Viewing a 3D model

A 3D view can display part of the design cube from any point, looking in any direction.

• As in 2D, elements to the left, right, above, or below, can be excluded from a view by zooming in or windowing so that the elements are outside the view's area.

• 3D views also have depth. You can exclude the display of elements located in front of, or behind, a required object by changing the view's Display Depth, or by applying a clip volume.

3D viewing procedures that are similar to 2D

Many 3D viewing procedures are similar to their 2D counterparts. For example, you can change a view's area using the same tools as for 2D. Tools such as the Window Area, Zoom In, and Zoom Out view controls are used. For more information about these view controls, see View Control Bar.

Fitting views in 3D

The Fit View view control has some 3D-specific aspects and settings.

Expand Clipping Planes	If on, the view's Display Depth is adjusted, along with the view origin and magnification, so that all elements on levels that are on for the view are displayed.
Center Active Depth	If on, centers the Active Depth in the fitted view. (It is recommended that you turn on Center Active Depth when fitting a view you intend to dynamically rotate, or a view whose perspective you intend to change.)
Center Camera	If on, centers the Camera in the fitted view.

When a clip volume has been applied to a view, the Fit View tool has no effect on the volume displayed in the view, it merely fits the view to the elements contained within the applied clip volume.

Rotating views in 3D

The Rotate View view control is used in 3D to rotate a view to one of the standard views as well as to custom orientations. For custom rotations, the Rotate View view control gives you two options for visual feedback during view rotation. With Method set to Dynamic and:

• Dynamic Display turned off — a dynamically displayed cube helps you define the rotation.

• Dynamic Display turned on — you see the elements rotate dynamically as you rotate the view.

When rotating views in 3D, an important point to consider is the axis about which you want the view to rotate. During a view rotation, the first data point that you place defines the rotation axis. In 3D, this also defines the depth in the view of the rotation axis. Entering the data point in a vacant part of the view means that the rotation axis is on the Active Depth. If this is far behind the elements in the view, then you can quickly rotate the model out of sight. A simple way around this is to first snap to an element in the view and then accept with a data point. This will set the rotation axis at the depth of the snapped element and force rotation about the snap point on the element.

To dynamically rotate a view in 3D using a cube

1. Select the Rotate View view control.


2. Set Method to Dynamic and check that Dynamic Display is turned off.


3. Enter a data point in the view to rotate (this will be the point about which rotation will occur).
   A cube representing the view volume dynamically displays. To further assist you, one of the cube's faces is displayed in a heavier line weight indicating the front face. As you move the screen pointer, the cube rotates to show you the amount of rotation. The location of the original view is shown as a cube in a lighter weight line.


4. Enter a second data point to complete the rotation.

To dynamically rotate a view using dynamic display

1. Select the Rotate View view control.


2. Set Method to Dynamic.


3. Turn on Dynamic Display.


4. Enter a data point in the view to rotate (this will be the point about which rotation will occur).
   As you move the screen pointer from this first data point, the view is rotated. The elements also rotate dynamically with the view.


5. Enter a second data point to define the view orientation.

To rotate a view in 3D by three points

1. Select the Rotate View view control.


2. Set Method to 3 Points.


3. Enter a data point to select the view to rotate and to define the origin of the view x-axis.
   The origin, as well as a dynamic line indicating the positive direction of the view x-axis, displays in all views where it is possible.


4. Enter a data point to define the positive direction of the view x-axis.
   A rectangle that indicates the new view boundary displays only in the view that is being rotated.


5. Enter a data point in any view to define the positive direction of the view y-axis and rotate the view.

To rotate a view(s) in 3D to a standard orientation

1. Select the Rotate View view control.


2. Set Method to the desired standard orientation — Top, Front Right, Isometric, Bottom, Back, Left, or Right Isometric.


3. Select the view(s).

Panning views in 3D

Panning in 3D models, using the Pan View view control, gives you two options for determining the amount to pan the view. If Dynamic Display is off, a dynamic cube is displayed between the origin and the pointer (rather than an arrow as in 2D), indicating the distance and direction that the view will be moved. If Dynamic Display is turned on, then the elements in the view are panned dynamically.

3D-specific viewing procedures

In addition to the familiar 2D viewing procedures, in 3D you can:

• Limit the depth of the view volume using the Set Display Depth view control.

• Change the perspective angle of a view using the Change View Perspective view control or the Camera Settings view control.

Display of the view volume in the other views is apparent only when they display the same volume of the design cube as the selected view. Where necessary, you can use the ALIGN key-in to ensure that views are displaying similar volumes of the design cube.

To align two views to display the same volume

1. Key in ALIGN.


2. Select the source view.


3. Select the view(s) to align with the source view.
   The second (and other) selected target view updates to display (at least) the same volume of the model as displayed in the source view. The orientation of the target views is not changed, only the view volume.

Using saved views in 3D

Creating saved views in 3D is identical to 2D. Like 2D saved views, those in 3D modeling “remember” various parameters concerning the view, which levels are on and off in both the active model and any references, and the region of the model that is displayed. Additionally, the Display Depth is saved with a 3D saved view, as is the Clip Volume if one is applied.

The following categories of settings can be saved with a saved view:

• window aspect ratio, size, or size and position

• camera position

• view attributes

• clip volume

• level display

• reference settings

When creating saved views in 3D, thought should be given to the Display Depth and Clip Volume (if applied).