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#!/usr/bin/env python
import sys, math
sys.path[:0] = [".."]
import pyx
from pyx import *
c = canvas.canvas()
c.stroke(path.line(0, 0, 4, 2), [deco.earrow.Large()])
t = text.text(2, 1, r"$\vec p$")
t.linealign(0.1, -2/math.sqrt(20), 4/math.sqrt(20))
c.insert(t)
c.stroke(path.line(0, 0, 1, 1), [deco.earrow.Large()])
t = text.text(0.5, 0.5, r"$\vec a$")
t.linealign(0.1, -1/math.sqrt(2), 1/math.sqrt(2))
c.insert(t)
c.stroke(path.line(-1, 3, 3, -1), [style.linestyle.dotted])
c.stroke(path.line(1, 1, 1-1/math.sqrt(2), 1+1/math.sqrt(2)), [deco.earrow.Large()])
t = text.text(1-1/math.sqrt(8), 1+1/math.sqrt(8), r"$\vec b$")
t.linealign(0.1, 1/math.sqrt(2), 1/math.sqrt(2))
c.insert(t)
c.writeEPSfile("boxalignpal")
###############################################################################
c = canvas.canvas()
c.stroke(path.line(0, 0, 4, 2), [deco.earrow.Large()])
t = text.text(2, 1, r"$\vec p$")
t.linealign(0.1, -2/math.sqrt(20), 4/math.sqrt(20))
c.insert(t)
c.stroke(path.line(0, 0, -1, 1), [deco.earrow.Large()])
t = text.text(-0.5, 0.5, r"$\vec a$")
t.linealign(0.1, -1/math.sqrt(2), -1/math.sqrt(2))
c.insert(t)
c.stroke(path.path(path.arc(0, 0, math.sqrt(2), 0, 360), path.closepath()), [style.linestyle.dotted])
c.writeEPSfile("boxalignpac")
###############################################################################
c = canvas.canvas()
c.stroke(path.line(0, 0, 4, 2), [deco.earrow.Large()])
t = text.text(2, 1, r"$\vec e$")
t.linealign(0.1, -2/math.sqrt(20), 4/math.sqrt(20))
c.insert(t)
c.stroke(path.line(0, 0, 6, 2), [deco.earrow.Large()])
t = text.text(3, 1, r"$\vec f$")
t.linealign(0.1, 2/math.sqrt(60), -6/math.sqrt(60))
c.insert(t)
c.stroke(path.line(6, 2, 4, 2), [deco.earrow.Large()])
t = text.text(5, 2, r"$\vec g$")
t.linealign(0.1, 0, 1)
c.insert(t)
c.stroke(path.line(0, 0, -1, 1), [deco.earrow.Large()])
t = text.text(-0.5, 0.5, r"$\vec a$")
t.linealign(0.1, -1/math.sqrt(2), -1/math.sqrt(2))
c.insert(t)
c.stroke(path.path(path.arc(0, 0, math.sqrt(2), 0, 360), path.closepath()), [style.linestyle.dotted])
c.stroke(path.line(0, 0, 0, math.sqrt(2)), [deco.earrow.Large()])
t = text.text(0, 1/math.sqrt(2), r"$\vec b$")
t.linealign(0.1, -1, 0)
c.insert(t)
c.writeEPSfile("boxalignlac")
###############################################################################
def drawexample(canvas, corner, linealign):
r = 1.5
canvas.stroke(path.path(path.arc(0, 0, r, 0, 360)))
phi = 0
while phi < 2 * math.pi + 1e-10:
if corner:
b = box.polygon(center=(0, 0), corners=[(0, 0), (1, 0), (0.5, math.sqrt(3)/2)])
else:
b = box.polygon(center=(0, 0), corners=[(-0.5, -math.sqrt(3)/6), (0.5, -math.sqrt(3)/6), (0, math.sqrt(3)/3)])
if linealign:
b.linealign(r, math.cos(phi), math.sin(phi))
else:
b.circlealign(r, math.cos(phi), math.sin(phi))
if round(phi / math.pi * 2 * 100) % 100:
canvas.stroke(b.path())
else:
canvas.stroke(b.path(), [color.rgb.red])
phi += math.pi / 50
d = 6
c = canvas.canvas()
sc = c.insert(canvas.canvas([trafo.translate(0, d)]))
drawexample(sc, 0, 0)
sc = c.insert(canvas.canvas([trafo.translate(d, d)]))
drawexample(sc, 0, 1)
sc = c.insert(canvas.canvas([trafo.translate(0, 0)]))
drawexample(sc, 1, 0)
sc = c.insert(canvas.canvas([trafo.translate(d, 0)]))
drawexample(sc, 1, 1)
c.text(0, 1.5*d, "align at a circle", [text.halign.center])
c.text(d, 1.5*d, "align at tangents", [text.halign.center])
c.text(-0.5*d, d, "reference point at the triangle center", [text.halign.center, trafo.rotate(90)])
c.text(-0.5*d, 0, "reference point at a triangle corner", [text.halign.center, trafo.rotate(90)])
c.writeEPSfile("boxalignexample")
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