Is there an equation representing the visual/spatial rate of change of an object relative to an observer/human eye?
If I were to first sketch the figure of a person on a piece of paper, (without reference) how could I then draw that same figure closer or farther away consistent with their change in distance at their accurate height?
If the answer is just to keep drawing until it becomes natural, I will, but I'd like to know if there's any equation or geometric concept that could help.