Reflection mapping(planar) how to place camera

Hello! I am looking on how to place a camera for planar reflection mapping. That means for render-to-texture for planar surfaces as ground. Can anyone, please, help me out here?

I found the script:

    cam = scene.cameras['ReflectionCamera']
    act_cam = scene.cameras["Camera"]    
    cam.worldPosition = act_cam.worldPosition
    cam.worldPosition.z = -cam.worldPosition.z
    cam.localOrientation = act_cam.localOrientation
    rotation = cam.worldOrientation.to_euler()
    rotation[0] = -rotation[0] + 135
    rotation[1] = rotation[1]
    rotation[2] = rotation[2]
    rotFinal = rotation.to_matrix()
    cam.worldOrientation = rotFinal

Where cam is camera used for reflections and act_cam is player view cam. In material I use view mapping and invert scale in Y. It works fine, except the reflections looks like apart from it’s caster. It appears that object in scene is flying.

What could cause this and how may I fix this?