Changing Camera Axes in Eve7

Newbie
1

Hi all, I’m an undergrad researcher working on a project in Eve7. This is my first time using ROOT/Eve7 on a project, and everything’s been working smoothly so far, except I’m running into a problem with setting/changing the camera orientation. Is there a way to rotate the camera or make it so that the z axis points upwards rather than to the right? I tried to replicate the solution I saw in another thread about changing the camera axes in Eve, but it seems like it doesn’t work in Eve7. Any guidance is appreciated.

Thanks so much,
Theo

ROOT Version: 6.36.000
Platform: macOS Sequoia 15.5
Compiler: Not Provided

2

Try with TView::RotateView(), e.g.

  TView *view = gPad->GetView();
  cout<<view->GetLongitude()<<" "<<view->GetLatitude()<<" "<<view->GetPsi()<<endl;  // see current values; longitude = phi, latitude = theta
  view->RotateView(-30, 60);

If you want to rotate in psi as well (see printout from the above), you can do what is done by ROOT in the page I linked above: get the view and then manually do SetView (instead of RotateView) with psi different from zero, and also adjust the Pad as shown there too.

3

gPad and TView are not used with Eve7.
I hope @alja or @matevz can help here.

4

@jtheo @linev @matevz

Hi Theo

For the moment, there are only two camera types that can be set in REveViewer: kCameraPerspXOZ, kCameraOrthoXOY [1].

To my understanding, you need a CameraPerspXOY type. I will add this type with the other missing camera types (kCameraPerspYOZ, kCameraPerspYOZ, kCameraOrthoXOZ, kCameraOrthoZOY,kCameraOrthoXnOY, kCameraOrthoXnOZ, kCameraOrthoZnOY, kCameraOrthoZnOX)

Thank you for the report!

Alja

[1] root/graf3d/eve7/inc/ROOT/REveViewer.hxx at master · root-project/root · GitHub

1 Like
5

Thanks all so much for the quick replies. @Alja when do you think the other camera types would be available to use? No rush or anything, just curious.

Best,
Theo

6

@jtheo

I will make a PR to the main branch within this week.
Here is the commit that changes the camera direction so that the Z axis is the camera’s up axis.

Do you need this addition in a specific release?

Alja

7

@alja

Thanks for letting me know. If it could be made a part of the newest ROOT release, that would be great.

Thanks again,

Theo

8

Just for info. The pending PR is here [reve] Additional Perspective and Orthographic camera types by alja · Pull Request #19661 · root-project/root · GitHub.

1 Like