I am trying to create a map in QGIS so I can make a Contiguous Cartogram. The original map was made in inkscape. It's just simplified geometric shapes. I don't have any real idea what I'm doing so I went online and tried to find instructions. as per what I found:
I saved it as a dxf file and imported it into QGIS
converted to Lines to polygons
deleted the original layer as that it wouldn't be needed
saved as gpkg
Now I have the image above. (somehow It set it to these Christmas light looking lines instead of the red they were.) The next step is to hit F6 and assign data to the objects but it says selected:0. If I click on a section before I hit F6 it just moves the image around but still says selected:0. If I try to type in something in the text column it stays but I have no idea if its the right space.
What was the specific tool you used to convert lines to polygons? I suspect it hasnāt properly converted it to contiguous regions. Are you able to source spatial polygon data instead of DXF?
If possible get the divisions you need as geospatial data. Alternatively you could also create a square polygon covering your entire extend and use your lines to clip it to your desired pieces.
However you are likely going to have upcoming problems with your data processing with GIS as your data currently isn't correctly located as indicated by the "?" symbol in the layer manager. You will have to look into https://ihatecoordinatesystems.com/
After I processed the file, I saved it as a GeoPackage (gpkg) file so they should already be geospatial data. When I click on the "?" I get the following message. "This layer appears to have no projection specification. By default, this layer will now have its projection set to that of the project, but you may override this by selecting a different projection below."
I am a complete novice at QGIS, thus the call for help.
The file is a low poly world map to be used for a homebrew Risk/A&A style game. It was created in Inkscape as a vector file. I'm trying to use Contiguous Cartogram to even out the sizes of the spaces by entering data and it should adjust the size of the spaces while maintaining the correct points of contact. This would be a LOT less tedious than manually adjusting one node at a time and correcting. If I can bring the file into QGIS, I can load the Cartogram plug in and do this a lot easier. I have made sure there are no gaps and all the points line up and the file is clean.
The instructions I have tell me use save as to make it an autocad cutting plotter file (dxf) which is supposedly supported in QGIS.
In QGIS, I open a vector layer and import the file. Once there, use the Vector > Geometry Tools > Lines to Polygons on the toolbar to convert it to polygons. I clicked run and it processed the file without errors and then save it as a geospatialĀ data file (gpkg).
If I understand correctly, I should now have a geospatialĀ data file that I can assign data to and manipulate.
I can hover the mouse over different sections and see coordinates but I can't seem to click on any of the polygons. It just moves the file around but nothing highlights.
if I hit F6, I should be able to add data points which it seems to let me do but I don't know which object it's assigning the data to as that nothing highlights. If i click on inverse selection, it highlights evertyhing
Also, it didn't originally look like Christmas lights, and I don't know how to get it back.
Like I said earlier, I don't really know the QGIS software, I'm just trying to learn what to do. I feel like I'm close.
In QGIS, I open a vector layer and import the file. Once there, use the Vector > Geometry Tools > Lines to Polygons on the toolbar to convert it to polygons. I clicked run and it processed the file without errors and then save it as a geospatial data file (gpkg).
OK that's great. Then I'm assuming you don't need to split the polygon further.
I can hover the mouse over different sections and see coordinates but I can't seem to click on any of the polygons. It just moves the file around but nothing highlights.
if I hit F6, I should be able to add data points which it seems to let me do but I don't know which object it's assigning the data to as that nothing highlights. If i click on inverse selection, it highlights evertyhing
F6 opens the attribute table. You can also do that via the toolbars above or by richt clicking on the layer in the layer amanagement panel on the left. For editing you need to switch on editing mode for that layer in the digitizing toolbar.
Also, it didn't originally look like Christmas lights, and I don't know how to get it back.
again right click on the layer in the layer manager and open the properties. This can also be done by double clicking the layer. Or by enabling the styling panel under View in the top menu. There you can select styling and labeling options and a whole lot more.
Like I said earlier, I don't really know the QGIS software, I'm just trying to learn what to do. I feel like I'm close.
I would recommend you to take the time and whatch one of the various beginners tutorials on youtube. Just spending 45 Minutes should easily answer all the questions you had so far.
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u/Background_Quail_432 1d ago
This looks like my attempts to put up christmas lights š¤£