Make an Invisible Cube in Composer - Method 1

Recently I was teaching a Composer class during which we were discussing how to make walk through videos by using Composer’s “Attach Camera ‘Move-With’ (Rigid attachment)”.  If you’ve been to our class you know how we teach it.  If not it’s your lucky day.  I’m going to walk through the way we usually capture awesome videos walking around an environment quickly without adding a bunch of camera keys.

Create a primitive inside Composer

Grab the initial position of the primitive with a location key

Use Auto-keys,move to a time a while later, and transform your primitive:

At the start of the motion create a camera pointing how you want (just use the viewport), assign the camera for the animation

Select a face of the primitive and use “Attach Camera ‘Move-With’ (Rigid attachment)”

Voila camera moves around following the primitive like a sweet first person action game.  And you don’t have to create a bunch of camera keys.

This method is really easy to move a camera around because all we have to do is move the cube around.  It’s pretty easy to think “how would I shoot this with a camera if I were actually going to walk around?”  Well that’s what the cube does and what the camera will do.

It’s at this point a student will say “Well that’s wonderful, but I don’t want to see a big blue cube moving around my assembly”.

Then we the instructors get to be heroes and reply, “Exactly, so let’s turn the Opacity way down to 1!”

“But why 1, why not zero?!” a fictitious student exclaims.

Now being the wise, all knowing, and all powerful instructors we are, we respond back, “Well let’s see what happens if we use zero…” After adjusting it to zero, which we’ve done many times before, the students see the camera doesn’t move.

(There’s no video here…what am I supposed to show nothing happening?!?)

“When the opacity is set to zero Composer doesn’t recognize the primitive and has nothing to follow.  It’s like we’ve hidden the primitive. We set the opacity to 1 and Composer can follow the cube, but we the users can’t see the cube…” So we adjust the opacity back to 1 and play the video again as the students cheer in delight at their new skill set.

This is where the story usually ends, until last week’s training when my buddy Tommy said, “I can see the cube.”

“LIES! DIRTY ROTTEN LIES!” I screamed as I stormed to where Tommy was sitting. I needed to see my video playing on our projector from Tommy’s vantage point and as the video looped, I saw it.  There it was plain as day……the primitive….

To continue see Make an Invisible Cube in Composer – Method 2!

Brandon Nelms
Application Engineer
Computer Aided Technology, Inc