FBX IO: Speed up transformation animation import #104870

Thomas Barlow · 2023-09-05T19:03:56+02:00

Thomas Barlow commented

2023-09-05 19:03:56 +02:00

This patch speeds up the conversion from animated FBX lcl
translation/rotation/scale to Blender translation/rotation/scale.

An FBX file containing an armature with 65 bones and a single animation
with 1523 frames (each one keyframed) animating 47 bones (144 animated
channels in the FBX file) goes from a 1.01s import to a 0.38s import for
me with this patch. This patch should provide better baselines to
compare future performance improvements against.

Animated rotations are now converted to radians in advance using NumPy.

The non-animated matrices are now calculated once in advance and
combined into as few matrices as possible using the associative property
of matrix multiplication, reducing the amount of matrix multiplication
required to calculate the final matrix for each imported keyframe.

This patch speeds up the conversion from animated FBX lcl translation/rotation/scale to Blender translation/rotation/scale. An FBX file containing an armature with 65 bones and a single animation with 1523 frames (each one keyframed) animating 47 bones (144 animated channels in the FBX file) goes from a 1.01s import to a 0.38s import for me with this patch. This patch should provide better baselines to compare future performance improvements against. Animated rotations are now converted to radians in advance using NumPy. The non-animated matrices are now calculated once in advance and combined into as few matrices as possible using the associative property of matrix multiplication, reducing the amount of matrix multiplication required to calculate the final matrix for each imported keyframe.

Thomas Barlow added 3 commits 2023-09-05 19:03:59 +02:00

acffdf2725 Speed up _transformation_curves_gen

Precalculate the matrices that do not change each frame.

Convert animated rotation values to radians in advance with NumPy.

888ac37a7d Move pre- and post- matrices outside the hot loop

691c3d0c45 Tidy up

Thomas Barlow requested review from Bastien Montagne 2023-09-05 19:04:08 +02:00

Bastien Montagne approved these changes 2023-09-11 12:54:53 +02:00

Bastien Montagne left a comment

The changes makes sense on the general level, will trust you with the implementation details. nice improvements once again on speed.

Thomas Barlow added 3 commits 2023-09-11 13:49:06 +02:00

8bb30da036 Fix in-place modification of item.anim_compensation_matrix

56bcc06c6f Merge branch 'main' into fbx_import_anim_numpy_p1.5

f7e372e475 Increase FBX IO version

Thomas Barlow merged commit e7b1962893 into main

2023-09-11 13:53:12 +02:00

Thomas Barlow deleted branch fbx_import_anim_numpy_p1.5

2023-09-11 13:53:13 +02:00

Thomas Barlow referenced this issue from a commit

2023-09-11 13:53:13 +02:00

FBX IO: Speed up transformation animation import

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FBX IO: Speed up transformation animation import #104870