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Collision
This function defines you as a collision volume - a 3D object that can navigate around and interact with the
model, obeying certain physical rules that confine you within the model itself. In other words, you have a mass
and as such, cannot pass through other objects, points or lines in the scene.
You can walk over, or climb over objects in the scene that are up to half the height of the collision volume, thus
allowing you to walk up stairs, for example.
The collision volume, in its basic form, is a sphere (with radius = r), that can be extruded to give it height (with
height = h >= 2r). See diagram below:
The dimensions of the collision volume can be customized for the current viewpoint or as a global option.
NOTE Collision can only be used with the Walk and Fly navigation tools.
When collision is turned on, rendering prioritization is changed so that objects around the camera or avatar are
displayed with much higher detail than normal. The size of the region of high detail is based on collision volume
radius and speed of movement (needing to see what is about to be walked into).
To toggle collision
➤ When using the Walk or Fly tool, click Viewpoint tab ➤ Motion Settings panel ➤ Realism drop-down
➤ Collision check box.
Menu: Classic user interface: Viewpoint ➤ Navigation Tools ➤ Collision
Command entry: CTRL + D
Third Person View
This function allows you to navigate scene from a third person perspective.
When third person is activated, you will be able to see an avatar which is a representation of yourself within the
3D model. Whilst navigating you will be controlling the avatar's interaction with the current scene.
202 | Chapter 6 Explore Your Model