diff options
Diffstat (limited to 'imagemap.py')
| -rw-r--r-- | imagemap.py | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/imagemap.py b/imagemap.py new file mode 100644 index 0000000..4c4c931 --- /dev/null +++ b/imagemap.py @@ -0,0 +1,98 @@ +import inkex +from inkex import bezier +from inkex.command import inkscape_command + +# (X)HTML stuff: +ESCAPE=str.maketrans({'&':'&','<':'<','>':'>'}) +def quotedval(val): + quote="'" if val.count('"')>val.count("'") else '"' + return quote+val.translate(ESCAPE).translate({ord(quote):f'&#{ord(quote)}'})+quote +def htmlval(val): + if val=='': return '' + elif not any(i in val for i in ' \t\r\n\f"\'=`'): + return '='+val.translate(ESCAPE) + else: + return '='+quotedval(val) + +AREA_ATTRS={ + 'href':lambda a:a.get('href',a.get('{http://www.w3.org/1999/xlink}href')), + 'alt':lambda a:a.get('{http://www.w3.org/1999/xlink}title') +} # TODO target +SHAPE_MARKUP = { + 'HTML': lambda shape, coords, href, alt: + f"<area shape={shape} coords={','.join(str(c) for c in sum(coords,start=[]))}" + +(f' href{htmlval(href)}' if href is not None else '') + +(f' alt{htmlval(alt)}' if alt is not None else '')+">\n", + 'XHTML': lambda shape, coords, href, alt: + f"<area shape=\"{shape}\" coords=\"{','.join(str(c) for c in sum(coords,start=[]))}\"" + +(f" href={quotedval(href)}" if href is not None else '') + +(f' alt={quotedval(alt)}' if alt is not None else '')+"/>\n", + 'mod_imagemap': lambda shape, coords, href, alt: + f"{shape} {href if href is not None else 'nocontent'} {' '.join(f'{i[0]},{i[1]}' for i in coords)}" + +(f" \"{alt.translate({34:'"'})}\"" if alt is not None else '')+'\n' +} # if we ever implement `circ` we gotta handle it specially +CSS_LINK_INDEX='-computer-viatrix-inx-imagemap-linkindex' + +# "rectifiable" as in "can be made into a rect" +def rectifiable(coords): + if len(coords)!=4: return False + else: return (coords[0][0]==coords[1][0] and coords[1][1]==coords[2][1] and coords[2][0]==coords[3][0] and coords[3][1]==coords[0][1] ) \ + or (coords[0][1]==coords[1][1] and coords[1][0]==coords[2][0] and coords[2][1]==coords[3][1] and coords[0][0]==coords[3][0]) +def rectify(coords): + return [[min(coords[0][0],coords[2][0]),min(coords[0][1],coords[2][1])],[max(coords[0][0],coords[2][0]),max(coords[0][1],coords[2][1])]] + +class ImageMap(inkex.OutputExtension): + def add_arguments(self,pars): + pars.add_argument("--maptype") + def save(self,stream): + assert self.options.maptype in {"HTML","XHTML","mod_imagemap"} + shapemarkup=SHAPE_MARKUP[self.options.maptype] + + viewBox=self.svg.get_viewbox() + wscale=self.svg.viewport_width/viewBox[2] if viewBox[2]!=0 else 1 + hscale=self.svg.viewport_height/viewBox[3] if viewBox[3]!=0 else 1 + + # preprocess shapes for our purposes. + # after this, the shapes within the image must: look the same as before (barring colour/alpha), not be clones, have no stroke, not intersect, and be visually unaffected by `fill-rule`. + # TODO pay attention to clip-path + links=[] + for a in self.svg.iterdescendants('{http://www.w3.org/2000/svg}a'): + # save link attributes because they get removed when flattening + link={attr:AREA_ATTRS[attr](a) for attr in AREA_ATTRS.keys()} + for el in a.iterdescendants(): # CSS is preserved when flattening BUT NOT IN TEXT SO WE GOTTA FIGURE OUT HOW TODO TEXT + if not isinstance(el,inkex.ShapeElement): continue + style=el.effective_style() + style[CSS_LINK_INDEX]=f'" {CSS_LINK_INDEX}-{len(links)} "' + links += [link] + command='select-all;path-flatten;'+ \ + ';'.join(f'select-clear;select-by-selector:[style~="{CSS_LINK_INDEX}-{i}"];path-union;path-split' for i in range(len(links))) + newbytes=inkscape_command(self.svg,actions=command) + self.svg=self.load(newbytes).getroot() + + seen=set() + for el in self.svg.iterdescendants(): + if not isinstance(el,inkex.ShapeElement): continue + linkindex=el.cascaded_style().get(CSS_LINK_INDEX) + if linkindex is None: continue + linkindex=int(linkindex[len(CSS_LINK_INDEX)+3:-2]) + link=links[linkindex] + href=link['href'] + alt=link['alt'] if int(linkindex) not in seen else None + shapes=[] + path=el.get_path().to_superpath() + bezier.cspsubdiv(path,0.5) + for subpath in path: + coords=[[round((c[0][0]-viewBox[0])*wscale),round((c[0][1]-viewBox[1])*hscale)] for c in subpath] + i=0 + while i<len(coords): + if coords[i]==coords[(i+1)%len(coords)]: coords.pop(i) + else: i+=1 + if rectifiable(coords): shapes.append(shapemarkup('rect',rectify(coords),href,alt)) + elif len(coords)>=3: shapes.append(shapemarkup('poly',coords,href,alt)) + href=None # because subsequent subpaths must be enclaves + alt=None + seen.add(linkindex) + stream.write(bytes(''.join(reversed(shapes)),'utf-8')) + +if __name__ == "__main__": + ImageMap().run() |