Assimp FBX Import support

Issues fixed:
- Updated assimp to latest and backported fixes into godot.
- Fixed file scale being ignored from FBX file.
- Fixed bone removal
- Implemented proper armature binding
- Fixed recursion not always going through the entire path
- Implemented assimp global scaling system
- Fixed assimp global scale process to support unit conversion
- Implemented proper fbx scaling
- Fixed asserts caused by missing faces in some models which could crash
- Fixed valid bone removal
- Fixed root node being overwriten by assimp which caused data loss
- Fixed armature construction so that it works with multiple roots
- Implemented basic support for FBX standard materials
- Refactoring to improve code quality and improve function reuse.
- Simplified node creation from assimp scene into subsections: create_light, create_mesh, create_bone.
- Creating meshes is now done after hierarchy is created so that the skeleton is always available.
- Added support to assimp to support file scale in all formats which call SetFileScale.
- Many other fixes provided into assimp.

Known issues:
- FBX pivots from Maya do not currently work. (workaround: for now use blender import and export to remove pivot tracks)
- Hierarchy creates an extra node for each mesh - this was done intentionally but we intended to do a pass to remove these as they're a required node.
- When an animated mesh has not executed any animation the rest pose is wrong.

Co-authored-by: K. S. Ernest (iFire) Lee <ernest.lee@chibifire.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/thirdparty/assimp/code/PostProcessing/CalcTangentsProcess.cpp b/thirdparty/assimp/code/PostProcessing/CalcTangentsProcess.cpp
index b30f39c274..a3f7dd2557 100644
--- a/thirdparty/assimp/code/PostProcessing/CalcTangentsProcess.cpp
+++ b/thirdparty/assimp/code/PostProcessing/CalcTangentsProcess.cpp
@@ -212,7 +212,7 @@ bool CalcTangentsProcess::ProcessMesh( aiMesh* pMesh, unsigned int meshIndex)
             // project tangent and bitangent into the plane formed by the vertex' normal
             aiVector3D localTangent = tangent - meshNorm[p] * (tangent * meshNorm[p]);
             aiVector3D localBitangent = bitangent - meshNorm[p] * (bitangent * meshNorm[p]);
-            localTangent.Normalize(); localBitangent.Normalize();
+            localTangent.NormalizeSafe(); localBitangent.NormalizeSafe();
 
             // reconstruct tangent/bitangent according to normal and bitangent/tangent when it's infinite or NaN.
             bool invalid_tangent = is_special_float(localTangent.x) || is_special_float(localTangent.y) || is_special_float(localTangent.z);
@@ -220,10 +220,10 @@ bool CalcTangentsProcess::ProcessMesh( aiMesh* pMesh, unsigned int meshIndex)
             if (invalid_tangent != invalid_bitangent) {
                 if (invalid_tangent) {
                     localTangent = meshNorm[p] ^ localBitangent;
-                    localTangent.Normalize();
+                    localTangent.NormalizeSafe();
                 } else {
                     localBitangent = localTangent ^ meshNorm[p];
-                    localBitangent.Normalize();
+                    localBitangent.NormalizeSafe();
                 }
             }