112 lines
3.7 KiB
Python
112 lines
3.7 KiB
Python
#!/usr/bin/env python3
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# Command line program to create svg apollonian circles
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# Copyright (c) 2014 Ludger Sandig
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# This file is part of apollon.
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# Apollon is free software: you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation, either version 3 of the License, or
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# (at your option) any later version.
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# Apollon is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
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# along with Apollon. If not, see <http://www.gnu.org/licenses/>.
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import math
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from fablabchemnitz_apollon import ApollonianGasket
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def ag_to_svg(circles, colors, tresh=0.00005):
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"""
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Convert a list of circles to svg, optionally color them.
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@param circles: A list of L{Circle}s
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@param colors: A L{ColorMap} object
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@param tresh: Only circles with a radius greater than the product of tresh and maximal radius are saved
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"""
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svg = []
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tresh = .000005
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print ('>>', tresh)
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# Find the biggest circle, which hopefully is the enclosing one
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# and has a negative radius because of this. Note that this does
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# not have to be the case if we picked an unlucky set of radii at
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# the start. If that was the case, we're screwed now.
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big = min(circles, key=lambda c: c.r.real)
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# Move biggest circle to front so it gets drawn first
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circles.remove(big)
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circles.insert(0, big)
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if big.r.real < 0:
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# Bounding box from biggest circle, lower left corner and two
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# times the radius as width
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corner = big.m - ( abs(big.r) + abs(big.r) * 1j )
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vbwidth = abs(big.r)*2
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width = 500 # Hardcoded!
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# Line width independent of circle size
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lw = (vbwidth/width)
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svg.append('<svg xmlns="http://www.w3.org/2000/svg" width="%f" height="%f" viewBox="%f %f %f %f">\n' % (width, width, corner.real, corner.imag, vbwidth, vbwidth))
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# Keep stroke width relative
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svg.append('<g stroke-width="%f">\n' % lw)
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# Iterate through circle list, circles with radius<radmin
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# will not be saved because they are too small for printing.
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radmin = tresh * abs(big.r)
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print(radmin)
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for c in circles:
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if abs(c.r) > radmin:
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fill = colors.color_for(abs(c.r))
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svg.append(( '<circle cx="%f" cy="%f" r="%f" fill="%s" stroke="black"/>\n' % (c.m.real, c.m.imag, abs(c.r), fill)))
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svg.append('</g>\n')
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svg.append('</svg>\n')
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return ''.join(svg)
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def impossible_combination(c1, c2, c3):
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# If any curvatures x, y, z satisfy the equation
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# x = 2*sqrt(y*z) + y + z
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# then no fourth enclosing circle can be genereated, because it
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# would be a line.
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# We need to see for c1, c2, c3 if they could be "x".
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impossible = False
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sets = [(c1,c2,c3), (c2,c3,c1), (c3,c1,c2)]
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for (x, y, z) in sets:
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if x == 2*math.sqrt(y*z) + y + z:
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impossible = True
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return impossible
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def main(c1=3.,c2=2.,c3=2.,depth=5):
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# Sanity checks
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for c in [c1, c2,c3]:
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if c == 0:
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print("Error: curvature or radius can't be 0")
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exit(1)
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if impossible_combination(c1, c2, c3):
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print("Error: no apollonian gasket possible for these curvatures")
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exit(1)
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ag = ApollonianGasket(c1, c2, c3)
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ag.generate(depth)
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# Get smallest and biggest radius
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smallest = abs(min(ag.genCircles, key=lambda c: abs(c.r.real)).r.real)
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biggest = abs(max(ag.genCircles, key=lambda c: abs(c.r.real)).r.real)
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return ag.genCircles |