The bounds of an asset created from layer or layer group are the whole area occupied by the pixels in the layer or layer group. This is how the underlying framework Adobe Generator works. We are investigating the feasibility of changing this behaviour. If you would like it changed, please let us know here!
If you would like to restrict it to the document bound, apply a layer mask that will clip layers and layer groups that extend beyond the document bounds.
In Generator I can export assets with surrounding transparent pixels by applying a layer mask to them, however in Export Assets the mask is ignored.
We are using Adobe Generator so this should not happen. Can you send me your PSD so we can investigate? manian at adobe.com
I for one would like to have the option to automatically crop to the document size. This feature is not very useful if I have to make a mask for EVERY layer. I think it's redundant to have to make a mask when you already have the document to "crop" your image. This makes working with smart object a pain and it is the recommended workflow by Adobe, so why not at least give the option to crop to document size in the Extract Assets panel?
Yes, you are right! We wanted to maintain consistency with Adobe Generator but I understand expectations are different when using Generator vs using Extract Assets. We are hoping to get this in the next major release for Extract Assets.
While you're at it, it would be nice to be able to put a bunch of images in a layer group, put on mask on that group and be applied to all layers within it. Right now, if you try this, it will extract to the size of the layer uncropped. If I can't see it in my layout, why would I want to see it in my extracted images?
I agree with JeffArdoise on this one - From my experimenting with the tutorial, the extract assumes that the image has already been cropped to the correct proportions. This kind of defeats the point of working out layouts if you already have to figure out the size of the image before adding to layout documents.
My example is a single page website - so my layout document is very tall. My images (all placed embedded) are positioned, and cropped accordingly by applying a layer mask. The extract produces my cropped image, but it is placed within my layout document proportions, not the actual cropped image size. A jpeg that should be say 1280x800 is actually 1280x6000!
The concept is great, but for me a mute point unless it can detect layer masks!
(unless of course I have missed something)
You can actually have the image cropped to the size of the mask, but the mask as to be applied to the layer itself. That's why it is tedious when you have multple images with the same cropping that you put in a layer group, and expect to have the layer cropped to the layer group mask. Right now, it doesn't allow it to be cropped.
For the time being, I made an applescript that calls an actions that go through all layers and layers in layer groups (2 levels), and makes a mask of the document size on all of the layers. It's not perfect, but it's a workaround for now.
Wanted to point out something I noticed that was not mentioned in this thread. After experimenting with Extract Assets myself, it seemed like a layer mask will indeed crop a layer but only if it is a LINKED layer mask. An UNLINKED layer mask does not crop the layer, you get the surrounding transparent pixels in the extracted asset. I very often keep my layer masks unlinked when I am cropping raster smart objects because you want to be able to drag the image around easily. I had to keep reminding myself to go back and make sure they were all linked before extracting the assets.
Haven't experimented much with masking groups and Extract Assets but dragging a layer mask onto another layer while holding down the option key is a pretty quick way to copy the same mask to multiple layers.