design/boxalign.py

   1 #!/usr/bin/env python
   2 import sys, math
   3 sys.path[:0] = [".."]
   4 from pyx import *
   5
   6 c = canvas.canvas()
   7 t = c.insert(tex.tex())
   8 c.stroke(path.line(0, 0, 4, 2), canvas.earrow.Large)
   9 graph.textbox(t, r"$\vec p$").linealign(0.1, -2/math.sqrt(20), 4/math.sqrt(20)).printtext(2, 1)
  10 c.stroke(path.line(0, 0, 1, 1), canvas.earrow.Large)
  11 graph.textbox(t, r"$\vec a$").linealign(0.1, -1/math.sqrt(2), 1/math.sqrt(2)).printtext(0.5, 0.5)
  12 c.stroke(path.line(-1, 3, 3, -1), canvas.linestyle.dotted)
  13 c.stroke(path.line(1, 1, 1-1/math.sqrt(2), 1+1/math.sqrt(2)), canvas.earrow.Large)
  14 graph.textbox(t, r"$\vec b$").linealign(0.1, 1/math.sqrt(2), 1/math.sqrt(2)).printtext(1-1/math.sqrt(8), 1+1/math.sqrt(8))
  15 c.writetofile("boxalignpal")
  16
  17 ###############################################################################
  18
  19 c = canvas.canvas()
  20 t = c.insert(tex.tex())
  21 c.stroke(path.line(0, 0, 4, 2), canvas.earrow.Large)
  22 graph.textbox(t, r"$\vec p$").linealign(0.1, -2/math.sqrt(20), 4/math.sqrt(20)).printtext(2, 1)
  23 c.stroke(path.line(0, 0, -1, 1), canvas.earrow.Large)
  24 graph.textbox(t, r"$\vec a$").linealign(0.1, -1/math.sqrt(2), -1/math.sqrt(2)).printtext(-0.5, 0.5)
  25 c.stroke(path.path(path.arc(0, 0, math.sqrt(2), 0, 360), path.closepath()), canvas.linestyle.dotted)
  26 c.writetofile("boxalignpac")
  27
  28 ###############################################################################
  29
  30 c = canvas.canvas()
  31 t = c.insert(tex.tex())
  32 c.stroke(path.line(0, 0, 4, 2), canvas.earrow.Large)
  33 graph.textbox(t, r"$\vec e$").linealign(0.1, -2/math.sqrt(20), 4/math.sqrt(20)).printtext(2, 1)
  34 c.stroke(path.line(0, 0, 6, 2), canvas.earrow.Large)
  35 graph.textbox(t, r"$\vec f$").linealign(0.1, 2/math.sqrt(60), -6/math.sqrt(60)).printtext(3, 1)
  36 c.stroke(path.line(6, 2, 4, 2), canvas.earrow.Large)
  37 graph.textbox(t, r"$\vec g$").linealign(0.1, 0, 1).printtext(5, 2)
  38 c.stroke(path.line(0, 0, -1, 1), canvas.earrow.Large)
  39 graph.textbox(t, r"$\vec a$").linealign(0.1, -1/math.sqrt(2), -1/math.sqrt(2)).printtext(-0.5, 0.5)
  40 c.stroke(path.path(path.arc(0, 0, math.sqrt(2), 0, 360), path.closepath()), canvas.linestyle.dotted)
  41 c.stroke(path.line(0, 0, 0, math.sqrt(2)), canvas.earrow.Large)
  42 graph.textbox(t, r"$\vec b$").linealign(0.1, -1, 0).printtext(0, 1/math.sqrt(2))
  43 c.writetofile("boxalignlac")
  44
  45 ###############################################################################
  46
  47 def drawexample(canvas, corner, linealign):
  48     if corner:
  49         b = graph.alignbox((0, 0), (0, 0), (1, 0), (0.5, math.sqrt(3)/2))
  50     else:
  51         b = graph.alignbox((0.5, math.sqrt(3)/6), (0, 0), (1, 0), (0.5, math.sqrt(3)/2))
  52     r = 1.5
  53     canvas.stroke(path.path(path.arc(0, 0, r, 0, 360)))
  54     phi = 0
  55     while phi < 2 * math.pi + 1e-10:
  56         if linealign:
  57             b.linealign(r, math.cos(phi), math.sin(phi))
  58         else:
  59             b.circlealign(r, math.cos(phi), math.sin(phi))
  60         if round(phi / math.pi * 2 * 100) % 100:
  61             canvas.stroke(b.path())
  62         else:
  63             canvas.stroke(b.path(), color.rgb.red)
  64         phi += math.pi / 50
  65
  66 d = 6
  67 c = canvas.canvas()
  68 sc = c.insert(canvas.canvas(trafo.translation(0, d)))
  69 drawexample(sc, 0, 0)
  70 sc = c.insert(canvas.canvas(trafo.translation(d, d)))
  71 drawexample(sc, 0, 1)
  72 sc = c.insert(canvas.canvas(trafo.translation(0, 0)))
  73 drawexample(sc, 1, 0)
  74 sc = c.insert(canvas.canvas(trafo.translation(d, 0)))
  75 drawexample(sc, 1, 1)
  76 t = c.insert(tex.tex())
  77 t.text(0, 1.5*d, "align at a circle", tex.halign.center)
  78 t.text(d, 1.5*d, "align at tangents", tex.halign.center)
  79 t.text(-0.5*d, d, "reference point at the triangle center", tex.halign.center, tex.direction.vertical)
  80 t.text(-0.5*d, 0, "reference point at a triangle corner", tex.halign.center, tex.direction.vertical)
  81 c.writetofile("boxalignexample")
  82
  83