Most of us don't have experience with Visual Studio, we built Codeblocks from scratch. Please explain what's that "functions highlighting", so we could add this feature at a later stage.
Also, the "keywords" tell the editor what are the reserved keywords of your language, for example, in C++ we have "for", "while", "if", etc. Codeblocks allows also to highlight your "custom" keywords. But I didn't program that feature and I don't use it, so I couldn't tell you how it works
If you want to highlight a particular type of variables, I'm afraid this isn't possible (yet). However, you can highlight ALL the user-defined variables in a different color. That's the "normal" color
I set my normal color to bold blue for PHP, and the keywords to black. This way only the function names will be highlighted in blue.
The syntax highlight feature is part of the
Scintilla editor component, perhaps you can find more info with them.