TrueType Font rendering in Java?

Question

I have made a GUI that has multiple components with it and now I need to populate those components with text.

My specifications:

• Preferably uses LWJGL (OpenGL)
• Isn't exceptionally complicated
• Doesn't use any other external libraries (bar the LWJGL library)
• Has to be fairly optimised, it will be used a lot on a very fps intensive GUI
• Has the possibility of being anti-aliased?
• Possibly have the ability to run on most major Operating Systems

How could I do this in java?

Answer 1

You have three options: Bitmap fonts, texture fonts and vector fonts.

Bitmap fonts are only useful if all you want to do is render text for a 2D GUI. However, you can't do antialiasing if you use Bitmap fonts. On the other hand, they're pretty easy to use and they're quick to render.

Texture fonts allow for antialiasing, but again they're best for 2D GUIs. If you want to render text in world space, you'll get lots of artifacts because of the texture scaling that's taking place. To use texture fonts, you have to create a texture atlas that contains an image for each character of a particular font that you want to use (usually you'll want to restrict the character set to ASCII, otherwise your texture will be too large). You can use AWT to create a rectangular image that contains all the characters you need. Then you can render a character by rendering a quad with the appropriate texture coordinates for that character. It is advisable to use a luminance alpha texture so that you can blend it with the color you want the text to be in. You can optimize this by using display lists for each character and possible for each string, but you'll run into problems with kerning etc.

Vector fonts give you the best results if you want to render your text in world space. They will give you perfect font rendering incl. kerning, but they're more expensive to render. My usual approach is to create a path (using AWT) for each string that I want to render, flatten that path and then trace it using the GLU tesselator. This will give you a bunch of triangles, triangle strips and triangle fans which you can put into a VBO for optimal performance. Then you can render that string by issuing the appropriate rendering commands for the VBO. You can optimize this further by using a display list for each string. That way, you will only have to send one command per string, but of course this will still be more expensive than the other methods.

Answer 2

I would consider using SVG, and particularly Batik for managing the fonts. I am doing quite a lot with this myself and it's somewhat of a learning curve. I would be prepared to start simply and find out what particular features you need before worrying about performance. But until you give clearer ideas I'm not sure we can help much more