(I didn't mention that I drew the above while thinking with Caspar David Friedrich's The Wreck of the Hope on my mind, mostly because I forgot but also because people sometimes look at you funny if you mention art-historical influences for quilt designs).
Anyway, with the basic concept in place, the next step was to figure out the relative widths of the strips. One option was just cutting them all to the same width and fudging the angles, but we're talking about Niece #2 here and I wanted to shoot a little higher than that. To help me get the geometries right, I used simple graphics software to overlay a more exact pattern over the original sketch.
This seemed pretty good, but I wondered if I could create a sense of depth by making the top "shard" with thinner strips. I came up with this:
I checked with N#2, and she agreed that this second version was better.
After that came the torturous application of high-school geometry, as I experimented with different strip widths. Ultimately, and despite the numbers on the above mock-up, I decided that making the vertical black-white strips 3.25 inches wide will yield the right size of blanket. That makes the stripes of the three shards, from bottom to top, 2.9, 2.3, and 1.45 inches wide, not exactly measurements that are marked on your standard quilting rulers. Cutting the fabric involved quite a bit of eyeballing, with some help from this "annotated" mockup:
At this point, I have lots of strips cut long, and a vague hope that I'll actually be able to tie all those weird angles together. Maybe it will be easy? But I totally doubt it.
At this point, I have lots of strips cut long, and a vague hope that I'll actually be able to tie all those weird angles together. Maybe it will be easy? But I totally doubt it.