I have currently created some animated wings, I want these wings to have a drop shadow over the background image. I was trying to figure out how to render the wings with a shadow without anything else in the background, I was thinking that I could render the frames in png with transparency, then import into flash over the background image where the shadow would show up. I say png because of the alpha transparency.
The only other way I could think of was to have the Environment map of the image that i want behind the wings to show up on the render, but I am not sure how to make the wings show a drop shadow on the environment map, plus the file size would be bigger because I would be rendering the background (environment map) on every frame with along with the wings which would result in a bigger file size. The background would be static so it seems pointless to render the background over and over during the wing animation. Does anyone have a solution or suggestion? thanks for any help,