September 25, 2009 Leave a comment
The Wiggler, one of the features that first drew me to After Effects all those years ago, has by far the best name for an option in any piece of software! But its ability to generate random values for anything in your animation is still a most powerful necessity, and when this can be achieved through simple scripting, it adds a whole new weapon to your arsenal of animation tools and techniques. Let’s create a really stunning title sequence for a program called “It’s a Bit of an Animal” with just four keyframes and a little Expression magic.
The specs for this project are an NTSC square-pixel composition (720×540), 29.97 frames per second, 4 seconds long, with a background color of black. Some of the effects we’re using here are only available in the Professional version of After Effects.
[For a QuickTime preview of this project, go to www.layersmagazine.com/magazine-downloads.]
STEP 1 Import PSD; Duplicate 3D Layers
Import a texture image from Photoshop that’s 768 pixels square. This will serve as one of the walls to the animal cage we’ll create. We’ll need six walls for the cube arranged perfectly in 3D space-easy using Digital Anarchy’s 3D Assistants that ship with After Effects. Drag the texture into the Timeline at 0 seconds, and make it 3D by clicking in the blank box under the cube switch. Press Command-D (PC: Control-D) five times to duplicate the layer, giving us the six layers we need. Then, in the Comp window, switch to Custom View 1 instead of the Active Camera.
STEP 2 Create 3D Cube; Remove Front Face
With all six layers selected, go to Window>Box Creator Lite (make sure you’ve installed the 3D Assistant plug-ins from the AE Installer CD), select Fit Box to Layers, and click Apply. You should now see a cube shape, and if you hit C to access the Orbit Camera tool, you can rotate around the cube in the comp window. Now, in the Timeline, turn off the visibility of the first layer to remove the front of the cube so we can see inside it. Return to the Active Camera view.
STEP 3 Add, Position, and Rotate 3D Camera
Go to Layer>New>Camera and from the Camera dialog, choose a preset of 28mm, then click OK. You should see a little more of the cube now because of a greater perspective. We’re going to animate this camera to be very “hand-held,” so we need to turn off its auto orientation value by going to Layer>Transform>Auto Orient, choosing Off, and clicking OK. Hit P to access the camera’s Position, and key in 630, 90, and -560 for the X, Y and Z axes. Then, hit R for Rotation, and key in 350, 340, and 356 for the Orientation property.
STEP 4 Import Illustrator Titles; Place in Cage
Double-click in the Project window to access the Import dialog and bring in a layered Illustrator file containing the titles. Be sure to choose Composition – Cropped Layers from the Import As sub-option. Open the newly created comp, select all the layers, copy the layers, then switch to the main comp, and paste them in. Click the 3D Layer icon for one layer to make them all 3D, then drag only the red and green arrows in the comp window to position the titles’ X and Y axes to the lower right (dragging the arrows on one layer will move them all together).
STEP 5 Add Position Expression
Select one of the title layers, hit P for Position, and hold down the Option key (PC: Alt key) while clicking on the Position Stopwatch to add an Expression. We need to use a simple Wiggle script to randomly animate the position but constrain it to one axis. To do this, we need a variable. Key in “steve = wiggle(3,350);”. This establishes a wiggle of 350-pixel movement, three times per second, packaged up inside a variable and given a name-in this case my name. But the script is not complete, as it now wiggles on all three axes.
STEP 6 Finish Expression
Press Return at the end of the first line of script, and key in “[position, position, steve]“. This tells AE to keep the original position values for the X and Y axes (0 and 1) and to use the Steve Wiggle value on the Z axis (2). Press Enter to OK the script and then preview the animation-perfect random motion along one axis! Select the two lines of script and copy them. Select the other title layers one at a time, Option-click (PC: Alt-click) their Position Stopwatch, and paste in the same script. AE now creates new random values for every layer.
STEP 7 Animate Camera with Keyframes and Script
At 0 seconds, select the camera and show its Position and Orientation values. Click their Stopwatch icons to add keyframes, and then go to 4 seconds. Change Position to 20, 530, and -560 and Orientation to 16, 25, and 353. A preview now shows a nice smooth animation across the cage. Maybe the camera should shake realistically? Hold down Option (PC: Alt), click on the camera’s Orientation Stopwatch, and enter this script: “wiggle(3,5);”. Preview again. This rotates the camera randomly by 5� three times per second.
STEP 8 Add Light; Parent to Camera
Now, at 0 seconds, go to Layer>New>Light. Choose Spot, Intensity 110%, Cast Shadows On, 55% Darkness, 10 px Diffusion, and click OK. Again, go to Layer>Transform>Auto Orient and select Off. Let’s attach the light to the camera: Control-click (PC: Right-click) on the Source Name column in the Timeline, go to Columns, and choose Parent. Drag the small @ symbol next to the Light’s Parent option and point it at the Camera layer. Now show the Light’s Position values and change them to 0, 0, and -65. Looking through Custom View 1, you can see the light attached just above the camera.
STEP 9 Wiggle Light Intensity; Activate Shadows
To make the light flicker, let’s use that same Wiggle script again. Twirl down the Light’s options, Option-click (PC: Alt-click) on the Intensity Stopwatch, and key in “wiggle(10,50);”to randomly animate the intensity 10 times per second by up to 50% in either direction. Now select the title layers, hit A twice to access their 3D properties, and next to Casts Shadows, click to turn them all on. A preview should now show the flickering light, as well as shadows being projected onto the cage’s walls.
STEP 10 Add 3D Smoke/Dust Layer
If you have a movie render of some slowly moving smoke, use it now; if not, create a new solid layer and use AE’s Fractal Noise effect to create some. Now, bring the layer into the comp at 0 seconds, make it 3D, scale it to the edges of the cell, position it on the Y axis to just touch the bottom, and then position it on the Z axis to -360, just in front of the camera. Looking through Custom View 1, notice that the layer has a hard edge and needs to blend into the scene better.
STEP 11 Use Linear Wipe Transitions
Go to Effect>Transition>Linear Wipe, and in the Effect Controls window, change the Transition Complete value to 5% and the Feather to 40. This softens the smoke on the left side of the cage. Hit Command-D (PC: Control-D) to duplicate the effect and change the Wipe Angle to -90� to affect the right side. Duplicate the effect again, and a Wipe Angle at 0� affects the bottom. Finally, duplicate again, set the Wipe Angle to +180�, Completion to 25%, and Feather to 140, and the top of the smoke softly fades in.
STEP 12 Create Volumetric Smoke
Click the Switches/Modes button at the bottom of the Timeline to switch to Modes and set the smoke layer’s blending Mode to Screen to drop out the darkest pixels, leaving soft white smoke. Preview now through the active camera, and it’s looking great. But the smoke doesn’t have depth. Here’s a great trick for creating 3D volumetric smoke in AE: Deselect the layer, select it again (to avoid duplicating another effect), and duplicate it twice to make three layers, all currently in the same position on the Z axis.
STEP 13 Offset Smoke Layers
Access the Position values for the two duplicated layers, and change their Z axis values to -260 and -160 respectively, putting 100 pixels between each of the smoke layers. If you click the Solo icon for these layers in the Timeline and preview, you’ll see smoke now that truly looks 3D and dense. From certain camera angles, however, there’s a pattern repetition. To fix that easily, select the middle one of the three layers, access its Rotation value, and change the Y axis to 180�. Preview again and the problem’s solved.
STEP 14 Create Cage Door; Motion Blur Effects
Turn off the Solo icons and turn the visibility back on for the first texture layer (the cage front). Quickly turn this into a cage door by going to Effect>Render>Grid. Set the Border to 10 and the Color to gray. Then, add Effect>Blur & Sharpen>Fast Blur and set Blurriness to 5 pixels. Remember to hit A twice for the layer and turn Casts Shadows to On to see the grid shadow on the back wall. Finally, turn on Motion Blur for all the layers and render your finished, very cool, and realistic title sequence-all courtesy of a little command called Wiggle.