Hi huanle5062,
Thanks for the video. The Axis Center is for the Object itself, not for the selected polygons.
https://help.maxon.net/us/index.html#11100
I have created a little screen-capture to show the differences, and how to center your selection axis as well.
https://www.amazon.com/clouddrive/share/Tpz5MbLdMIsGo1yhW8ViEZdxZuzNBMSUu75eDflC1sG
Since we can have a vast number of combinations by selecting partially polygons of an object, these polygons (or points or edges) selection axes will change. Sometimes we need them de-centered, and the tools have an option for that.
The Object Axis by itself is the “parent” to all points. Every single point relates to this Object Axis. Each edge refers to a pair of points, and each polygon is based on point-groups (See Structure Manager)
This project was designed by me way back in time, and yes, the interface was different back then. I’m sorry that you run into that so often. However, I’m glad you asked, so we can give a little update here. With over three thousand tutorials, it is not simple to keep up with the changes. The main philosophy seems to be to create rather new content with new ideas. I think that makes more sense, as many people have grown with us for over a decade by now. However, I understand that this can lead to frustration. My apologies.
That the object vanishes is based on clipping. I assume you are familiar with this from your comp-app. Fusion>Preferences> 3D> Far/Near Clipping.
https://help.maxon.net/us/index.html#OCAMERA-ID_GROUP_SETTINGS
I’m glad you use the Commander as a crutch to get through the tutorials despite the missing synchronicity.
Another tip for finding things in the menu, if you have gotten the tool via Commander, you can right mouse click on any parameter of that specific GUI-element and request help via right-mouse-click.
In the top line of the Help-Text is typically a hierarchy where it is, like:
Cinema 4D Program Documentation Reference Cinema 4D Basic Features Mesh Menu
Let me know if there is anything else, I’m happy to look into it.
Enjoy, stay safe, stay healthy.