+from __future__ import absolute_import
+__copyright__ = "Copyright (C) 2013 David Braam - Released under terms of the AGPLv3 License"
+
+import math
+import numpy
+
+class Path(object):
+ LINE = 0
+ ARC = 1
+ CURVE = 2
+
+ def __init__(self, x, y, matrix=numpy.matrix(numpy.identity(3, numpy.float64))):
+ self._matrix = matrix
+ self._startPoint = complex(x, y)
+ self._points = []
+ self._isClosed = False
+
+ def addLineTo(self, x, y):
+ self._points.append({'type': Path.LINE, 'p': complex(x, y)})
+
+ def addArcTo(self, x, y, rot, rx, ry, large, sweep):
+ self._points.append({
+ 'type': Path.ARC,
+ 'p': complex(x, y),
+ 'rot': rot,
+ 'radius': complex(rx, ry),
+ 'large': large,
+ 'sweep': sweep
+ })
+
+ def addCurveTo(self, x, y, cp1x, cp1y, cp2x, cp2y):
+ self._points.append({
+ 'type': Path.CURVE,
+ 'p': complex(x, y),
+ 'cp1': complex(cp1x, cp1y),
+ 'cp2': complex(cp2x, cp2y)
+ })
+
+ def isClosed(self):
+ return self._isClosed
+
+ def checkClosed(self):
+ if abs(self._points[-1]['p'] - self._startPoint) < 0.001:
+ self._isClosed = True
+
+ def closePath(self):
+ self._points.append({'type': Path.LINE, 'p': self._startPoint})
+ self._isClosed = True
+
+ def getPoints(self, accuracy = 1):
+ pointList = [self._m(self._startPoint)]
+ p1 = self._startPoint
+ for p in self._points:
+ if p['type'] == Path.LINE:
+ p1 = p['p']
+ pointList.append(self._m(p1))
+ elif p['type'] == Path.ARC:
+ p2 = p['p']
+ rot = math.radians(p['rot'])
+ r = p['radius']
+
+ #http://www.w3.org/TR/SVG/implnote.html#ArcConversionEndpointToCenter
+ diff = (p1 - p2) / 2
+ p1alt = diff #TODO: apply rot
+ p2alt = -diff #TODO: apply rot
+ rx2 = r.real*r.real
+ ry2 = r.imag*r.imag
+ x1alt2 = p1alt.real*p1alt.real
+ y1alt2 = p1alt.imag*p1alt.imag
+
+ f = x1alt2 / rx2 + y1alt2 / ry2
+ if f >= 1.0:
+ r *= math.sqrt(f+0.000001)
+ rx2 = r.real*r.real
+ ry2 = r.imag*r.imag
+
+ f = math.sqrt((rx2*ry2 - rx2*y1alt2 - ry2*x1alt2) / (rx2*y1alt2+ry2*x1alt2))
+ if p['large'] == p['sweep']:
+ f = -f
+ cAlt = f * complex(r.real*p1alt.imag/r.imag, -r.imag*p1alt.real/r.real)
+
+ c = cAlt + (p1 + p2) / 2 #TODO: apply rot
+
+ a1 = math.atan2((p1alt.imag - cAlt.imag) / r.imag, (p1alt.real - cAlt.real) / r.real)
+ a2 = math.atan2((p2alt.imag - cAlt.imag) / r.imag, (p2alt.real - cAlt.real) / r.real)
+
+ large = abs(a2 - a1) > math.pi
+ if large != p['large']:
+ if a1 < a2:
+ a1 += math.pi * 2
+ else:
+ a2 += math.pi * 2
+
+ pCenter = self._m(c + complex(math.cos(a1 + 0.5*(a2-a1)) * r.real, math.sin(a1 + 0.5*(a2-a1)) * r.imag))
+ dist = abs(pCenter - self._m(p1)) + abs(pCenter - self._m(p2))
+ segments = int(dist / accuracy) + 1
+ for n in xrange(1, segments):
+ pointList.append(self._m(c + complex(math.cos(a1 + n*(a2-a1)/segments) * r.real, math.sin(a1 + n*(a2-a1)/segments) * r.imag)))
+
+ pointList.append(self._m(p2))
+ p1 = p2
+ elif p['type'] == Path.CURVE:
+ p1_ = self._m(p1)
+ p2 = self._m(p['p'])
+ cp1 = self._m(p['cp1'])
+ cp2 = self._m(p['cp2'])
+
+ pCenter = p1_*0.5*0.5*0.5 + cp1*3.0*0.5*0.5*0.5 + cp2*3.0*0.5*0.5*0.5 + p2*0.5*0.5*0.5
+ dist = abs(pCenter - p1_) + abs(pCenter - p2)
+ segments = int(dist / accuracy) + 1
+ for n in xrange(1, segments):
+ f = n / float(segments)
+ g = 1.0-f
+ point = p1_*g*g*g + cp1*3.0*g*g*f + cp2*3.0*g*f*f + p2*f*f*f
+ pointList.append(point)
+
+ pointList.append(p2)
+ p1 = p['p']
+
+ return pointList
+
+ #getSVGPath returns an SVG path string. Ths path string is not perfect when matrix transformations are involved.
+ def getSVGPath(self):
+ p0 = self._m(self._startPoint)
+ ret = 'M %f %f ' % (p0.real, p0.imag)
+ for p in self._points:
+ if p['type'] == Path.LINE:
+ p0 = self._m(p['p'])
+ ret += 'L %f %f' % (p0.real, p0.imag)
+ elif p['type'] == Path.ARC:
+ p0 = self._m(p['p'])
+ radius = p['radius']
+ ret += 'A %f %f 0 %d %d %f %f' % (radius.real, radius.imag, 1 if p['large'] else 0, 1 if p['sweep'] else 0, p0.real, p0.imag)
+ elif p['type'] == Path.CURVE:
+ p0 = self._m(p['p'])
+ cp1 = self._m(p['cp1'])
+ cp2 = self._m(p['cp2'])
+ ret += 'C %f %f %f %f %f %f' % (cp1.real, cp1.imag, cp2.real, cp2.imag, p0.real, p0.imag)
+
+ return ret
+
+ def _m(self, p):
+ tmp = numpy.matrix([p.real, p.imag, 1], numpy.float64) * self._matrix
+ return complex(tmp[0,0], tmp[0,1])
+
+def saveAsHtml(paths, filename):
+ f = open(filename, "w")
+
+ posMax = complex(-1000, -1000)
+ posMin = complex( 1000, 1000)
+ for path in paths.paths:
+ points = path.getPoints()
+ for p in points:
+ if p.real > posMax.real:
+ posMax = complex(p.real, posMax.imag)
+ if p.imag > posMax.imag:
+ posMax = complex(posMax.real, p.imag)
+ if p.real < posMin.real:
+ posMin = complex(p.real, posMin.imag)
+ if p.imag < posMin.imag:
+ posMin = complex(posMin.real, p.imag)
+
+ f.write("<!DOCTYPE html><html><body>\n")
+ f.write("<svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" style='width:%dpx;height:%dpx'>\n" % ((posMax - posMin).real, (posMax - posMin).imag))
+ f.write("<g fill-rule='evenodd' style=\"fill: gray; stroke:black;stroke-width:2\">\n")
+ f.write("<path d=\"")
+ for path in paths.paths:
+ points = path.getPoints()
+ f.write("M %f %f " % (points[0].real - posMin.real, points[0].imag - posMin.imag))
+ for point in points[1:]:
+ f.write("L %f %f " % (point.real - posMin.real, point.imag - posMin.imag))
+ f.write("\"/>")
+ f.write("</g>\n")
+
+ f.write("<g style=\"fill: none; stroke:red;stroke-width:1\">\n")
+ f.write("<path d=\"")
+ for path in paths.paths:
+ f.write(path.getSVGPath())
+ f.write("\"/>")
+ f.write("</g>\n")
+
+ f.write("</svg>\n")
+ f.write("</body></html>")
+ f.close()