View Full Version : Moving camera long line of site

08-26-2005, 10:03 AM
I have a camera aimed a null so I can control its focal point. I want to be able to move the camera toward the focal point along its line of site, but can't seem to figure out how to do it (other than move freely, then switch views and adjust its position again). Another 3D app I use allows me to hold the Command key (Mac) down and it move the camera long the line of site.

Anything similar in Lightwave?



08-26-2005, 10:11 AM
The simplest way is to switch to use local coordinates under Modify-General-Coord System, this will then allow you to pull the camera along it's local Z axis (which is its line of sight) by dragging the blue line of the camera's handle...

Another way to do it... and isolate any type of motion, rotation etc would be to use parent coordinates...

Start with a null at 0,0,0
Put the camera at x0,y0,z-1
Parent the camera to the null
Then rotate the null as desired to get the view you want, this will also rotate the camera around the null.

Now you can move the camera along its own Z-axis, which will move it along it's line of sight toward/away from the null...

Sometimes it's quite useful to build your scenes with extra nulls that are used to isolate and control specific channels of motion like this... usually in more complex scenes...

Sometimes I use the second method if I'll be doing a lot of precision movements along the constrained channels because that way you can use coordinate system set to parent, and see in the numeric readout at the bottom left the actual channel you're working on, so moving on the camera's z-axis only changes the z number... Using the first method (local coords) shows the coordinates in the lower left in world coordinates, so moving along the z axis changes all three numbers making it more difficult to know what you're doing...


08-26-2005, 12:45 PM
If the other app you're referring to is EI, then the closest thing I've ever been able to find is this:

1. Uncheck the X and Y position fields in the lower left hand corner. (The little boxes that show the coordinate locations.) Leave Z on.

2. In the camera window hold down the Control key and left click and drag up and down. This restricts the camera movement to the Z axis.

(You can drag left and right to move as well, since the other directions are locked out, but going up and down you get much more movement.)

08-27-2005, 03:15 PM
Great, thanks for the help. I'll give these ideas a try.