustments are complete and you exit the command, AutoCAD LT applies the changes to the entire 3D model in the current view.
You can create cutaway, or section, views of your drawing by positioning front and back clipping planes that control the visibility of objects based on their distance from a theoretical camera. You can move the clipping planes perpendicular to the line of sight between the camera and target (where the camera is pointing). Clipping removes the display of objects from the front and back of clipping planes. The following figure shows how clipping planes work:
