03-31-2015, 05:11 AM
hey man, that illustration is looking great!
I'll try to explain that perspective stuff. You can for the most part get away with putting 2 pt perspective vanishing points arbitrarily and corners will still look like they are 90 degrees, within a certain margin of error. What Norling is saying in that chapter though, is if you put them too close together or too far apart corners start to look warped and not at 90 degrees anymore, and squares start to look like diamonds.
I warped this image below of a giant chessboard - in the top image, horizon line sits where we expect, there is distant horizon that you might be able to just see, it's a chessboard so we know it's made up of squares, and they look like they are squares, all the corners look like they are at 90 degrees to one another.
In the second image, I warped in the vanishing points, horizon line is in the same place I just cropped out the top of the image - our brain still tells us it's squares, because we recognise it as a chessboard but it looks very warped and turns into that diamond shape he talks about.
Similar warping happens when they are too far apart. The Scott Robertson book goes into detail with how to calculate VP's so that corners are exactly 90 degrees, and what portion of the zone you can draw in before stuff starts to look warped (called the Cone of Vision), but important thing to remember is that care and forethought is needed when placing vanishing points to avoid this warping. EDIT And good rule of thumb is to space them very wide to avoid the diamond shape warping. If you look at a birds eye view of something, it is so so far from the horizon line, if you try to draw lines to it it would go so far outside the page. It still looks ok because the VP's are spaced so wide.
You don't get this warping in 1pt perspective, only in 2 / 3 pt +.
Here is another example, something I drew a while back, I had the VP's too close together so instead of a building with 90 degree corners, it starts to look warped and more diamond shaped:
Hope that helps!
I'll try to explain that perspective stuff. You can for the most part get away with putting 2 pt perspective vanishing points arbitrarily and corners will still look like they are 90 degrees, within a certain margin of error. What Norling is saying in that chapter though, is if you put them too close together or too far apart corners start to look warped and not at 90 degrees anymore, and squares start to look like diamonds.
I warped this image below of a giant chessboard - in the top image, horizon line sits where we expect, there is distant horizon that you might be able to just see, it's a chessboard so we know it's made up of squares, and they look like they are squares, all the corners look like they are at 90 degrees to one another.
In the second image, I warped in the vanishing points, horizon line is in the same place I just cropped out the top of the image - our brain still tells us it's squares, because we recognise it as a chessboard but it looks very warped and turns into that diamond shape he talks about.
Similar warping happens when they are too far apart. The Scott Robertson book goes into detail with how to calculate VP's so that corners are exactly 90 degrees, and what portion of the zone you can draw in before stuff starts to look warped (called the Cone of Vision), but important thing to remember is that care and forethought is needed when placing vanishing points to avoid this warping. EDIT And good rule of thumb is to space them very wide to avoid the diamond shape warping. If you look at a birds eye view of something, it is so so far from the horizon line, if you try to draw lines to it it would go so far outside the page. It still looks ok because the VP's are spaced so wide.
You don't get this warping in 1pt perspective, only in 2 / 3 pt +.
Here is another example, something I drew a while back, I had the VP's too close together so instead of a building with 90 degree corners, it starts to look warped and more diamond shaped:
Hope that helps!