[Record] How does Blender export geometry nodes as FBX with animation

origin:

In order to realize the animation of origami, first use the geometric node to make the animation in the way of key frame in blender

Then it took a day to find out how to make the keyframe of this geometric node into an fbx that can be exported, because this animation is used in Unity.

• Geometry nodes are a unique organizational form of Blender, and there is no way to export them by normal means
• The same unique organizational form includes simulated animation and other abnormal key frames. This method may work, but I haven't tried it.

After a series of rummaging, I found this [7 minutes to learn and export FBX with animation practical skills [Blender3.1]] https://www.bilibili.com/video/BV16e4y1q7Vh/?share_source=copy_web&vd_source=4f29756994d7a81d15efe55ce16fcf61

• Convert to shape key to frame, and the key frame of shape key can be recorded by fbx and can be exported directly
• The shape key only records the position of each vertex, so the shape key always contains the vertices of all objects.
• Therefore, the exported fbx file is very large, and it takes a long time to import it into Unity. I am trying to solve this problem. If there is progress, I will post it later.

---

solution:

1. First, make a copy and export the abc file.
   Note that one of the purposes of checking the subdivision option
   is to preserve the subdivision (as mentioned in the video), but I think the most important purpose for me is to apply all modifiers While preserving animation (no keyframe animation when geometry node modifier is applied)
   

2. Re-import this abc file
   Note that there is a sequence modifier here

3. Use this abc model to export the mdd file.
   If you don't have this mdd file, you can find the plug-in application under preference
   

What is an MDD file?
MDD files mostly belong to IBM's SPSS Statistics/Data collection. The MDD file extension is used by the Point Oven plug-in as a 3D image data file.
Primary use: The Point Oven plug-in is used to pass vertex and F-curve information between modeling applications. The MDD file extension is used by the Point Oven plugin to store baked vertex information for each animation frame in a particular mesh. MDD files allow exchanging vertex mesh positions/deformations between applications that support the Point Oven plugin. Since MDD files contain baked vertex information instead of animation curves and motion data, the numbers in these files can be very high, depending on mesh size and frame count.

4. Click on the model and import its mdd file, delete the sequence modifier of the abc file
   

5. Export fbx file with this model
   
   

can