Are you a cartographer extraordinaire who’s encountered the frustrating phenomenon of maps in PDF format, generated by Python’s cartopy, refusing to concatenate in Adobe Illustrator? Fear not, dear map-maker, for we’re about to embark on a thrilling adventure to unravel the mystery behind this enigmatic error!
The Problem: Outlines outside the Artboard Scope
When attempting to concatenate multiple maps in Illustrator, you’re met with an error message that’s as cryptic as it is infuriating: “Outlines outside the artboard scope.” What does it mean? Why does it happen? And, more importantly, how do you fix it?
Understanding Cartopy’s PDF Generation
Cartopy, a Python library for creating geospatial visualizations, uses the Cairo graphics library to generate PDF files. When you create a map using cartopy, it produces a PDF with vector data, which is ideal for scaling and editing in Illustrator. However, this is where the trouble begins.
The issue lies in the way Cairo handles vector data. When creating a map, Cairo generates outlines that extend beyond the artboard scope, causing Illustrator to choke when trying to concatenate the maps. But fear not, we have a solution!
Solution 1: Trimming the Excess with Ghostscript
One way to tackle this problem is by using Ghostscript, a command-line tool for manipulating PDF files. This method involves trimming the excess vector data that’s causing the issue.
gs -o output.pdf -sDEVICE=pdfwrite -dCropBox -dTrimBox -d BleedBox -dArtifact input.pdfThis command uses Ghostscript to trim the excess vector data, effectively removing the outlines that extend beyond the artboard scope. The resulting PDF file should now be concatenatable in Illustrator.
Pros and Cons of the Ghostscript Method
| Pros | Cons |
|---|---|
| Easy to implement | May affect the map’s aesthetics |
| Fast processing time | Requires Ghostscript installation |
| Works for most cases | May not work for complex maps |
Solution 2: Editing the PDF with Inkscape
Another approach is to use Inkscape, a free and open-source vector graphics editor, to edit the PDF file and remove the excess vector data.
- Open the PDF file in Inkscape.
- Select the “Edit paths by nodes” tool (
F2). - Click on the map to select it.
- Go to
Path > Break Apartto break the path into individual segments. - Select the excess vector data (outside the artboard scope) and delete it.
- Save the edited PDF file.
This method provides more control over the editing process, allowing you to precision-edit the map and remove the problematic vector data.
Pros and Cons of the Inkscape Method
| Pros | Cons |
|---|---|
| More control over editing | Time-consuming process |
| Works for complex maps | Requires Inkscape installation |
| Preserves map aesthetics | Steep learning curve for Inkscape |
Solution 3: Tweaking Cartopy’s PDF Generation
Why not attack the problem at its source? By tweaking cartopy’s PDF generation, we can prevent the excess vector data from being created in the first place.
import cartopy.crs as ccrs
import cartopy.io.ogr as ogr
# Create a map with a custom bounding box
proj = ccrs. PlateCarree()
ax = plt.subplot(1, 1, 1, projection=proj)
ax.set_extent([-100, -90, 30, 40]) # Custom bounding box
# Generate the PDF with the bounding box
plt.savefig('output.pdf', bbox_inches='tight', dpi=300)By setting a custom bounding box using the `set_extent` method, we can restrict the vector data to within the artboard scope, eliminating the need for post-processing.
Pros and Cons of the Cartopy Tweaking Method
| Pros | Cons |
|---|---|
| Most elegant solution | Requires cartopy expertise |
| No post-processing needed | May not work for all map projections |
| Preserves map aesthetics | May require trial and error |
Conclusion: Taming the Unconcatenatable Maps
There you have it, folks! With these three solutions, you should be able to tame the unruly maps generated by cartopy and concatenate them with ease in Illustrator. Whether you choose to trim the excess with Ghostscript, edit the PDF with Inkscape, or tweak cartopy’s PDF generation, you’ll be well on your way to creating stunning, concatenatable maps.
Remember, the key to success lies in understanding the underlying causes of the problem and adapting your approach to your specific use case. So, go forth, conquer those maps, and may the artboard scope be ever in your favor!
Additional Resources
Happy mapping, and may your Illustrator concatenation woes be a thing of the past!
Frequently Asked Question
Get answers to the most pressing questions about concatenating PDF maps generated by Python Cartopy in Adobe Illustrator.
Why can’t I concatenate PDF maps generated by Python Cartopy in Adobe Illustrator?
This issue often arises due to outlines or paths extending beyond the artboard scope in the PDF files. Cartopy might be generating paths that exceed the paper size, causing Illustrator to throw a tantrum when trying to concatenate them. To troubleshoot, try adjusting the extent or bounds of your map to ensure all elements fit within the artboard.
How can I check if the outlines are indeed outside the artboard scope?
Easy one! Open the PDF file in a viewer like Acrobat or Preview, and zoom in on the map edges. If you notice any paths or lines jutting out beyond the artboard boundaries, that’s your culprit. Alternatively, you can use Illustrator’s built-in “Undo” feature to temporarily import the PDF and inspect the paths.
Can I modify the Cartopy code to prevent outlines from exceeding the artboard scope?
You can try tweaking the ` extent` or `bounds` parameters when creating your Cartopy map. For example, you can set the extent to match the desired paper size or artboard dimensions. This might require some trial and error, but it’s worth a shot! Consult the Cartopy documentation for more information on these parameters.
Are there any Illustrator-specific workarounds for concatenating these PDF maps?
Indeed! You can try using Illustrator’s “Place” feature instead of “Open” or “Import.” This might allow you to import the PDF files without the outlines causing issues. Another approach is to use the “Crop” tool to trim the PDF maps before concatenating them.
What if none of these solutions work? Are there any alternative tools or workflows?
Don’t worry, there are other options! Consider using other PDF editing software, like Inkscape or pdftk, to concatenate your maps. You can also explore alternative Python libraries, such as Matplotlib or Geoplotlib, to generate your maps. If all else fails, you might need to revisit your mapping workflow or seek guidance from a GIS expert.
