Example of repair of 'submarin.ttf for use as rendered font by FTGL
submarin.ttf , font with bad lower-case 's'
Submarine.ttf , repaired font
Contents of Readme.txt
15. September 2006
RE: bugfix of submarin.ttf font (yellow submarine)
There is a problem with the standard submarin.ttf file as downloaded from
the web. All letters seem to be okay except the lower-case 's', for which
the generating spline is counterclockwise rather than clockwise. This
was problematic for use by FTGL renderer, which uses the FreeType library
and its own code to render text in OpenGL.
For the texture, bitmap and pixmap modes, the rendering is okay.
For the "outline" and "extruded" rendering modes, however, the
backwards ordering of the spline creates grotesque artifacts.
(May screw up the polygon font as well.)
I used the open-source fontforge program under Cygwin to edit and correct
the spline ordering of the 's' character.
1. Double-click on the 's' to bring up the edit window.
2. Click on the small green arrow showing the direction of the spline.
3. Go to the "element" menu and choose the "clockwise" command.
4. Close the window, save the font (as a .sfd file)
5. Use the Generate Font command and select TrueType if not already selected.
6. Do not change the size of the font to be a power of two.
7. The file is now fixed.
The submarin.ttf file has been replaced therefore with Submarine.ttf, which
has the corrected letter 's'.