A simplified version of the old tutorial. A viewer pointed out that setting the Transparency to Alpha, simplifies things.
The text display created in this tutorial is used in ‘creating a practice level for a simple ball game’ tutorials.
Key points –
To display text interactively a simple mesh plane is UV mapped to a bit map file of a character set of a particular font.
Mapping to the first character in the image file Blender will then map correctly to all the other characters.
A custom property must be added to the mesh plane which must be named ‘Text’.
In Edit mode in the Object Data properties, after a mesh has been unwrapped, in the Texture Face panel, you must tick ‘Text’
To see all this working the 3D Viewport, shading must be set to Textured.
You have to set up logic bricks and possibly Python scripts to update the Text property when events occur.
Source