Expressions Without the Math : Adobe After Effects Tutorial

CreativeCOW Adobe After Effects Tutorial

Doug Bassett
Washington DC

Article Focus:
Recently Doug Bassett was working on a promo and tried to follow Fred Lewis' connection scripts but couldn't follow the math. In this article, Doug demonstrates a new approach which uses expressions but without the math...and he finished the promo in a minimal amount of time.

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Project file: .sit

Project file: .zip

Create a new solid and call it object 1 and position it somewhere off center.

With the layer selected, hit the "P" key to reveal the position parameter.

Option click the stop watch to reveal the expression for position area.

Type .wiggle (5,25) after the word position in the selected area and hit the "RETURN" key on the numeric key pad

Duplicate this layer 3 more times to have 4 layers and offset them from each other so you can see them all.

Create a new comp size solid and name it "connect 1 to 2". Set this layer to best quality.

Apply the beam effect to the connect 1 to 2 layer.

Effect > Render > Beam
Set the length to 100%
Set the Start to 3 and end to 10.

Twirl down the starting and ending points of the Beam effect.

Option click the stop watches for both start and end parameters.

Drag the start pick whip to the position property of "object 1" and the end pick whip to the position property of "object 2" and hit the "ENTER" key on the numeric keypad.

Close the "connect 1 to 2" and the "object 1" layers, duplicate the "connect 1 to 2" layer and rename it to "connect 2 to 3".

Hit command+"D" two more times to duplicate the layers.
Rename them "connect 3 to 4" and "connect 4 to 1".

Shift click to select Objects 2,3,4 and hit the "P" key to reveal the position properties.

Select layers 5,6,7 which are the "connect 2 to 3", "connect 3 to 4", "connect 4 to 1", and hit the "U" key to reveal the beam effect properties.

Start by twirling down the arrows for the start and end points of the "connect 2 to 3" layer to reveal the pick whip for these parameters.

Drag the pick whip "START" to the position property of "Object 2" and the "END" pick whip to the position of "Object 3", and hit the "ENTER" key on the numeric key pad.

Repeat this step of pick whipping for "connect 3 to 4" and "connect 4 to 1"

For additional movement you can now go back and key frame position for the object layers.

Have fun!

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