Display of mouse position and scroll bar

When performing image operations, such as clicking the mouse or moving the mouse, the view coordinates are used. That is, the point in onlbuttondown (uint nflags, cpoint point) or onmousemove (uint nflags, cpoint point) is used.View coordinates. HoweverCompositionWhich of the following is required?Document coordinatesIn the case of a scroll bar, the document coordinate is equal to the view coordinate plus the scroll bar position.

That is to sayView coordinates are used for image operations and document coordinates are used for data processing..