search

brainglobe / brainrender

a python based software for visualization of neuroanatomical and morphological data.
https://brainglobe.info/documentation/brainrender/index.html
BSD 3-Clause "New" or "Revised" License
540 stars 75 forks source link

[BUG] Zoom parameters aren't applying the correct scaling #377

Open IgorTatarnikov opened 4 weeks ago

IgorTatarnikov commented 4 weeks ago

After #364 the zoom parameter doesn't provide the correct scaling when passed to the plotter.show function.

The following examples create an animation that first shows zoom=1 and then zoom=1.2 using the frontal camera.

If resetcam=False (the current behaviour):

https://github.com/user-attachments/assets/d7c51469-fa82-4cf1-957e-e7902549efa0

If resetcam=True:

https://github.com/user-attachments/assets/605c799f-78f7-474d-ad9d-754ab6a23205

I believe the resetcam=True animation is the expected behaviour.

GuillaumeLeGoc commented 18 hours ago

Hi there, I have a related bug. Previously I managed to create nice videos with the following keyframes :

anim.add_keyframe(0, camera="top", zoom=1)
anim.add_keyframe(3, camera="sagittal", zoom=0.95)
anim.add_keyframe(6, camera="frontal", zoom=1)
anim.add_keyframe(9, camera="frontal", zoom=1.2)
anim.make_video(duration=12, fps=15)

This now results in the following video :

https://github.com/user-attachments/assets/7126b36f-b3fe-431f-bdb8-9fd35e3e1525

It seems the zoom factor is applied at each frame instead of each view. The animation example seems to work because it's rather short so the zoom does not have time to make the brain very small. In my example above, setting fps to a low value (eg. 2 or 3) mitigates the problem, confirming that the zoom (in or out) is applied at each frame. As suggested I tried settings resetcam=True but I did not really know where exactly. I tried as an argument of each add_keyframe but that did not change anything, then I tried directly here : https://github.com/brainglobe/brainrender/blob/78c0426766087d79667e426af559b3a36fe20b9c/brainrender/render.py#L268

This worked and I got the expected result. Before this gets fixed, do you have an idea where I could specify this argument from a script rather than editing the source file ? I can also make a PR (if it's only a matter of settings resetcam=True by default) if you don't have time.

Cheers !