Firstly, I would like to say, preferably, support the developers of TTFText and FlyingText3D on the Asset Store for beautiful glorious real 3D text.
If you want a quick “cheat” you can do the following (from After Effects technique eg. Greyscale Gorrila’s tutorial). Below requires some understanding of scripting, though of course if you ask questions perhaps various people can answer it here.
The most interesting thing is that in most modern 2.5D/3D programs if you “extrude” a 2.5D element by duplicating along the Z-axis it becomes ~solid~!
//2.5D "Extrude"!
var theText: GameObject = GameObject.Find("TextHolder: ToExtrude"); // this has "Text Mesh" component...
var theTempGameObject : GameObject;
//This makes the "thickness"
for (var t: float; t<15; t++)
{
theTempGameObject = GameObject.Instantiate(theText,Vector3(0,0,t/80),Quaternion.Euler(0,180,0));
theTempGameObject.renderer.material.color = new Color(0.2,0.2,0.2,1);
}
//This makes the "front face"
theTempGameObject = GameObject.Instantiate(theText,Vector3(0,0,0.2),Quaternion.Euler(0,180,0));
theTempGameObject.renderer.material.color = new Color(1,1,1,1);