What is algebraic effect of transforms in Adobe After Effects Keyframe Data file?
Have you tried using after effects? You can get a demo, it will give you an idea of the metaphor behind it.

The position of a layer is the position of its anchor point in the comp space. The anchor point is expressed in terms of the layer space and is the point that the layer rotates around and scales from. By default the anchor point of a layer is its center. In both layer space and comp space the origin [0,0] is the top left, and increasing values move the point to the right and down. E.g. for a 1920x1080 comp / layer the point [1920,1080] is the bottom right.