By Dennis Collin
This is a common topic that Cadline covers in a 3ds Max essentials class. It is in fact very easy to do once you have grasped the basics of Max concepts.
Open up your model and draw or import a nicely curved spline object, ideally one without any kinks or sharp corners. You can set a height for the path to represent the 'head' height but actually with this following tip it isn't really necessary as the application will do much of the tedious setup for you!
The routine is called the Camera Walkthrough Assistant and originates from a script that came with an early version of Max which in turn was borrowed, from Max's retired sister product 3d Studio Viz.
Walkthrough Assistant can be located under the animation menu, and is highlighted below.
Upon starting the routine a dialogue box is displayed where it can create a camera or use an existing camera, set the type free or target and ultimately pick the path you want the camera to follow.
Other controls include constant speed, setting the eye level follow the path (so camera is always looking ahead of where its going) Field of View etc..
Note it is recommended to have at least several hundred frames in your Max scene before selecting your path for a serious walkthrough.
Before committing many hours to a final render, generate a quick preview similar to above to ensure that the walkthrough performs as desired. (Tools, Preview - grab Viewport, Create Preview Animation) For any adjustments, pausing use the Track View tools as normal.
In 3ds Max of course it is possible to get other objects to follow paths, including people and vehicles etc.. This process I will cover in the near future as well as the aforementioned Track view tools.
N.B If you are a Vray user and wish to apply this animation to a Vray Camera then this utility will not work. Instead you will need to use the alternative method which I will go over in due course.