I would like to explain about "2-ply shapes technology". (Image44.jpg)
It is a strong way to construct perspective views that changes view when vanishing point is moved.
It is used to the red roof of above theme; the color of the underside is dark blue.
In the image "Image44.jpg" below, 2 shapes are placed just in the same location.
2 shapes have exactly the same size.
When you move the vanishing point, the view changes and the color changes rose to green or green to color rose.
When the green shape is visible, the rose shape is invisible. When rose is visible, green is invisible.
If you combine z-order of the shape with this technology, perspective views can be more realistic.
When you move vanishing point a shape at the most front, it can be expected to be moved backward than other shapes.
Above Visio drawing "perspective Drawing House 4.vsd" is modified and replaced.
The fence surrounding the 2 red-roofed houses are improved using this technology.
Then the perspective view can is more realistic, when you move vanishing point.