index c89d771ec57beb99aca70f68cfb2670e890ddbfb..8f8a811dc0d94d905ba4c51874241e80ac2be173 100644 (file)
#!/usr/bin/env python
'''
Copyright (C) 2006 Jean-Francois Barraud, barraud@math.univ-lille1.fr
+Copyright (C) 2010 Alvin Penner, penner@vaxxine.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
yMax = max(yMax,pt[1])
return xmin,xMax,ymin,yMax
+def refinedBBox(path):
+ xmin,xMax,ymin,yMax = path[0][0][1][0],path[0][0][1][0],path[0][0][1][1],path[0][0][1][1]
+ for pathcomp in path:
+ for i in range(1, len(pathcomp)):
+ cmin, cmax = cubicExtrema(pathcomp[i-1][1][0], pathcomp[i-1][2][0], pathcomp[i][0][0], pathcomp[i][1][0])
+ xmin = min(xmin, cmin)
+ xMax = max(xMax, cmax)
+ cmin, cmax = cubicExtrema(pathcomp[i-1][1][1], pathcomp[i-1][2][1], pathcomp[i][0][1], pathcomp[i][1][1])
+ ymin = min(ymin, cmin)
+ yMax = max(yMax, cmax)
+ return xmin,xMax,ymin,yMax
+
+def cubicExtrema(y0, y1, y2, y3):
+ cmin = min(y0, y3)
+ cmax = max(y0, y3)
+ d1 = y1 - y0
+ d2 = y2 - y1
+ d3 = y3 - y2
+ if (d1 - 2*d2 + d3):
+ if (d2*d2 > d1*d3):
+ t = (d1 - d2 + math.sqrt(d2*d2 - d1*d3))/(d1 - 2*d2 + d3)
+ if (t > 0) and (t < 1):
+ y = y0*(1-t)*(1-t)*(1-t) + 3*y1*t*(1-t)*(1-t) + 3*y2*t*t*(1-t) + y3*t*t*t
+ cmin = min(cmin, y)
+ cmax = max(cmax, y)
+ t = (d1 - d2 - math.sqrt(d2*d2 - d1*d3))/(d1 - 2*d2 + d3)
+ if (t > 0) and (t < 1):
+ y = y0*(1-t)*(1-t)*(1-t) + 3*y1*t*(1-t)*(1-t) + 3*y2*t*t*(1-t) + y3*t*t*t
+ cmin = min(cmin, y)
+ cmax = max(cmax, y)
+ elif (d3 - d1):
+ t = -d1/(d3 - d1)
+ if (t > 0) and (t < 1):
+ y = y0*(1-t)*(1-t)*(1-t) + 3*y1*t*(1-t)*(1-t) + 3*y2*t*t*(1-t) + y3*t*t*t
+ cmin = min(cmin, y)
+ cmax = max(cmax, y)
+ return cmin, cmax
+
def computeBBox(aList,mat=[[1,0,0],[0,1,0]]):
bbox=None
for node in aList:
if d is not None:
p = cubicsuperpath.parsePath(d)
applyTransformToPath(m,p)
- bbox=boxunion(roughBBox(p),bbox)
+ bbox=boxunion(refinedBBox(p),bbox)
elif node.tag == inkex.addNS('use','svg') or node.tag=='use':
refid=node.get(inkex.addNS('href','xlink'))
return bbox
-# vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 encoding=utf-8 textwidth=99
+# vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 fileencoding=utf-8 textwidth=99