There is another way to create transparent masks. It is uniting several layers into so called clipping mask. Transparent areas of bottom layer are converted to mask that covers all unnecessary parts of the image located on the top layer. If the bottom layer contains no transparent areas, the effect is impossible. The advantage of clipping masks is that all the overlying layers can be seen.
To create a clipping mask, at least two layers are required:
- copy a ClipArt picture to the clipboard;
- create a new document (File | New) with transparent background contents;
- create another layer (Create New Layer on Layers palette);
- insert picture from the clipboard (Ctrl+V);
- switch to the bottom transparent layer and paint any area with the brush tool;
- holding down the Alt key position the pointer over the line dividing two layers in the Layers palette (the pointer changes to two overlapping circles), and click (see pic.7).
Pic.7. Creating clipping masks
Note, that after a clipping mask is created, only the transparent areas of the bottom layer are visible. On the other hand, all the layers added to clipping mask will be visible according to the mask.
To remove a layer from a clipping mask, hold down Alt, position the pointer over the line separating two grouped layers in the Layers palette (the pointer changes to two overlapping circles), and click.
