Uncomfortable

2016-03-31 15:52

Here's a dumb sketch to illustrate the point: https://i.imgur.com/nY6q15q.jpg

Basically, whenever you have any sort of pivot, hinge, or other element that causes two parts of the same object to sit at different orientations from each other, you're adding vanishing points. As I mentioned in the lesson, each vanishing point governs a set of parallel lines. The vast majority of objects are made up of far more than just three sets of parallel lines, and therefore will have more than three vanishing points.

Remember that in this count, you have to include all of your vanishing points. While you might draw a simple box in 1 point perspective, it's still made up of three sets of parallel lines, and therefore still has 3 vanishing "points" though in that situation, two of them exist at infinity and cannot be represented on the page (as I discuss in the notes on rotation).

In the example sketch I linked above, you see four vanishing points, but there also exists one other that governs the vertical lines, all of which are parallel.

Beyond just pivots and rotation, you'll see that there are little flaps that come out on the front and back, and hang at a 45 degree angle from the horizontals around them. Those too are governed by entirely separate vanishing points that were not drawn in. If I had drawn in those VPs, they would be sitting above the horizon.

Uncomfortable

2016-04-05 02:13

Oh wow, that's dense. I'm going to have to take some time to really read over that in detail, but thanks for sharing!

Uncomfortable

2016-04-17 17:04

The approach we're using - that is, estimating things approximately, instead of plotting out everything and applying all of the rules of perspective exactly, certainly does have its shortcomings. For instance, with our approach there's no exact way to draw a perfect cube. Distances in our scenes are interpreted in relation to one another - you can technically draw any box (within reason) and claim it to be a perfect cube, after which point every other form you draw must conform to that.

Knowing how much smaller to make your boxes based on how far they are is, again, a matter of considering how the boxes relate to one another. If you look at the drawing on the right of this image (which I did as a critique for someone else a while back), you can see how I've pointed out how each box's size relates to one another. It's all about how far away they are from the viewer, and which ones are closer or further. Those in the corners are going to be the furthest away, (think about the Pythagorean Theorem - c^2 = a^2 + b^2, where c is the distance of a corner box - let's say top-right for example's sake - from the viewer, while a is the distance to the top-center box and b is the distance to the left-middle box).

You make a couple arbitrary assertions of your own (my smallest box is going to be this small, my biggest box is going to be this big) and every other size in between falls in.

Now, despite this perhaps overly technical explanation, rather than fussing over all of this, I encourage people not to overthink it. There's a lot going on, and because of that your first several attempts are going to be terrible failures with inconsistent proportions. Through attempting the exercise multiple times (even after the lesson is marked as complete, which is only to say you're going in the right direction, not that you've reached your destination) you'll subconsciously develop a sense of 3D space and how those forms relate to one another, while only keeping a shadow of the concepts I've mentioned above in the back of your mind.

Uncomfortable

2016-05-15 20:34

You should definitely mark out where you want your lines to start/end (just like in the ghosting exercise). The only thing you not doing on the paper is drawing lines that go all the way back to the vanishing point - that's what you're visualizing in your mind's eye.