Drawing and Perspective-- Ascending & Descending Planes???

[Seira Relur]

I'm taking an Advanced Drawing & Perspective class, and I'm completely confused. I'm to draw out some interior environment thumbnails using 1-pt. and 2-pt. perspectives (understood), as well as ascending and descending planes. I reviewed my textbook and these are the definitions I received and no visual examples to compare.

Ascending Planes - Flat surfaces not parallel to the ground or floor planes in which the vanishing points appear above the horizon line.

How I perceived this:


Descending Planes - Flat surfaces not parallel to the ground or floor planes; the vanishing points of descending planes fall below the horizon line.

How I perceived this:



I clarified this with my professor, and while she said this was correct, she also added "Another way to think about ascending and descending is in an ascending drawing it appears as if the buildings or objects are coming toward you and in a descending drawing it appears as if the buildings or objects are going away from you, the viewer. "

This confused me all over again; I understand things visually and she didn't provide any examples with explanations on this (this is an online class). Can someone give me some clarification with visuals, please???  

[Errol McGillivray]

Not parallel doesn't mean it has to be perpendicular. (You're showing perpendicular (nadir and zenith) planes.)

Try slopes instead. A road on a hill or a flight of stairs as seeing it moving away from you. Then if you're under a flight of stairs, it looks like it's coming towards you.

I'm not sure. We didn't cover that when I took perspective, but that seems to be the common sense that I could make out of it. I'd have to do some more studies and let you know.  

[akinmytua]

I don't know if this helps but I think of it as if I am an ant or I am flying. The perspective would be different depending on the angle. Lets say you were sitting on top of a mailbox and looking at the sidewalk. It would be very different from sitting up in a tree and looking at the sidewalk. At least that is what I think you are asking?