Pictorial depth cues: a new slant

The main focus of this work was the representation of surface orientation based on pictorial cues. In all the experiments discussed in this paper, the lines, the texture, and the surface were first drawn frontally and then slanted. It was determined that pictorial cues can support an accurate perception of the spatial orientation of a planar surface. Based on the observations, it was inferred that accurate slant perception was limited to the local surface area and was not necessarily maintained in register with the global map of depth. It was surmised that an observer's knowledge of the absolute position of the plane is quite loose for disjoint surfaces. This could solely account for many of the discrepancies found in the literature on slant perception.