Plot text with ascii extended characters

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What steps will reproduce the problem?
1. Add title to a plot using ascii extended characters.
2. Display the plot. 

What is the expected output? What do you see instead?
The expected output is the title with the ascii extended characters and instead 
you get the title without any extended characters.

What version of the product are you using? On what operating system?
Current version on a windows XP.

Please provide any additional information below.
I made a change the to code and it seems to work.
I included a casting to a unsigned char in every call to glutBitmapCharacter 
("static_cast<unsigned char>(s[i])").
By doing this glutBitmapCharacter sees characters in the range expected (0 to 
255 not negative). 

Original issue reported on code.google.com by [email protected] on 5 Sep 2014 at 1:56