Element: layer.alpha
Element: layer.alphanumeric
The alpha transparency for layer. All graphics on this layer are rendered transparent so that underlying graphics are visible. An alpha value is in the range 0 through 1, 1 for fully opaque and 0 for fully transparent (basically making the graphic primitive invisible).
If the graphic primitives on the layer themselves have an alpha transparency defined, then this transparency is applied cumulatively.
The value of this element can be redefined.
The alpha transparency of new layers is 1 by default.