Here is an ebuild for the bmp-rootvis plugin.
Created attachment 41400 [details] The ebuild
Thank you for your report. The ebuild worked at the first try. I have removed the "inherit eutils", as this is only needed when you apply patches with epatch. The ebuild is in CVS, if you sync after two hours, you will be able to merge it.
I also updated the SRC_URI to use ${P} instead of the filename, that way you can upgrade by just copying the ebuild file.