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         Inertia real-time 3D rendering engine trouble shooting guide
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This document discusses some common mistakes that can be made when you're using
Inertia. If you experience any problems, consult this guide first before
writing us a bug-report. If there's a problem that you think should be included
here, feel free to contact us.


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Problem : I get a general protection fault whenever I assign a texture surface
          type to an object.

Cause   : You haven't loaded a texture or you haven't assigned one to this
          object. This problem will only occurs in Protected Mode. In Real Mode,
          you'll get a rubbish texture.



Problem : I get a general protection fault whenever I assign phong-shading to
          an object.

Cause   : You haven't created a phong-map or you haven't assigned one to this
          object. This problem will only occurs in Protected Mode. In Real Mode,
          you'll get a totally messed up intensity distribution.



Problem : I did load a texture and I did create a phong-map. But I still get
          a general protection fault.

Cause   : Be sure to check the results of the Load..... and MakePhongMap
          functions. If they detect an error (Out of memory, file not found
          etc.), they don't halt the program, but merely return an error value.
          Check the Inertia.ref file for error codes.

Problem : I loaded all the textures and objects properly, but I get nothing
          on the screen.

Cause   : The object does not have texture coordinates. Add textures coordinates
          with the TMAP program or make sure the original object has texture
          coordinates.

Problem : The computer hangs whenever I run my program. I am using the SMC
          polygon fillers and Real Mode.

Cause   : You forgot to reassemble the polygon fillers. The SMC fillers write
          directly to the code segment, and in protected mode this has an
          offset of 8 bytes. In Real Mode, there's no such offset. The
          DPMI compiler directive in PDEFINES.INC takes care of the correct
          compilation of the fillers.

Problem : I get miscellaneous General Protection faults when using protected
          mode.

Cause   : BP7's *terrible* memory allocation system only lets you allocate
          64K-1 bytes of memory. With the 256x256 textures, you need that
          extra byte. All efforts have been made to minimize this including
          using a DPMI call to manually extend the segment limit an extra
          byte.

Problem : I have a hole in my head.

Cause   : You've been shot at.
