Useful Expressions IV

Color Wheel by Marcus Geduld

This expression creates a color wheel with harmonious (matching) colors.

Create a small square solid (maybe 50pix by 50pix) of any color and move it near the top of the comp. Move its Anchor Point so that it's in the center of the comp (as if the solid was the number twelve on a clock and its Anchor Point was the center of the clock). Apply the Fill effect (render category) to the solid. Rename the solid "Base Color."

Duplicate the Solid. (The dup should be directly above the original in the Timeline layer stack. Don't move it in the comp window!) and rename the dup "Color Stop."

Add the following expression to the dup's Rotation property:

 degreeStop = 30; thisComp.layer(thisLayer,+1).rotation + degreeStop; 

Add the following expression to the dup's Color property (a property of the Fill Effect, which should also be applied to the dup, since you applied it to the original before you duplicated it):

 hueOffsetDegree = 30; layerBelowColor=thisComp.layer(thisLayer,+1).effect("Fill")("Color"); layerBelowHsl = rgbToHsl(layerBelowColor); layerBelowHue = layerBelowHsl[0]; layerBelowHueDegree = layerBelowHue * 360; thisLayerHueDegree = layerBelowHueDegree + hueOffsetDegree; thisLayerHue = thisLayerHueDegree / 360; thisLayerHsl = [thisLayerHue,1,.5,1] hslToRgb(thisLayerHsl); 

Finally, duplicate this layer (the dup) ten times, which should give you a total of twelve layers .

Try adjusting the Fill Color of the original layer ("Base Color"). The colors of all the other layers should change automatically.

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