Archive for November 29th, 2019

GCMC Radial Text

The Tektronix Circuit Computer needs text along radial lines:

Tek CC - original RC arrow layout
Tek CC – original RC arrow layout

Fortunately, this doesn’t require nearly as much effort as the text-on-arcs code, because GCMC includes functions to rotate paths around the origin:

return rotate_xy(TextPath,Angle) + CenterPt;

The only trick is figuring out how to handle the justification, given the overall path length:

  local pl = TextPath[-1].x;

  local ji = (Justify == TEXT_LEFT)     ? 0mm :
             (Justify == TEXT_CENTERED) ? -pl/2 :
             (Justify == TEXT_RIGHT)    ? -pl :

A testcase showed it worked:

Radial text testcase
Radial text testcase

With that in hand, I took the liberty of slightly simplifying the original Tek layout:

Tek CC - radial text example
Tek CC – radial text example

If lives depended on it, one could duplicate the Tek layout, but they don’t and I didn’t. Fancy typography isn’t a GCMC thing.

And, yeah, laser printing is way crisper than a pen drawing.

The GCMC source code as a GitHub Gist:


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