#!/usr/bin/env python2 # openscad.py # This is an Inkscape extension to output paths to extruded OpenSCAD polygons # The Inkscape objects must first be converted to paths (Path > Object to Path). # Some paths may not work well -- the paths have to be polygons. As such, # paths derived from text may meet with mixed results. # Written by Daniel C. Newman ( dan dot newman at mtbaldy dot us ) # 10 June 2012 # 15 June 2012 # Updated by Dan Newman to handle a single level of polygon nesting. # This is sufficient to handle most fonts. # If you want to nest two polygons, combine them into a single path # within Inkscape with "Path > Combine Path". # 9 June 2017 # Modified by Eric Van Albert to output complex polygons instead of # using OpenSCAD's difference() # 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 import math import os.path import inkex import simplepath import simplestyle import simpletransform import cubicsuperpath import cspsubdiv import bezmisc import re DEFAULT_WIDTH = 100 DEFAULT_HEIGHT = 100 def parseLengthWithUnits( str ): ''' Parse an SVG value which may or may not have units attached This version is greatly simplified in that it only allows: no units, units of px, and units of %. Everything else, it returns None for. There is a more general routine to consider in scour.py if more generality is ever needed. ''' u = 'px' s = str.strip() if s[-2:] == 'px': s = s[:-2] elif s[-1:] == '%': u = '%' s = s[:-1] try: v = float( s ) except: return None, None return v, u def pointInBBox( pt, bbox ): ''' Determine if the point pt=[x, y] lies on or within the bounding box bbox=[xmin, xmax, ymin, ymax]. ''' # if ( x < xmin ) or ( x > xmax ) or ( y < ymin ) or ( y > ymax ) if ( pt[0] < bbox[0] ) or ( pt[0] > bbox[1] ) or \ ( pt[1] < bbox[2] ) or ( pt[1] > bbox[3] ): return False else: return True def bboxInBBox( bbox1, bbox2 ): ''' Determine if the bounding box bbox1 lies on or within the bounding box bbox2. NOTE: we do not test for strict enclosure. Structure of the bounding boxes is bbox1 = [ xmin1, xmax1, ymin1, ymax1 ] bbox2 = [ xmin2, xmax2, ymin2, ymax2 ] ''' # if ( xmin1 < xmin2 ) or ( xmax1 > xmax2 ) or ( ymin1 < ymin2 ) or ( ymax1 > ymax2 ) if ( bbox1[0] < bbox2[0] ) or ( bbox1[1] > bbox2[1] ) or \ ( bbox1[2] < bbox2[2] ) or ( bbox1[3] > bbox2[3] ): return False else: return True def pointInPoly( p, poly, bbox=None ): ''' Use a ray casting algorithm to see if the point p = [x, y] lies within the polygon poly = [[x1,y1],[x2,y2],...]. Returns True if the point is within poly, lies on an edge of poly, or is a vertex of poly. ''' if ( p is None ) or ( poly is None ): return False # Check to see if the point lies outside the polygon's bounding box if not bbox is None: if not pointInBBox( p, bbox ): return False # Check to see if the point is a vertex if p in poly: return True # Handle a boundary case associated with the point # lying on a horizontal edge of the polygon x = p[0] y = p[1] p1 = poly[0] p2 = poly[1] for i in range( len( poly ) ): if i != 0: p1 = poly[i-1] p2 = poly[i] if ( y == p1[1] ) and ( p1[1] == p2[1] ) and \ ( x > min( p1[0], p2[0] ) ) and ( x < max( p1[0], p2[0] ) ): return True n = len( poly ) inside = False p1_x,p1_y = poly[0] for i in range( n + 1 ): p2_x,p2_y = poly[i % n] if y > min( p1_y, p2_y ): if y <= max( p1_y, p2_y ): if x <= max( p1_x, p2_x ): if p1_y != p2_y: intersect = p1_x + (y - p1_y) * (p2_x - p1_x) / (p2_y - p1_y) if x <= intersect: inside = not inside else: inside = not inside p1_x,p1_y = p2_x,p2_y return inside def polyInPoly( poly1, bbox1, poly2, bbox2 ): ''' Determine if polygon poly2 = [[x1,y1],[x2,y2],...] contains polygon poly1. The bounding box information, bbox=[xmin, xmax, ymin, ymax] is optional. When supplied it can be used to perform rejections. Note that one bounding box containing another is not sufficient to imply that one polygon contains another. It's necessary, but not sufficient. ''' # See if poly1's bboundin box is NOT contained by poly2's bounding box # if it isn't, then poly1 cannot be contained by poly2. if ( not bbox1 is None ) and ( not bbox2 is None ): if not bboxInBBox( bbox1, bbox2 ): return False # To see if poly1 is contained by poly2, we need to ensure that each # vertex of poly1 lies on or within poly2 for p in poly1: if not pointInPoly( p, poly2, bbox2 ): return False # Looks like poly1 is contained on or in Poly2 return True def subdivideCubicPath( sp, flat, i=1 ): ''' [ Lifted from eggbot.py with impunity ] Break up a bezier curve into smaller curves, each of which is approximately a straight line within a given tolerance (the "smoothness" defined by [flat]). This is a modified version of cspsubdiv.cspsubdiv(): rewritten because recursion-depth errors on complicated line segments could occur with cspsubdiv.cspsubdiv(). ''' while True: while True: if i >= len( sp ): return p0 = sp[i - 1][1] p1 = sp[i - 1][2] p2 = sp[i][0] p3 = sp[i][1] b = ( p0, p1, p2, p3 ) if cspsubdiv.maxdist( b ) > flat: break i += 1 one, two = bezmisc.beziersplitatt( b, 0.5 ) sp[i - 1][2] = one[1] sp[i][0] = two[2] p = [one[2], one[3], two[1]] sp[i:1] = [p] class OpenSCAD( inkex.Effect ): def __init__( self ): inkex.Effect.__init__( self ) self.OptionParser.add_option( "--tab", #NOTE: value is not used. action="store", type="string", dest="tab", default="splash", help="The active tab when Apply was pressed" ) self.OptionParser.add_option('--smoothness', dest='smoothness', type='float', default=float( 0.02 ), action='store', help='Curve smoothing (less for more)' ) self.OptionParser.add_option('--fname', dest='fname', type='string', default='~/inkscape.scad', action='store', help='Curve smoothing (less for more)' ) self.cx = float( DEFAULT_WIDTH ) / 2.0 self.cy = float( DEFAULT_HEIGHT ) / 2.0 self.xmin, self.xmax = ( 1.0E70, -1.0E70 ) self.ymin, self.ymax = ( 1.0E70, -1.0E70 ) # Dictionary of paths we will construct. It's keyed by the SVG node # it came from. Such keying isn't too useful in this specific case, # but it can be useful in other applications when you actually want # to go back and update the SVG document self.paths = {} # Output file handling self.call_list = [] self.pathid = int( 0 ) # Output file self.f = None # For handling an SVG viewbox attribute, we will need to know the # values of the document's width and height attributes as well # as establishing a transform from the viewbox to the display. self.docWidth = float( DEFAULT_WIDTH ) self.docHeight = float( DEFAULT_HEIGHT ) self.docTransform = [[1.0, 0.0, 0.0], [0.0, 1.0, 0.0]] # Dictionary of warnings issued. This to prevent from warning # multiple times about the same problem self.warnings = {} def getLength( self, name, default ): ''' Get the attribute with name "name" and default value "default" Parse the attribute into a value and associated units. Then, accept units of cm, ft, in, m, mm, pc, or pt. Convert to pixels. Note that SVG defines 90 px = 1 in = 25.4 mm. ''' str = self.document.getroot().get( name ) if str: v, u = parseLengthWithUnits( str ) if not v: # Couldn't parse the value return None elif ( u == 'mm' ): return float( v ) * ( 90.0 / 25.4 ) elif ( u == 'cm' ): return float( v ) * ( 90.0 * 10.0 / 25.4 ) elif ( u == 'm' ): return float( v ) * ( 90.0 * 1000.0 / 25.4 ) elif ( u == 'in' ): return float( v ) * 90.0 elif ( u == 'ft' ): return float( v ) * 12.0 * 90.0 elif ( u == 'pt' ): # Use modern "Postscript" points of 72 pt = 1 in instead # of the traditional 72.27 pt = 1 in return float( v ) * ( 90.0 / 72.0 ) elif ( u == 'pc' ): return float( v ) * ( 90.0 / 6.0 ) elif ( u == 'px' ): return float( v ) else: # Unsupported units return None else: # No width specified; assume the default value return float( default ) def getDocProps( self ): ''' Get the document's height and width attributes from the tag. Use a default value in case the property is not present or is expressed in units of percentages. ''' self.docHeight = self.getLength( 'height', DEFAULT_HEIGHT ) self.docWidth = self.getLength( 'width', DEFAULT_WIDTH ) if ( self.docHeight == None ) or ( self.docWidth == None ): return False else: return True def handleViewBox( self ): ''' Set up the document-wide transform in the event that the document has an SVG viewbox ''' if self.getDocProps(): viewbox = self.document.getroot().get( 'viewBox' ) if viewbox: vinfo = viewbox.strip().replace( ',', ' ' ).split( ' ' ) if ( vinfo[2] != 0 ) and ( vinfo[3] != 0 ): sx = self.docWidth / float( vinfo[2] ) sy = self.docHeight / float( vinfo[3] ) self.docTransform = simpletransform.parseTransform( 'scale(%f,%f)' % (sx, sy) ) def getPathVertices( self, path, node=None, transform=None ): ''' Decompose the path data from an SVG element into individual subpaths, each subpath consisting of absolute move to and line to coordinates. Place these coordinates into a list of polygon vertices. ''' if ( not path ) or ( len( path ) == 0 ): # Nothing to do return None # parsePath() may raise an exception. This is okay sp = simplepath.parsePath( path ) if ( not sp ) or ( len( sp ) == 0 ): # Path must have been devoid of any real content return None # Get a cubic super path p = cubicsuperpath.CubicSuperPath( sp ) if ( not p ) or ( len( p ) == 0 ): # Probably never happens, but... return None if transform: simpletransform.applyTransformToPath( transform, p ) # Now traverse the cubic super path subpath_list = [] subpath_vertices = [] for sp in p: # We've started a new subpath # See if there is a prior subpath and whether we should keep it if len( subpath_vertices ): subpath_list.append( [ subpath_vertices, [ sp_xmin, sp_xmax, sp_ymin, sp_ymax ] ] ) subpath_vertices = [] subdivideCubicPath( sp, float( self.options.smoothness ) ) # Note the first point of the subpath first_point = sp[0][1] subpath_vertices.append( first_point ) sp_xmin = first_point[0] sp_xmax = first_point[0] sp_ymin = first_point[1] sp_ymax = first_point[1] # See if the first and last points are identical # OpenSCAD doesn't mind if we duplicate the first and last # vertex, but our polygon in polygon algorithm may n = len( sp ) last_point = sp[n-1][1] if ( first_point[0] == last_point[0] ) and ( first_point[1] == last_point[1] ): n = n - 1 # Traverse each point of the subpath for csp in sp[1:n]: # Append the vertex to our list of vertices pt = csp[1] subpath_vertices.append( pt ) # Track the bounding box of this subpath if pt[0] < sp_xmin: sp_xmin = pt[0] elif pt[0] > sp_xmax: sp_xmax = pt[0] if pt[1] < sp_ymin: sp_ymin = pt[1] elif pt[1] > sp_ymax: sp_ymax = pt[1] # Track the bounding box of the overall drawing # This is used for centering the polygons in OpenSCAD around the (x,y) origin if sp_xmin < self.xmin: self.xmin = sp_xmin if sp_xmax > self.xmax: self.xmax = sp_xmax if sp_ymin < self.ymin: self.ymin = sp_ymin if sp_ymax > self.ymax: self.ymax = sp_ymax # Handle the final subpath if len( subpath_vertices ): subpath_list.append( [ subpath_vertices, [ sp_xmin, sp_xmax, sp_ymin, sp_ymax ] ] ) if len( subpath_list ) > 0: self.paths[node] = subpath_list def convertPath( self, node ): path = self.paths[node] if ( path is None ) or ( len( path ) == 0 ): return # Determine which polys contain which contains = [ [] for i in xrange( len( path ) ) ] contained_by = [ [] for i in xrange( len( path ) ) ] for i in range( 0, len( path ) ): for j in range( i + 1, len( path ) ): if polyInPoly( path[j][0], path[j][1], path[i][0], path[i][1] ): # subpath i contains subpath j contains[i].append( j ) # subpath j is contained in subpath i contained_by[j].append( i ) elif polyInPoly( path[i][0], path[i][1], path[j][0], path[j][1] ): # subpath j contains subpath i contains[j].append( i ) # subpath i is containd in subpath j contained_by[i].append( j ) # Generate an OpenSCAD module for this path id = node.get ( 'id', '' ) if ( id is None ) or ( id == '' ): id = str( self.pathid ) + 'x' self.pathid += 1 else: id = re.sub( '[^A-Za-z0-9_]+', '', id ) scale = (1, -1) # We appear to be working in mm by this point # And add the call to the call list self.call_list.append( '//polygon(points={0}_points, paths={0}_paths);\n'.format(id) ) points = [] paths = [] for i in range( 0, len( path ) ): # Skip this subpath if it is contained by another one if len( contained_by[i] ) != 0: continue subpath = path[i][0] bbox = path[i][1] one_path = [] for point in subpath: one_path.append(len(points)) points.append((point[0] - self.cx, point[1] - self.cy )) paths.append(one_path) if len( contains[i] ) != 0: for j in contains[i]: one_path = [] for point in path[j][0]: one_path.append(len(points)) points.append((point[0] - self.cx, point[1] - self.cy )) paths.append(list(reversed(one_path))) points_str = "[{}]".format(", ".join(["[{:8f}, {:8f}]".format(x * scale[0], y * scale[1]) for (x, y) in points])) paths_str = "[{}]".format(", ".join(["[{}]".format(", ".join(["{:d}".format(i) for i in indices])) for indices in paths])) self.f.write( '{}_points = {};\n'.format(id, points_str) ) self.f.write( '{}_paths = {};\n'.format(id, paths_str) ) def recursivelyTraverseSvg( self, aNodeList, matCurrent=[[1.0, 0.0, 0.0], [0.0, 1.0, 0.0]], parent_visibility='visible' ): ''' [ This too is largely lifted from eggbot.py ] Recursively walk the SVG document, building polygon vertex lists for each graphical element we support. Rendered SVG elements: , , , , , , Supported SVG elements: , Ignored SVG elements: , , , , , processing directives All other SVG elements trigger an error (including ) ''' for node in aNodeList: # Ignore invisible nodes v = node.get( 'visibility', parent_visibility ) if v == 'inherit': v = parent_visibility if v == 'hidden' or v == 'collapse': pass # First apply the current matrix transform to this node's tranform matNew = simpletransform.composeTransform( matCurrent, simpletransform.parseTransform( node.get( "transform" ) ) ) if node.tag == inkex.addNS( 'g', 'svg' ) or node.tag == 'g': self.recursivelyTraverseSvg( node, matNew, v ) elif node.tag == inkex.addNS( 'use', 'svg' ) or node.tag == 'use': # A element refers to another SVG element via an xlink:href="#blah" # attribute. We will handle the element by doing an XPath search through # the document, looking for the element with the matching id="blah" # attribute. We then recursively process that element after applying # any necessary (x,y) translation. # # Notes: # 1. We ignore the height and width attributes as they do not apply to # path-like elements, and # 2. Even if the use element has visibility="hidden", SVG still calls # for processing the referenced element. The referenced element is # hidden only if its visibility is "inherit" or "hidden". refid = node.get( inkex.addNS( 'href', 'xlink' ) ) if not refid: pass # [1:] to ignore leading '#' in reference path = '//*[@id="%s"]' % refid[1:] refnode = node.xpath( path ) if refnode: x = float( node.get( 'x', '0' ) ) y = float( node.get( 'y', '0' ) ) # Note: the transform has already been applied if ( x != 0 ) or (y != 0 ): matNew2 = composeTransform( matNew, parseTransform( 'translate(%f,%f)' % (x,y) ) ) else: matNew2 = matNew v = node.get( 'visibility', v ) self.recursivelyTraverseSvg( refnode, matNew2, v ) elif node.tag == inkex.addNS( 'path', 'svg' ): path_data = node.get( 'd') if path_data: self.getPathVertices( path_data, node, matNew ) elif node.tag == inkex.addNS( 'rect', 'svg' ) or node.tag == 'rect': # Manually transform # # # # into # # # # I.e., explicitly draw three sides of the rectangle and the # fourth side implicitly # Create a path with the outline of the rectangle x = float( node.get( 'x' ) ) y = float( node.get( 'y' ) ) if ( not x ) or ( not y ): pass w = float( node.get( 'width', '0' ) ) h = float( node.get( 'height', '0' ) ) a = [] a.append( ['M ', [x, y]] ) a.append( [' l ', [w, 0]] ) a.append( [' l ', [0, h]] ) a.append( [' l ', [-w, 0]] ) a.append( [' Z', []] ) self.getPathVertices( simplepath.formatPath( a ), node, matNew ) elif node.tag == inkex.addNS( 'line', 'svg' ) or node.tag == 'line': # Convert # # x1 = float( node.get( 'x1' ) ) y1 = float( node.get( 'y1' ) ) x2 = float( node.get( 'x2' ) ) y2 = float( node.get( 'y2' ) ) if ( not x1 ) or ( not y1 ) or ( not x2 ) or ( not y2 ): pass a = [] a.append( ['M ', [x1, y1]] ) a.append( [' L ', [x2, y2]] ) self.getPathVertices( simplepath.formatPath( a ), node, matNew ) elif node.tag == inkex.addNS( 'polyline', 'svg' ) or node.tag == 'polyline': # Convert # # # # to # # # # Note: we ignore polylines with no points pl = node.get( 'points', '' ).strip() if pl == '': pass pa = pl.split() d = "".join( ["M " + pa[i] if i == 0 else " L " + pa[i] for i in range( 0, len( pa ) )] ) self.getPathVertices( d, node, matNew ) elif node.tag == inkex.addNS( 'polygon', 'svg' ) or node.tag == 'polygon': # Convert # # # # to # # # # Note: we ignore polygons with no points pl = node.get( 'points', '' ).strip() if pl == '': pass pa = pl.split() d = "".join( ["M " + pa[i] if i == 0 else " L " + pa[i] for i in range( 0, len( pa ) )] ) d += " Z" self.getPathVertices( d, node, matNew ) elif node.tag == inkex.addNS( 'ellipse', 'svg' ) or \ node.tag == 'ellipse' or \ node.tag == inkex.addNS( 'circle', 'svg' ) or \ node.tag == 'circle': # Convert circles and ellipses to a path with two 180 degree arcs. # In general (an ellipse), we convert # # # # to # # # # where # # X1 = CX - RX # X2 = CX + RX # # Note: ellipses or circles with a radius attribute of value 0 are ignored if node.tag == inkex.addNS( 'ellipse', 'svg' ) or node.tag == 'ellipse': rx = float( node.get( 'rx', '0' ) ) ry = float( node.get( 'ry', '0' ) ) else: rx = float( node.get( 'r', '0' ) ) ry = rx if rx == 0 or ry == 0: pass cx = float( node.get( 'cx', '0' ) ) cy = float( node.get( 'cy', '0' ) ) x1 = cx - rx x2 = cx + rx d = 'M %f,%f ' % ( x1, cy ) + \ 'A %f,%f ' % ( rx, ry ) + \ '0 1 0 %f,%f ' % ( x2, cy ) + \ 'A %f,%f ' % ( rx, ry ) + \ '0 1 0 %f,%f' % ( x1, cy ) self.mapPathVertices( d, node, matNew ) elif node.tag == inkex.addNS( 'pattern', 'svg' ) or node.tag == 'pattern': pass elif node.tag == inkex.addNS( 'metadata', 'svg' ) or node.tag == 'metadata': pass elif node.tag == inkex.addNS( 'defs', 'svg' ) or node.tag == 'defs': pass elif node.tag == inkex.addNS( 'desc', 'svg' ) or node.tag == 'desc': pass elif node.tag == inkex.addNS( 'namedview', 'sodipodi' ) or node.tag == 'namedview': pass elif node.tag == inkex.addNS( 'eggbot', 'svg' ) or node.tag == 'eggbot': pass elif node.tag == inkex.addNS( 'text', 'svg' ) or node.tag == 'text': inkex.errormsg( 'Warning: unable to draw text, please convert it to a path first.' ) pass elif node.tag == inkex.addNS( 'title', 'svg' ) or node.tag == 'title': pass elif node.tag == inkex.addNS( 'image', 'svg' ) or node.tag == 'image': if not self.warnings.has_key( 'image' ): inkex.errormsg( 'Warning: unable to draw bitmap images; ' + 'please convert them to line art first. Consider using the "Trace bitmap..." ' + 'tool of the "Path" menu. Mac users please note that some X11 settings may ' + 'cause cut-and-paste operations to paste in bitmap copies.' ) self.warnings['image'] = 1 pass elif node.tag == inkex.addNS( 'pattern', 'svg' ) or node.tag == 'pattern': pass elif node.tag == inkex.addNS( 'radialGradient', 'svg' ) or node.tag == 'radialGradient': # Similar to pattern pass elif node.tag == inkex.addNS( 'linearGradient', 'svg' ) or node.tag == 'linearGradient': # Similar in pattern pass elif node.tag == inkex.addNS( 'style', 'svg' ) or node.tag == 'style': # This is a reference to an external style sheet and not the value # of a style attribute to be inherited by child elements pass elif node.tag == inkex.addNS( 'cursor', 'svg' ) or node.tag == 'cursor': pass elif node.tag == inkex.addNS( 'color-profile', 'svg' ) or node.tag == 'color-profile': # Gamma curves, color temp, etc. are not relevant to single color output pass elif not isinstance( node.tag, basestring ): # This is likely an XML processing instruction such as an XML # comment. lxml uses a function reference for such node tags # and as such the node tag is likely not a printable string. # Further, converting it to a printable string likely won't # be very useful. pass else: inkex.errormsg( 'Warning: unable to draw object <%s>, please convert it to a path first.' % node.tag ) pass def recursivelyGetEnclosingTransform( self, node ): ''' Determine the cumulative transform which node inherits from its chain of ancestors. ''' node = node.getparent() if node is not None: parent_transform = self.recursivelyGetEnclosingTransform( node ) node_transform = node.get( 'transform', None ) if node_transform is None: return parent_transform else: tr = simpletransform.parseTransform( node_transform ) if parent_transform is None: return tr else: return simpletransform.composeTransform( parent_transform, tr ) else: return self.docTransform def effect( self ): # Viewbox handling self.handleViewBox() # First traverse the document (or selected items), reducing # everything to line segments. If working on a selection, # then determine the selection's bounding box in the process. # (Actually, we just need to know it's extrema on the x-axis.) if self.options.ids: # Traverse the selected objects for id in self.options.ids: transform = self.recursivelyGetEnclosingTransform( self.selected[id] ) self.recursivelyTraverseSvg( [self.selected[id]], transform ) else: # Traverse the entire document building new, transformed paths self.recursivelyTraverseSvg( self.document.getroot(), self.docTransform ) # Determine the center of the drawing's bounding box self.cx = self.xmin + ( self.xmax - self.xmin ) / 2.0 self.cy = self.ymin + ( self.ymax - self.ymin ) / 2.0 # Determine which polygons lie entirely within other polygons try: if '/' == os.sep: self.f = open( os.path.expanduser( self.options.fname ), 'w') else: self.f = open( os.path.expanduser( self.options.fname ).replace('/', os.sep), 'w') self.f.write('''// Automatically generated using the Inkscape to OpenSCAD Converter // Variable names are of the form _points and // _paths. As a result, you can associate a polygon in this // OpenSCAD program with the corresponding SVG element in the Inkscape document // by looking for the XML element with the attribute id=\"inkscape-path-id\". ''' ) for key in self.paths: self.f.write( '\n' ) self.convertPath( key ) # Now output the list of modules to call self.f.write( '\n' ) for call in self.call_list: self.f.write( call ) except IOError: inkex.errormsg( 'Unable to open the file ' + self.options.fname ) if __name__ == '__main__': e = OpenSCAD() e.affect()