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Butterflies!3D, Expressions, and Parenting Oh My!
Step 1: Begin by creating a new composition that uses the DV NTSC preset and set the length of the composition to 5:00. Name this composition Butterfly and press Okay.
Hint: The keyboard shortcut for creating a composition is Command+N on the Mac or Control+N on the PC.
Step 2: Create a New Solid by pressing the Command+Y key on the Mac or the Control+Y key on the PC. Name this layer Right Wing with pixels dimensions of 200 x 200. Give the wing a nice yellow color.
Step 3: Create another New Layer with the same dimensions and color, but this time name the new solid Left Wing.
Step 4: In the Switches column of the Timeline turn on the Make 3D layer switch for both of the layers.
We are going to want to rotate these makeshift wings at their corner. After Effects allows you to rotate a 3D layer based on one of the three axes (X, Y, or Z). If we want to rotate the square layer by its corner, we would have to rotate on multiple axes. This could cause some problems and be a major headache. Instead we can rotate the layers and use a Null Object as a parent for the wings.
Step 5: Add a Null Object to the scene by going to Layer>New>Null Object. Name the Null as Right Wing Null and click Okay. Make the Null Object a 3D layer as well.
Hint: The keyboard shortcut for creating a Null Object is Shift+Option+Command+Y on the Mac or Shift+Alt+Control+Y on the PC. With such a complex keyboard shortcut, I dont blame you if you want to go to the menu to add this element.
A Null Object is a nothing object, meaning it wont be rendered or seen by the camera. It is however very useful when creating a complex move like the one we are about to do.
Step 6: With the Right Wing selected in the Timeline press the R key to activate the 3D Orientation property. Change the Z axis orientation for the Right Wing layer to -45 degrees.
Step 7: By default the Anchor Point for a Null Object is in the upper left hand corner of the box that represents the Null. Realize that the Null is not actually the shape of the box, that is just how After Effects is displaying a nothing object to you. Now position the corner or the Right Wing on the Anchor Point of the Right Wing Null.
Step 8: In order for the Wing to move with the Right Wing Null it needs to be parented to the Null. Position your cursor over the Switches/Modes column in the Timeline and Click and hold the Right mouse button. This will display a floating menu. From the menu go to Panels and select Parent. This will display the Parent Column in the Timeline.
Step 9: Use the PickWhip to select the Right Wing Null as the Parent of the Right Wing. If you dont like using the PickWhip, you can select Right Wing Null from the Right Wing Parent drop down menu.
Step 10: With the Right Wing Null selected in the Timeline press the R key to open the Rotation property values for the layer. Create an initial keyframe for the Y rotation axis by clicking on the Stopwatch Icon. Leave the rotation value at 0.
Step 11: Go to frame 7 by pressing Command+G on the Mac or Control+G on the PC and entering 7 in the pop up window. Press Enter and the Timeline Indicator will move to the new location.
Step 12: Change the Y rotation axis to 60. This will create an automatic keyframe for the layer since you already turned on the create keyframe option in Step 9.
Step 13: Go to frame 15 and change the Y rotation axis back to 0. If you scrub through the Timeline, you will see you have just created a wing lap flap for the wing. Because the Right Wing is parented to the Null, it must rotate on the Null Objects Y-axis giving the illusion that the Right Wing is rotating on the corner point.
This short animation only represents a half second wing flap, yet the duration of the composition is set to 5 seconds. If you wanted to have the wing flap the entire duration of the animation you could do one of two things. The first would be to select all of the keyframes for the Right Wing Null Y rotation axis and copy and paste then through the duration of the Timeline. The second, and easier method of repeating keyframes is to use an Expression.
Step 14: With the Right Null Y rotation axis selected in the Timeline Option+Click (Alt+Click on the PC) on the Stopwatch Icon. This will open the Expression feature for this layer property. The area to enter the Expression is located work area of the Timeline. In this area enter the following Expression:
loop_out(type = "cycle", num_keyframes = 0)
This will cause After Effects to loop all of the keyframes in the property infinitely.
We now have one wing created, lets quickly set up the Left Wing.
Step 15: Add a new Null Object to the Composition. Name this Null Left Wing Null. Make this Null object a 3D layer.
Step 16: Select the Left Wing layer selected, press the R key to activate the Rotation/Orientation properties for the layer. Rotate this layer 45 degrees and align the corner with the Anchor Point of the Left Wing Null. Finally, Parent the Left Wing to the Left Wing Null.
Step 17: Instead of going through the entire process of creating keyframes for the Left Wing Null, adding expressions, etc. highlight the Y rotation axis for the Right Wing Null and press Command+C on the Mac, or Control+C on the PC to copy the keyframes and expressions for the layer.
Step 18: Press the Home key to make sure you are at the beginning of the Timeline and then highlight the Left Wing Null. Press Command+V on the Mac, or Control+V on the PC to paste the properties from the Right Wing Null to the Left Wing Null.
Step 19: If you scrub through the Timeline now, you will notice that the Left Wing Null is rotating in the wrong direction! This is easily fixed. Press the R key to open the Rotation/Orientation properties for the Left Wing Null layer. Use the advance to next keyframe arrow to move to the middle keyframe. This keyframe should read 60 degrees on the Y-axis. Change this value to -60 degrees.
Scrub through the Timeline and you should see the wings are now both flapping correctly.
Related Keywords:After Effects, schleicher, 3D, animation, motion graphics, parenting, expressions
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