Stick with me for a minute: You’re riding shotgun in the car as your friend drives down the long, flat road through Kansas. Your eyes drift out the window as you watch the lines of the road zip zip zip by at lightning speed. The fence along the side of the road undulates and moves, becoming a silver blur. The cows in the distance slowly move by your window as you pass. The distant grain silo, hundreds of yards away, crawwwwlllsss by, marking your place on this endless landscape.
The lines on the road, the fence, the cow, the silo. They all move at different speeds as you ride through the land. You might see that line on the road for less than half a second, the fence for roughly the same. The cow might be in your view for a full five seconds before he disappears, and the grain silo just seems to never really move at all.
This, in essence, is the principle of Parallax. The term comes from the Ancient Greek word for “alternation”, meaning how things alternate or shift. Astronomers use the principles of parallax motion to measure massive distances as stars move in the sky. For us, we’ll approach parallax from an animator’s standpoint.
Animators have been using parallax principles for years, although to varying degrees of success due to technological limitations. Disney pioneered the use of the multiplane camera to create the illusion of depth and parallax motion.
Here is a short documentary on the subject:
Now, luckily, we don’t need to use a massive multiplane camera in the age of digital animation.
Parallax can be achieved in any number of animation and gaming platforms. Here is an example using Adobe Animate:
There are other techniques to achieve a stronger illusion of depth in a 2D medium. For example, atmospheric conditions make objects in the far distance appear fuzzy or smoky, like distant mountains. Artists utilize this to create a stronger sense of depth through blur and dispersion effects, like in the game Mutant Mudds:
Using all these techniques, you can create a deeper sense of realism and depth in your creations!