Hello,
I'd like to draw the map of a building using inkscape, and overlay my drawings with satellite views.
A batch program would then modify the map to adjust the position of some points.
Then I would like to import the svg file into sketchup and use it as a basis for quick 3d renderings.
And now the question: which units should I use for the canvas?
The building size is 50x15 meters. My first idea was to use this size as the canvas, but for some reason, in such a case, inkscape does not allow me to unzoom as much as I would like too (I cannot have the full drawing on screen).
Is there as reson for this and a workaround?
I know many maps and GIS use SVG somehow, how do they choose their basis unit? A Cheers
Hi,
I think you would be better off using a GIS than Inkscape for the compilation of your map. QGIS would be a good, GPL based, software for your task. In a GIS you can better define your units and projection and then export to DXF, which can be read in Sketchup.
The conversion of the GIS format (.e.g Shapefile, SpatiaLite, Postgis) to DXF may need manual conversion on the command line. OGR can help with that: http://www.gdal.org/ogr/drv_dxf.html - QGIS still needs some improvements for DXF import/Export.
regarding SVG and units: in QGIS you can use SVG for several purposes:
* point symbol definitions: You can use the SVG symbol and define its box in either map units or mm. The former scales with the zoom factor of the map, the latter stays at constant size, regardless of zoom factor. You can rotate and scale the symbols. * vector pattern definitions (uses the whole content of an SVG file, not a pattern definition) - you can repeat/scale/rotate the pattern * as a vector graphics in a map layout (print composer)
In all of these options, you don't define the objects in map units, but rather paper units. QGIS uses the SVG and scales it, starting from the viewBox/width/height settings.
Hope this helps, Andreas
On Fri, 4 Mar 2011 09:25:21 +0100, Sébastien Barthélémy wrote:
Hello,
I'd like to draw the map of a building using inkscape, and overlay my drawings with satellite views.
A batch program would then modify the map to adjust the position of some points.
Then I would like to import the svg file into sketchup and use it as a basis for quick 3d renderings.
And now the question: which units should I use for the canvas?
The building size is 50x15 meters. My first idea was to use this size as the canvas, but for some reason, in such a case, inkscape does not allow me to unzoom as much as I would like too (I cannot have the full drawing on screen).
Is there as reson for this and a workaround?
I know many maps and GIS use SVG somehow, how do they choose their basis unit? A Cheers
What You Don't Know About Data Connectivity CAN Hurt You This paper provides an overview of data connectivity, details its effect on application quality, and explores various alternative solutions. http://p.sf.net/sfu/progress-d2d _______________________________________________ Inkscape-user mailing list Inkscape-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/inkscape-user
On Fri, 04 Mar 2011 10:25:54 +0100 Andreas Neumann <a.neumann@...2251...> wrote:
I think you would be better off using a GIS than Inkscape for the compilation of your map. QGIS would be a good, GPL based, software for your task.
If you use QGIS, check out the OpenLayers plugin, which lets you put Google and Yahoo imagery in the background.
Cheers -Terry
Hi,
On Fri, 4 Mar 2011, Andreas Neumann wrote:
I think you would be better off using a GIS than Inkscape for the compilation of your map. QGIS would be a good, GPL based, software for your task.
Thank you for bringing qgis to my attention, but I'm not sure I'll use it for this project: I already know how to use inkscape and how to parse SVG, so I might simply go for SVG with a scale factor, as suggested by Terry (thank you Terry!).
Moreover I still haven't succeeded to install qgis with macports. I'm currently downloading the packages from www.kyngchaos.com, but it will be my last try to get it running.
regarding SVG and units: in QGIS you can use SVG for several purposes:
- point symbol definitions: You can use the SVG symbol and define its
box in either map units or mm. The former scales with the zoom factor of the map, the latter stays at constant size, regardless of zoom factor. You can rotate and scale the symbols.
- vector pattern definitions (uses the whole content of an SVG file,
not a pattern definition) - you can repeat/scale/rotate the pattern
- as a vector graphics in a map layout (print composer)
In all of these options, you don't define the objects in map units, but rather paper units. QGIS uses the SVG and scales it, starting from the viewBox/width/height settings.
Thank you for these explanations, this is the kind of data I was looking for.
Regards
On Fri, 4 Mar 2011 09:25:21 +0100 Sébastien Barthélémy <barthelemy@...1669...> wrote:
I know many maps and GIS use SVG somehow, how do they choose their basis unit?
I've just been doing some low level SVG map wrangling, but I just used a 1200px canvas and a scale factor. I knew the exact real world dimensions of the original image, so you could work out the meters per px for a given image size in px.
Cheers -Terry
On 03/04/2011 07:04 AM, Terry Brown wrote:
On Fri, 4 Mar 2011 09:25:21 +0100 Sébastien Barthélémy <barthelemy@...1669...> wrote:
I know many maps and GIS use SVG somehow, how do they choose their basis unit?
I've just been doing some low level SVG map wrangling, but I just used a 1200px canvas and a scale factor. I knew the exact real world dimensions of the original image, so you could work out the meters per px for a given image size in px.
Cheers -Terry
This might come in handy for that: http://www.unitconversion.org/unit_converter/typography.html http://www.unitconversion.org/unit_converter/typography-ex.html
participants (4)
-
Andreas Neumann -
NoOp -
Sébastien Barthélémy -
Terry Brown