image shadow from space to planet

[pyreflos]

I want to project the silhouette of a spacecraft across the surface of a planet and the clouds above it. The easiest thing to do is import an .obj file, put it between the planet & the sun, and hit render. Is there a way to map an image to a card or a plane instead? It's a lot faster to make an interesting silhouette, save it as a .png with transparency, and paste it as a material than it is to build a 3d model & import it. I'm sort of lost here.

[Oshyan]

Yep, you can do that. Add a Card object, then open its Default Shader that will be connected to its Shader input by default. Load your main image in Colour Image, then load your alpha/opacity map on the Opacity tab to get transparency. Finally, resize, position, and orient your card to cast the shadow the correct direction and you're done.

Attached is a very simple proof of concept using some random images on my HD and a small card. You'd need to resize and reposition the card to get the effect you want.

- Oshyan

[pyreflos]

Thanks! That works a heck of a lot better than the image shader/alpha effects I kept trying to use!