Graphic3d_Group::Text(...) are obsolete, AddText() should be used instead of these methods.
Graphic3d_Text is a new class for parameters necessary to fill OpenGl_Text. All parameters of Graphic3d_Group::Text() are moved into this class.
OpenGl_TextParam is removed, these fields were moved into Graphic3d_Text.
OpenGl_Text constructors/Init with OpenGl_TextParam parameter were removed. Constructor with Graphic3d_Text should be used instead of it.
Using OpenGl_Text Init() with OpenGl_TextParam should be now replaced on two cases. The first case is setting values into Graphic3d_Text and the second case is calling Reset() after. As example, look at modification in OpenGl_FrameStatsPrs.