How to add the Cloud Filter to Custom Shapes?

Question

Hello:                                                                                                Level: Newbie    OS: Windows 7 64bit    Ps CS6
I am trying to make a sun. I used the elliptical marquee and was able to add the filter > render > coulds w/no problem
However, when I draw a custom shape and try to use the cloud filter it fills the whole layer not just the shape.
I've tried several things but nothing has worked.
Also, a box pops up that says the layer must be rasterized before using the cloud filter and then it fills the whole canvas/layer.
Any ideas? Thank you for your time

Answer 1

Photoshop filters operate on raster images (i.e. pixels) only. A couple of ways to get the necessary raster from a Shape Layer:
1. Rasterize the SL, permanently converting it to a regular pixels layer (although you could keep a hidden copy of the SL in case you wanted to return to it).
2. Convert the SL to a Smart Object which non-destructively encapsulates the SL and provides a raster representation on which filters can operate. This is advantageous in that you can edit the contained Shape Layer at any time, you can non-destructively transform (e.g. stretch or warp) the SO as many times as you want, and filters can be attached as non-destructive re-editable Smart Filters.
For Clouds to be visible in only the existing pixels and not the empty region of a layer, make a mask for the layer: target the layer, Ctrl-click on its thumbnail to get a marquee of its pixels then click the Add Mask button at bottom of Layers panel. That's what I did below, but the mask could have been used as a Smart Filters mask which you can see as a white thumbnail.