Nils Kneuper 12c8469303 adjusted the images to all be created the same way, way to create them:
1) create a new grayscale image in gimp with 100x100 and 72dpi

2) fill the whole with black

3) in layer settings change the opacity to the value wanted
2007-06-15 11:07:42 +00:00
..

This directory contains the images used to assemble dialogues.  Each group of
images is named by the part before the first dash, which is a style
referenced by name in the Wesnoth UI code.

The 'transparent' images have some alpha transparency; they look like
smoked-glass overlays on the terrain or whatever else is underneath them.
The 'opaque' images are geometrically the same, but opaque.