Tetrahedron — Georg Nees, 1969

Dissertation 1969 · pp. 156 / 158 / 171

ALGOL 60

'COMMENT' TETRA is not written out.,
'TETRA draws a tetrahedron
 of a given size'.,

SCHWARM(-120.0,120.0,-80.0,60.0,
         1.0,5.0,100,TETRA)

'FOR' I.=1 'STEP' 1 'UNTIL' K 'DO'
'  '  SCHWARM(...,TETRA)
'K.=2 : first pass = figure 16,
 second = figure 18.

This page · drawing kernel

JavaScript

function TETRA(A, B, FAKTOR) {
  // regular tetrahedron, edges
  // size FAKTOR, rotation J4,J5,J6
  rotate(unitTetra * FAKTOR);
  for (const [i, j] of EDGES) {
    LEER(A + v[i][0], B + v[i][1]);
    LINE(A + v[j][0], B + v[j][1]);
  }
}
TETRA(J2(-120, 120), J3(-80, 60), J1(1, 5));
// Reconstruction: body not in the book.

Approximate rendering. Figure 16 is the same SCHWARM call as figure 15, with TETRA in place of STAR: squares become tetrahedra; place and size stay the parameters D…N and U, V. The book never writes the body of TETRA; the live figure is a regular wireframe, oriented with JS4…JS6 so that J1…J3 still supply size and place as in the star cluster. P. 171: the first of two passes without re-seeding is figure 16, the second figure 18. Sheet 90° clockwise like the scan.