Should I prevent the canvas to be re rendered or persist the camera position

[roievil]

Hello,

I am building a react 3DM viewer of a parametric model, I have a canvas along with a form with controls such as sliders where the user can modify the geometry of the model.
I am using orbitcontrol, and I am having problems with the camera position : when the geometry changes the canvas is re-rendered and the user actions such as panning of zooming are lost.

Should I prevent the canvas to be re-rendered or find a way to persist the camera position? and how?

Here is a sand box, I have not included the form but you can simulate the geometry change by clicking on the change geometry button.

https://codesandbox.io/s/elastic-fire-bugbe?file=/src/components/GeometryDisplay.tsx

Also I updated the mesh part of my '3dm to threejs' converter to use BufferGeometry but did not find a way yet to convert the quad faces hence the missing faces on the display, but I am thinking that I will deal with this problem at geometry generation stage.

Thank you for any help !

Olivier

[drcmda]

i dont understand the question. what does re-rendering the canvas mean? why is something lost? in react components don't unmount if they don't need to, nothing will be lost unless you unmount components. im not sure, but do you unmount the entire canvas on a geometry change? changing geometry and orbit controls should have nothing to do with one another.

you can use cameras and controls from the drei lib btw, i see you have lots of code just for these basics.

[roievil]

Hello,

Thank you for your quick answer, maybe re render is not the correct term.
The behaviour I am referring to is that when the user interacts with the canvas, zooming, panning etc, if the geometry changes (or even if he scrolls outside of the canvas i've just noticed) there is a 'camera jerk' in the canvas window, the view of the model suddenly changes. And if I have the devtools of chrome on the canvas border is briefly highlighted, which indicates that the canvas is being rendered, right?

What I need is that the geometry updates, without a change at the camera level.

As for your advice on the drei lib thank you I am checking this out, I wrote most of the code one year ago, I did not see this at the time.

Olivier

[roievil]

Hello, I updated my code using Drei and 3dmLoader the issue seems to be resolved as when I load another 3dm the camera position stays the same only the geometry changes.

Here is the updated sandBox : https://codesandbox.io/s/elastic-fire-bugbe?file=/src/components/Test3DMLoader.js

Thank you,

Olivier