

  
                             3D Foundation Classes



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



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      Table of Contents
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           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 object instance?

              What is a DEFINE?

              What is TXE?

              How to debug a TXE file?

              What is a sector?

              What is a portal?

              How can I get the last version or more information?



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      FAQ
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          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 reseted when the first is increased.

          It count the beta release or minor version.
          
          The third is reseted when the second is changed. Count a patch:

          small code alterations, a feature inclusion, bugfix,...



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


          No, normaly they are from functions that implement features
          
          not present in the current target platform
          
          (like sockets for DOS/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 doc/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.

          Portal clipping is one of the possible visualization
          
          methods in 3DFC.



          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 declaration 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 DEFINE?


          Is a model that can be instanciated. DEFINE is the model,

          OBJECT is a copy of one or more DEFINES. Objects are used

          to populate the scenery.

          Refer doc/3dfc.txt for more info.



          Q: What is TXE?


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

          With it is possible create sceneries.

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



          Q: How to debug a TXE file?


          This is hard, not all possible errors are reported by the

          system. But there is some hints:
          
          set the compiling flag COMP_SHOWLOADING to 2, file config.h.
          
          Use the example TestTXE to test the bugged TXE file

          (run: make extesttxe). Use /* and */ to ignore some suspect

          code - remarks are balanced: /* /* foo */ bar */ is possible,

          and the efect is make 'foo bar' ignored.



          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 a 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, ...?


          See file readme.txt
