center point in camera view [duplicate]

Question

Is there a simple way in python to rotate/position a camera so that a specific point (X,Y,Z) is in the middle of the camera viewfinder in Blender 2.8?

Answer 1

1. Get the camera-object direction as a vector by subtracting the cameras location from the objects location: direction
2. Convert this vector to a look at quaternion with the vectors to_track_quat('Z', 'Y') function. This function returns a quaternion rot which points its Z in the direction of the direction vector and its Y in the direction of the global Y.
   Convert rot to a 4x4 matrix.
3. Convert the cameras location into a Translation Matrix and store it in loc.
4. Compose the new camera matrix by matrix-multiplying the loc matrix and the rot matrix and assign it to the camera matrix_world.

import bpy
import mathutils

cam = bpy.context.scene.camera
object = bpy.context.active_object

direction = cam.location - object.location

rot = direction.to_track_quat('Z', 'Y').to_matrix().to_4x4()
loc = mathutils.Matrix.Translation(cam.location)

cam.matrix_world =  loc @ rot