[Inkscape-user] BUG in coordinate system (v0.44)

13 Jul 2006


      Hi,
I'm quite new to Inkscape but I the coordinate system handling is not 
getting clear to me, and I believe there must be a bug.
Basically I'm getting started by transformation of a shapefile to svg 
the important part is (one point to keep it simple):
<g
        inkscape:label="Ebene 1"
        inkscape:groupmode="layer"
        id="layer1">
       <g
          id="villages1">
         <circle
            r="0.01009"
            cy="-20.87945"
            cx="101.33645"
            id="villages1_B_Chaloen_Suk"
            sodipodi:cx="101.33645"
            sodipodi:cy="-20.87945"
            sodipodi:rx="0.01009"
            sodipodi:ry="0.01009" />
          </g>
         </g>
The -20.87945 is from conversion, the real coordinate is 20.87945 Degree 
north and 101.33645 degree east.
My full file is (more or less directly after import):
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!-- Created with Inkscape (http://www.inkscape.org/) -->
<svg
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:cc="http://web.resource.org/cc/"
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:svg="http://www.w3.org/2000/svg"
    xmlns="http://www.w3.org/2000/svg"
    xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
    xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
    width="100"
    height="100"
    id="svg2"
    sodipodi:version="0.32"
    inkscape:version="0.44"
    version="1.0"
    sodipodi:docbase="C:\Documents and Settings\s0167070\Desktop"
    sodipodi:docname="test.svg">
   <defs
      id="defs4" />
   <sodipodi:namedview
      id="base"
      pagecolor="#ffffff"
      bordercolor="#666666"
      borderopacity="1.0"
      inkscape:pageopacity="0.0"
      inkscape:pageshadow="2"
      inkscape:zoom="14.481547"
      inkscape:cx="10.67134"
      inkscape:cy="16.69171"
      inkscape:document-units="px"
      inkscape:current-layer="layer1"
      width="100"
      height="100"
      units="px"
      inkscape:window-width="1280"
      inkscape:window-height="751"
      inkscape:window-x="-4"
      inkscape:window-y="-4" />
   <metadata
      id="metadata7">
     rdf:RDF
       <cc:Work
          rdf:about="">
         dc:formatimage/svg+xml</dc:format>
         <dc:type
            rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
       </cc:Work>
     </rdf:RDF>
   </metadata>
     <g
        inkscape:label="Ebene 1"
        inkscape:groupmode="layer"
        id="layer1">
       <g
          id="villages1">
         <circle
            r="0.01009"
            cy="-20.87945"
            cx="101.33645"
            id="villages1_B_Chaloen_Suk"
            sodipodi:cx="101.33645"
            sodipodi:cy="-20.87945"
            sodipodi:rx="0.01009"
            sodipodi:ry="0.01009" />
          </g>
         </g>
</svg>
But the point is displayed at approx 101,120 so 100 px too high. 
Changing cy from -20.87945 to +20.... shifts the point to 101,79.1.. 
(reading from Inkscape properties). I assume the coordinate system 
starts above paper size?!
Next thing is that I want to shift the canvas origin from 0,0 to 0,100. 
Therefore I've added manually x="0 y="100" to the file:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!-- Created with Inkscape (http://www.inkscape.org/) -->
<svg
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:cc="http://web.resource.org/cc/"
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:svg="http://www.w3.org/2000/svg"
    xmlns="http://www.w3.org/2000/svg"
    xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
    xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
    x="0"
    y="100"
    width="100"
    height="100"
    id="svg2"
    sodipodi:version="0.32"
    inkscape:version="0.44"
    version="1.0"
    sodipodi:docbase="C:\Documents and Settings\s0167070\Desktop"
    sodipodi:docname="test.svg">
   <defs
      id="defs4" />
   <sodipodi:namedview
      id="base"
      pagecolor="#ffffff"
      bordercolor="#666666"
      borderopacity="1.0"
      inkscape:pageopacity="0.0"
      inkscape:pageshadow="2"
      inkscape:zoom="14.481547"
      inkscape:cx="10.67134"
      inkscape:cy="16.69171"
      inkscape:document-units="px"
      inkscape:current-layer="layer1"
      x="0"
      y="100"
      width="100"
      height="100"
      units="px"
      inkscape:window-width="1280"
      inkscape:window-height="751"
      inkscape:window-x="-4"
      inkscape:window-y="-4" />
   <metadata
      id="metadata7">
     rdf:RDF
       <cc:Work
          rdf:about="">
         dc:formatimage/svg+xml</dc:format>
         <dc:type
            rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
       </cc:Work>
     </rdf:RDF>
   </metadata>
     <g
        inkscape:label="Ebene 1"
        inkscape:groupmode="layer"
        id="layer1">
       <g
          id="villages1">
         <circle
            r="0.01009"
            cy="-20.87945"
            cx="101.33645"
            id="villages1_B_Chaloen_Suk"
            sodipodi:cx="101.33645"
            sodipodi:cy="-20.87945"
            sodipodi:rx="0.01009"
            sodipodi:ry="0.01009" />
          </g>
         </g>
</svg>
But this doesnt change anything at all!!! The point is still displayed 
at 101,120. And I assume the x,y statement is valid.
It gets even more strange if you put an additional <svg width="100" 
height="100"> ... </svg> statement around the last example:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!-- Created with Inkscape (http://www.inkscape.org/) -->
<svg
    width="100"
    height="100">
<svg
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:cc="http://web.resource.org/cc/"
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:svg="http://www.w3.org/2000/svg"
    xmlns="http://www.w3.org/2000/svg"
    xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
    xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
    x="0"
    y="100"
    width="100"
    height="100"
    id="svg2"
    sodipodi:version="0.32"
    inkscape:version="0.44"
    version="1.0"
    sodipodi:docbase="C:\Documents and Settings\s0167070\Desktop"
    sodipodi:docname="test.svg">
   <defs
      id="defs4" />
   <sodipodi:namedview
      id="base"
      pagecolor="#ffffff"
      bordercolor="#666666"
      borderopacity="1.0"
      inkscape:pageopacity="0.0"
      inkscape:pageshadow="2"
      inkscape:zoom="14.481547"
      inkscape:cx="10.67134"
      inkscape:cy="16.69171"
      inkscape:document-units="px"
      inkscape:current-layer="layer1"
      x="0"
      y="100"
      width="100"
      height="100"
      units="px"
      inkscape:window-width="1280"
      inkscape:window-height="751"
      inkscape:window-x="-4"
      inkscape:window-y="-4" />
   <metadata
      id="metadata7">
     rdf:RDF
       <cc:Work
          rdf:about="">
         dc:formatimage/svg+xml</dc:format>
         <dc:type
            rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
       </cc:Work>
     </rdf:RDF>
   </metadata>
     <g
        inkscape:label="Ebene 1"
        inkscape:groupmode="layer"
        id="layer1">
       <g
          id="villages1">
         <circle
            r="0.01009"
            cy="-20.87945"
            cx="101.33645"
            id="villages1_B_Chaloen_Suk"
            sodipodi:cx="101.33645"
            sodipodi:cy="-20.87945"
            sodipodi:rx="0.01009"
            sodipodi:ry="0.01009" />
          </g>
         </g>
</svg>
</svg>
Now the point is displayed at 101,-79.1 ! I dont understand why this 
should be correct! Especially as only the y coordinate is influenced. I 
really hope that somebody can explain me how I can move my image canvas 
so that it fits over my local coordinate system.
Thanks
Wolfgang