Two approaches I can think of:
2D:
Duplicate your Wings layer to create a shadow layer. Use the Fill and Blur effects to make it shadow-like, offset it, and parent it to the main Wings layer so it follows any movement you make. Duplicate your Surface layer to use as a matte, and parent it to the Surface layer so it too follows any movement you make. Stack your layers like this, from top to bottom: Wings, Surface Matte, Wings Shadow, Surface. Set Wings Shadow to be matted by Surface Matte’s alpha.
3D:
Make these layers 3D. Set the light and the Wings layer to cast shadows, and set the Surface layer to receive shadows. (Additionally, set their “Accept Lights” properties to off if you don’t want the layers shaded by the lights.) Separate them in Z-space and position them and the light to taste.
Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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