I've finally gotten through 250 boxes, almost through Lesson 4 (I actually completed these on Boxing Day, ironically).

I made a lot of realisations when doing this. I sort of have a logical method in my head to do this.

I've been doing these like warm-ups though by now I feel like I've done every possible combination of box I can do, was really trying to come up with different ones. I drew these from my arm, though I have found that for one or two boxes I had to use my wrist/elbow (but sort of treating the pen as a pendulum moving back into a place perpendicular to the drawing rarely fails or overshoots, so for smaller awkward angles I learnt that as a new skill).

Only some boxes I dotted because I was sort of building up imaginining the lines and dots in my mind's eye, which I think was very beneficial, it's like some sort of 3D-sudoku puzzle but with lines instead of numbers.

My process was as follows:

1. If the box's corner is facing me, I draw the 3 edges of its corner, to define where the vanishing points go to. If not, I draw a closer plane and a further plane and connect them.

2. When I draw the first parallel line to a vanishing point, I make it arbitrary and make no rule for it but try to think in coordination to the original parallel line how the box vanishes on say the downward axis.

3. I then try to connect these lines, making the first plane.

4. I do the same for the other external plane that feels most perpendicular to this (in terms of 3D space). I think in terms of the other side, it must have a common horizon/eye line so I make sure the perpendicular lines pinch to the the same horizon line. I sort of base this on how much it is overall converging.

5. I try define the final external plane (in the case when the point is towards me, by thinking how they converge to the same point based on the existent two parallel lines on that side (I sort of imagine a big V, possibly beyond where I can draw).

6. I then do the internal lines, by making sure if a) a line is close to an existent line, I make it more parallel, if more close to one line than another, I think in terms of the 2D angle and try to "interpolate" mentally (I get this idea from LERPing in mathematics/programming) and it always seems to check out when I do this. That's why I say I think it as more a logical process and for me I think it's the best and fastest. Another thing, I think in terms of like a "rake" as all converging lines, will, based on distance from each other, have a common heading, so I am thinking in like heading vectors and interpolation. Least I hope that is a good way, I hope to see critique on my method!

I feel like even later on I failed a little I'm not sure why but may be it's correct actually, but sometimes one axis can be sort of all-parallel when the other isn't. And that kind of makes say the top and the bottom converge differently. I've noticed others have done this, and looking at somethings in real life it seems like it is the case. It kind of makes sense because if something is vanishing mostly to the side of you, it's kind of almost like it's completely facing you, so say the floor and ceiling might not seem to actually converge to a point. But as much as that seems correct, it also seems wrong which is pretty confusing. In general I can just avoid these boxes though, I don't think I'll be needing them, but still these things are interesting even if a bit boggling illusion-wise.

Also sometimes it made sense if something got narrower if I imagine it approaching towards me, if I think in the sense of looking into the sky with my head rotated at an imaginary box in say the far side of your vision. I wonder then if it's allowable sometimes for convergence to seem to narrow onwards?

I haven't bothered to shade these, because I felt that you can sort of make a weak box more convincing by confirming to the viewer this way. Instead, for my later boxes I made myself a rule of making the sides that were going to be most close the boldest, and close corners semi-bold, with the furthest thinnest. These boxes seem the most convincing to me, and really helped me check the perspective lines as well as I could remember which corners/edges were closest. The faces that would be shaded, would be the faces that are sandwiched between the bold and semi-bold lines. Note that not all of the boxes with the stronger bold on them were correct because I was kind of working out the best way to convey this before I worked this out. Closer lines being bold is something I found out from someone else and yet I definitely think the innermost lines should be less bold, as Uncomfortable's videos have said.