simpletransform.py revision ed9a4e997299e470937019319f71f2467e9e2b86
#!/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
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
barraud@math.univ-lille1.fr
This code defines several functions to make handling of transform
attribute easier.
'''
import inkex, cubicsuperpath, bezmisc, simplestyle
import copy, math, re
def parseTransform(transf,mat=[[1.0, 0.0, 0.0], [0.0, 1.0, 0.0]]):
if transf=="" or transf==None:
return(mat)
stransf = transf.strip()
result=re.match("(translate|scale|rotate|skewX|skewY|matrix)\s*\(([^)]*)\)\s*,?",stransf)
#-- translate --
if result.group(1)=="translate":
args=result.group(2).replace(',',' ').split()
dx=float(args[0])
if len(args)==1:
dy=0.0
else:
dy=float(args[1])
matrix=[[1,0,dx],[0,1,dy]]
#-- scale --
if result.group(1)=="scale":
args=result.group(2).replace(',',' ').split()
sx=float(args[0])
if len(args)==1:
sy=sx
else:
sy=float(args[1])
matrix=[[sx,0,0],[0,sy,0]]
#-- rotate --
if result.group(1)=="rotate":
args=result.group(2).replace(',',' ').split()
a=float(args[0])*math.pi/180
if len(args)==1:
cx,cy=(0.0,0.0)
else:
cx,cy=map(float,args[1:])
matrix=[[math.cos(a),-math.sin(a),cx],[math.sin(a),math.cos(a),cy]]
matrix=composeTransform(matrix,[[1,0,-cx],[0,1,-cy]])
#-- skewX --
if result.group(1)=="skewX":
a=float(result.group(2))*math.pi/180
matrix=[[1,math.tan(a),0],[0,1,0]]
#-- skewY --
if result.group(1)=="skewY":
a=float(result.group(2))*math.pi/180
matrix=[[1,0,0],[math.tan(a),1,0]]
#-- matrix --
if result.group(1)=="matrix":
a11,a21,a12,a22,v1,v2=result.group(2).replace(',',' ').split()
matrix=[[float(a11),float(a12),float(v1)], [float(a21),float(a22),float(v2)]]
matrix=composeTransform(mat,matrix)
if result.end() < len(stransf):
return(parseTransform(stransf[result.end():], matrix))
else:
return matrix
def formatTransform(mat):
return ("matrix(%f,%f,%f,%f,%f,%f)" % (mat[0][0], mat[1][0], mat[0][1], mat[1][1], mat[0][2], mat[1][2]))
def composeTransform(M1,M2):
a11 = M1[0][0]*M2[0][0] + M1[0][1]*M2[1][0]
a12 = M1[0][0]*M2[0][1] + M1[0][1]*M2[1][1]
a21 = M1[1][0]*M2[0][0] + M1[1][1]*M2[1][0]
a22 = M1[1][0]*M2[0][1] + M1[1][1]*M2[1][1]
v1 = M1[0][0]*M2[0][2] + M1[0][1]*M2[1][2] + M1[0][2]
v2 = M1[1][0]*M2[0][2] + M1[1][1]*M2[1][2] + M1[1][2]
return [[a11,a12,v1],[a21,a22,v2]]
def composeParents(node, mat):
trans = node.get('transform')
if trans:
mat = composeTransform(parseTransform(trans), mat)
if node.getparent().tag == inkex.addNS('g','svg'):
mat = composeParents(node.getparent(), mat)
return mat
def applyTransformToNode(mat,node):
m=parseTransform(node.get("transform"))
newtransf=formatTransform(composeTransform(mat,m))
node.set("transform", newtransf)
def applyTransformToPoint(mat,pt):
x = mat[0][0]*pt[0] + mat[0][1]*pt[1] + mat[0][2]
y = mat[1][0]*pt[0] + mat[1][1]*pt[1] + mat[1][2]
pt[0]=x
pt[1]=y
def applyTransformToPath(mat,path):
for comp in path:
for ctl in comp:
for pt in ctl:
applyTransformToPoint(mat,pt)
def fuseTransform(node):
if node.get('d')==None:
#FIXME: how do you raise errors?
raise AssertionError, 'can not fuse "transform" of elements that have no "d" attribute'
t = node.get("transform")
if t == None:
return
m = parseTransform(t)
d = node.get('d')
p = cubicsuperpath.parsePath(d)
applyTransformToPath(m,p)
node.set('d', cubicsuperpath.formatPath(p))
del node.attrib["transform"]
####################################################################
##-- Some functions to compute a rough bbox of a given list of objects.
##-- this should be shipped out in an separate file...
def boxunion(b1,b2):
if b1 is None:
return b2
elif b2 is None:
return b1
else:
return((min(b1[0],b2[0]), max(b1[1],b2[1]), min(b1[2],b2[2]), max(b1[3],b2[3])))
def roughBBox(path):
xmin,xMax,ymin,yMax = path[0][0][0][0],path[0][0][0][0],path[0][0][0][1],path[0][0][0][1]
for pathcomp in path:
for ctl in pathcomp:
for pt in ctl:
xmin = min(xmin,pt[0])
xMax = max(xMax,pt[0])
ymin = min(ymin,pt[1])
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:
m = parseTransform(node.get('transform'))
m = composeTransform(mat,m)
#TODO: text not supported!
d = None
if node.get("d"):
d = node.get('d')
elif node.get('points'):
d = 'M' + node.get('points')
elif node.tag in [ inkex.addNS('rect','svg'), 'rect', inkex.addNS('image','svg'), 'image' ]:
d = 'M' + node.get('x', '0') + ',' + node.get('y', '0') + \
'h' + node.get('width') + 'v' + node.get('height') + \
'h-' + node.get('width')
elif node.tag in [ inkex.addNS('line','svg'), 'line' ]:
d = 'M' + node.get('x1') + ',' + node.get('y1') + \
' ' + node.get('x2') + ',' + node.get('y2')
elif node.tag in [ inkex.addNS('circle','svg'), 'circle', \
inkex.addNS('ellipse','svg'), 'ellipse' ]:
rx = node.get('r')
if rx is not None:
ry = rx
else:
rx = node.get('rx')
ry = node.get('ry')
cx = float(node.get('cx', '0'))
cy = float(node.get('cy', '0'))
x1 = cx - float(rx)
x2 = cx + float(rx)
d = 'M %f %f ' % (x1, cy) + \
'A' + rx + ',' + ry + ' 0 1 0 %f,%f' % (x2, cy) + \
'A' + rx + ',' + ry + ' 0 1 0 %f,%f' % (x1, cy)
if d is not None:
p = cubicsuperpath.parsePath(d)
applyTransformToPath(m,p)
bbox=boxunion(refinedBBox(p),bbox)
elif node.tag == inkex.addNS('use','svg') or node.tag=='use':
refid=node.get(inkex.addNS('href','xlink'))
path = '//*[@id="%s"]' % refid[1:]
refnode = node.xpath(path)
bbox=boxunion(computeBBox(refnode,m),bbox)
bbox=boxunion(computeBBox(node,m),bbox)
return bbox
# vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 fileencoding=utf-8 textwidth=99