How to make a fish swim

[Mike Clasby]

There are lots of ways to do what you want. Try a few of these and get back if you want more.

Probably the quickest and easiest for a wave flapping fish:
1. Animate you fish layer across the screen, at the beginning of the timeline Drag the fish to just off the left edge of the screen, click the Position (P reveals position) stopwatch then move down the timeline and then drag the fish to just off the right side of the screen, a new keyframe will be automatically set since you already clicked the stopwatch setting that first keyframe.

Now let’s precompose so we can add the Wave Warp Effect to the whole screen, not just the fish layer. Layer>Precompose (check move all attributes). Note: Don’t get lost if AE opens that new comp because you had that box checked.

Now to that precomped layer add Distort>Wave Warp and tweak to taste, your fish will wiggle his way across the screen.

If you want a rigid fish on a wavy path:
Make your rigid fish move from left to right like you did in step one above.

Now to draw a wiggly motion path, Window>Motion Sketch and with your mouse (a Wacom Pen is better) draw a wiggly line, left to right. Done.

To get a smoother wavy path, you could animate one cycle of the fishes anchor point, then put a cycle expression on it (easier than it sounds).

“A” reveals the fishes Anchor Point (the point around which animation happen, best seen with rotation, ie, moving the anchor point moves the swivel point). Anyway, at the beginning of the timeline (Home) set a keyframe for the fish’s Anchor Point (click the Anchor Point stopwatch), and to move down the timeline four frames, hit the Page Down key four times (you choose how many times depending on how fast you want your wavy motion), then with your mouse drag the y value of your anchor point (blue number on the right) to the right, increasing the value by 10 or so, Eight more of Page Down and drag that y to the left, decrease the y by 20, then four more Page Down and drag it back to the starting amount. The fish should move on a wavy path (1 cycle over those 16 frames).

OK, to get this animation to repeat your going to use an expression, no sweat.

First copy the expression first (select the one line expression below, Ctrl C), then Alt Click the Anchor Point Stop Watch, then Paste in the expression:

loopOut ( “cycle”, 0)

You should now have a fish on a smooth continuous path.

OK, you could combine the two methods and have a flag wavy fish on a wavy path… or not.

If you got lost on some of the basics of After Effect Animation techniques, look at Andrew Kramer’s tut, After Effects 101, click on his head at the top of the main page and scroll down, it’s near the bottom.

To get the details of the loop expression, click on Dan Ebbert’s head (the Expression Master) and scroll down to Animating a Walk Cycle, there are four or five loop styles and Dan has an aep to illustrate them.

Note: You can also get your wavy motion with Displacement Mapping, click on Aharon’s head (Army Command Cap) and scroll down to the Three Displacement tuts>

Good luck.

[John Baum]

Teaching him how to “fish” 🙂

[Winfreebot]

Thanks a bunch, guys.

I’m going through all the options you gave me yikesmikes and I’m getting some pretty decent results I appreciate all the help.