Quote (card_sultan @ Jan 13 2017 03:56am)
The answer is Width Height and Depth, but x, y , z will do - z being depth which is the most important axis when referring to actual perspective.
Now look at that picture - you see the z axis, see how the railroad tracks appear to converge - but of course the dont - they are completely parallel.
But know also notice how they appear to get higher - so notice how the further away they are - the higher they get
again you know thats not true right? that are completely flat, they dont actually get higher - they appear to get higher due to perspective.
Now see the point they join up higher than the bottom - at the horizon right?
Now is that the real horizon or the horizon you think is real but is only there due to perspective?
Card, do you actually understand how perspective works? In a physical sense? Yeah, tracks appear to converge and appear to rise up to eye level. But why? The problem here is that you see a phenomenon and you make faulty assumptions based on your observations, simply because you don't actually understand the phenomenon itself.
We lose resolution at greater distances, so things appear closer and closer together. However, they will ALWAYS maintain their relative position to each other. In other words, the left train track will never appear to cross over the right track. And objects that are above will never appear under the objects that are below. Perspective view cannot make the sun partially sink into the ground, it is optically impossible. There can be no horizon on a flat earth, it defies geometry. If you have an unobstructed line of sight to an object, you will always see it. It may be too small for your eyes to resolve the detail, but it will still be in your field of view.
Light travels in straight lines, so the geometry of optics for a problem like this is very, very simple. If you set up your model and you can draw a straight line from your eye to the potion of the sun that you can't see (the part that's below the ground), then you should be able to see it and your model is wrong.
Another way to convince yourself is binoculars. If you look at your converging tracks through binoculars, you will see them in greater resolution and see that they are still parallel. However, the sun will still be just as "setting", with the exact same percentage of the sun below the ground. If half of the sun has set, no optics no matter how powerful will allow you to see the half that's disappeared. Of course this isn't a good idea to experiment on with the sun (since you'll damage your eyes), but can be easily verified with a setting (or rising) moon. Even a telescope that will allow you to visually explore the moon like you are standing on its surface still won't be able to show you the portion of it that you can't see with your naked eye. Clearly 'perspective' has nothing to do with this.