

  
                             3D Foundation Classes



                               *** F. A. Q. ***



     -------------------
      Table of Contents
     -------------------



           FAQ

              Why use 3 numbers for version control, example: v0.3.1?

              While compiling I see some warnings, any problem?

              Why the documentation and sources are full of english errors?

              Why, in TXE polygon attributes, the collision detection flag has

                 plan collision detection and polygon collition detection?
              
              What is a portal engine?
              
              What is an instance?

              What is a object model?

              What is TXE?

              What is a sector?

              What is a portal?

              How can I get the last version or more information?



     -----
      FAQ
     -----



          Q: Why use 3 numbers for version control, example: v0.3.1?

          
          The first (here is 0) is subjective. After many big changes it's

          increased.
          
          The second is never reseted when the first is increased.

          It count the changes in header files (function or variables
          
          declarations).
          
          The last is reseted to 0 when the second is increased. It count

          the number of changes in implementation files (the ".cc" files),
          
          or in documentation, makefiles, ... the rest.



          Q: While compiling I see some warnings, any problem?


          No, normaly they are from functions that implement features
          
          not present in the target platform (like sockets for DJGPP).



          Q: Why the documentation and sources are full of english errors?


          Because my english is not very good. I'm making many revisions to

          avoid this bugs, if you find one, tell me, pleace.



          Q: Why, in TXE polygon attributes, the collision detection flag has

          plan collision detection and polygon collition detection?


          For optimization. Plan collision detection is faster than polygon

          collision detection. In true the polygon collision detection make

          the plan collision detection and other tests. See docs/notes.txt

          for more information.



          Q: What is a portal engine?


          Is an visualization system based on polygon clipping to do
          
          invisible surface removal. See docs/notes.txt for more information.



          Q: What is an object instance?


          Is an object that can be viewed and manipulated by the engine.
          
          Is similar as a copy of a it's source model.
          
          Thinking in C++: the object model
          
          is a C++ class declaratiion and the object instance is one C++
          
          object (instanciated by the class). The source polygon mesh
          
          (between other things), are defined by a object model.

          This model is copyed to the instance during the
          
          instanciation process.



          Q: What is a object model?


          Is a model that can be instanciated. TXE is a language that can be
          
          used to declare the models and create instances. Is possible create

          instances during run-time.



          Q: What is TXE?


          "Text with Scenery Elements" is the 3DFC engine data language.

          With it is possible declare scenery data.

          See docs/txe-spec.txt for more info.



          Q: What is a sector?


          Is a convex polyedron. For a portal engine is the scenery unit.

          See docs/notes.txt for more information.

          
          
          Q: What is a portal?


          Is a polygon with an special attibute: it's a link between two
          
          sectors. Each sector have a set of polygons, portal polygons
          
          are not simple polygons, they are passages to adjacent
          
          sectors. Portals are usefull in creation of concave

          scenerys, because the sectors must the convex.

          See docs/notes.txt for more information.



          Q: How can I get the last version, more information,
          
             talk about the engine, ...?


          You have two ways:
          
          E-mail me: lebe@aton.inf.ufrgs.br

          Visit my homepage in: www.geocities.com/SiliconValley/Bay/1704
