FBX: since we have more and more options differing between new 7.4 and legacy 6.1, add a draw() func (temp, to be removed once we get rid of 6.1).

This addresses the following issue: by default, when you export in a non-Blender orientation
(matching your target import app), your imported root objects have additional rotation,
since correction matrix is applied to object transform.

This patch addresses this by actually baking the correction matrix at data level, when possible
(currently only works for meshes).

Note this makes spaces/matrices handling rather complex, so this is considered an experimental
option currently, might break in some cases.

Work based on patch T39251 by Jens Restemeier, thanks.

What to expect:
* Static export of empties, meshes, cameras and lamps, as well as materials and (image!) textures should work OK.
  There are a few advanced topics still TODO regarding meshes and mat/tex, though.
* Custom properties from objects/meshes/lamps/cameras/armatures/bones/materials/textures are exported too (only simple ones, ints/floats/strings).
* Armature export: this needs testing by people having *native* FBX aplications, linking between bones and meshes seems to work, but I have doubts about bones orientations.
* Animation: still a complete TODO.

Note that old FBX ASCII 6.1 exporter is still available (top dropdown in exporter's UI).

Many thanks to Campbell, which did the ground work of decyphering FBX binary format and wrote basic code to read/write it.

Using a bit more flexible way to handle those values (range now from 10^-18 (20) to 10^2 (0) frames). Not sure we shouldn't rather get rid of such "magic" value and let user set frame threshold directly, though!

use diffuse alpha channel if no other alpha channel set, hidden option to treat all alpa as decals (no shadow and z offset)

- binary fbx files only
- version 7.1 or newer
- meshes, uvs, materials, textures
- support for blender-internal and cycles materials (depends on engine selected)

note - yes, this cant load fbx files exported by blender, for that to work we would need to update the exporter.

make addons blender versions consistent

finished

from John Brown (jcbdigger) 
patch file:
    fbx_xna_unified-2011-08-02a_jcbdigger.patch


Option not to export Default Take

fbx_xna_unified-2011-08-01b_jcbdigger.patch

Only part of this patch has been applied (just the changes to the operator).

from John Brown (jcbdigger)

The patch has been modified, some of the changes I rather see applied as separate patches.

This commit adds/changes:
- Option to export XNA compatible armature rotations.
- Option not to export mesh edges.
- Always export armatures as 'Limb' type.
- dont write default cameras or camera switch when cameras are disabled.
- fix for (harmless) error where armature connections were written out twice.

- remove/comment unused variables
- remove unused imports
- fixed some bugs using incorrect variables

- fbx default use_selected to False

also option to export lamps was missing.

Added option for smoothing export - Face/Edge/Off.