How to enter the composition depth of a graphic? Is the composition depth value positive or negative?

Through the input of size and position, there is no positive or negative difference. In painting, photography and other artistic fields, the depth of composition is expressed by the position, size and perspective effect of objects in the picture. For example, the depth of an object in a picture is depicted by means of foreground object placement, background blurring, perspective deformation, etc. There is no positive or negative difference, and it is often expressed in a non-negative form. In composition, depth values are usually used to describe the position and distance relationship of objects, but these descriptions do not need to use positive numbers and negative numbers. In some specific application scenarios, there are also cases where the depth value can be negative, but this is usually related to the special definition of the scene. So it can be said that the depth value is generally neither positive nor negative.