Panorama?

[VladimirKalachikhin]

Is there a right way to create a panorama from a DEM file? That is, a horizontal view from the ground level?

I calculate the camera options using map.calculateCameraOptionsFromTo(), and have pitch 90 and elevation 1 in CameraOptions object, but the view is still obtained from a height, not from sea level.

{
  "center": {
    "lng": 37.348899999999986,
    "lat": 44.82560000000001
  },
  "elevation": 1,
  "zoom": 13.353102899051677,
  "pitch": 90.00000862269115,
  "bearing": -15.340999922171227
}

[HarelM]

I think you need to set clamp to ground false or something. Generally speaking, you can't move the camera inside the terrain, so that might move the camera to a different position than expected.
I think @NathanMOlson can probably help with that. You can also use the slack channel to ask questions, there's a vibrant community there.

[NathanMOlson]

I believe @HarelM is correct, you need to set centerClampedToGround = false. You can see an example here: https://maplibre.org/maplibre-gl-js/docs/examples/set-center-point-above-ground/

[VladimirKalachikhin]

enterClampedToGround = false is a bad answer.

My problem is that calculateCameraOptionsFromTo() returns a solution unsuitable for the panorama.
To get a good panorama, the center of map must be in the middle of the lower side of the viewport. Is it possible?

[VladimirKalachikhin]

Heh, sorry, I got it all wrong.
The maplibre shows the view to where, but not from where. So, it is impossible to make a panorama.

[HarelM]

There's a camerafromto method which has some calculations on where to place a camera in order to look at something, maybe you can "reverse" the math there to know how to control the camera.

[VladimirKalachikhin]

This function is called calculateCameraOptionsFromCameraLngLatAltRotation() :-)

It calculates the zoom so that, with the available width of the viewport, the view is from a given point. Exactly what I wanted above. But there was no way of guessing.

Thus, you can get a realistic view. But you can't make a smooth horizontal rotation around the viewing point.

[HarelM]

Have the "screen" rotate around the camera is indeed more trickey, but I've seen a demo somewhere doing it - i.e. rotating around a point that is not the center of the map (it was used to rotate around the top of a 3D building instead of the base of it).
So I think it's possible, might not be easy or straight forward but surly possible.

[VladimirKalachikhin]

No way to do it.
To rotate the view around the camera point, you need to change the position of the center of the map. This means you need to recalculate the entire scene.