Help:Making detailed forest cover
This page is intended to show advanced OGF users how to make detailed forest cover polygons using isleño's technique for Gobrassanya, Suvuma and West Commonia.
 Warning: this can be difficult, time consuming, and sloppy.
It also requires a working knowledge of Inkscape vector graphics software and the JOSM map editor. It's not easy, it can take a huge amount of effort, and it can cause massive headaches. In addition, some people would say it's bad form in OGF to use textures from the real world... and on top of that, some people don't like the look of the end product. So, attempt only at your own risk. |
1. Take a screenshot of the OGF area you'll be working with, and import into Inkscape
Use it to make a general plan for where you want the forest cover.
2. Find the perfect texture and use the Trace Bitmap function to create a vector shape
Next, spend some time doing image searches to find a detailed map of forest/vegetation cover. Finding a good image can be really hard. You need a map that features really interesting textures, and shows them at reasonably high resolution, and with reasonably high light/dark contrast. On top of that, you should make sure that the map is public domain (most images produced by NASA, the US Forest Service, or other US government agencies are). For this example we're getting our texture from a public domain NASA map of deforestation in Paraguay.
Once you decide on an image, paste it into Inkscape and use "Trace Bitmap" function to create a vector shape of the image's dark areas. Then delete the image, leaving only the vector shape.
3. Cut the shape into lots of small pieces
Ideally you'll want to cut in such a way that breaks the fragments into usable groups, and minimizes the length of straight cut lines.
4. Reassemble the small pieces to form a completely new shape
This can be insanely hard. The challenge is to take the pieces and reassemble them using the screenshot as a background and your sketch as a guide. Not only that, but the new shape needs to look natural and fit with the local geography. And the pieces need to be arranged so that the straight edges where you cut are hidden by other pieces.
This step is like a crazy puzzle. It can be really hard and take a lot of time. Please do not attempt this unless you actually think you'd enjoy it. You may need to do lots of rotating pieces, flipping pieces, cutting larger pieces into smaller ones, adjusting and readjusting, overlapping them in different ways. You may even decide to import another image and repeat the previous step to acquire more pieces, or even draw a few custom pieces of your own, if you can match the level of detail.
5. Combine the pieces and export as .svg file
When everything is perfect, use Inkscape's "Path → Union" tool to combine all the pieces into a single object. Save the object by itself as an .svg file.
6. Import to JOSM, create multipolygon, reposition, resize and cleanup
Install the ImportVec plugin for JOSM and use it to import the .svg file. You'll need to resize it and reposition it in the right place... and this can be a nightmare with many thousands of objects, especially if you're working on a slow machine or if you lack the most amazing JOSM skills. Using the "Create multipolygon" tool can also be annoying, especially if there are any errors in your multipolygon (crossing paths, etc). It can also take forever to upload everything to OGF, to clean up afterwards and tweak things so they look just right, etc, etc.
So... seriously, if you have any sense, turn back now, haha.
Finally
If you have questions, feel free to ask on the talk page here, or contact isleño... but don't expect isleño to fix any messes. Not going to happen. ;-)</text>
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<text xml:space="preserve" bytes="5318">This page is intended to show advanced OGF users different ways to make detailed forest cover.
Technique using overlapping polygons
1. Draw a random-shaped forest polygon, then another, then another, until you have perhaps twenty or so. Copy, resize and rotate them all so you generate even more variants.
2. Copy and paste these at random into the area to be filled, allowing the segments to overlap. JOSM won't display the border lines so it will create the patchwork effect when uploaded. You can copy-paste 'clusters' of these shapes and with a bit of rotation and resizing they will look different.
Technique using real map textures
This section describes using isleño's technique for Gobrassanya, Suvuma and West Commonia.
| Warning: this can be difficult, time consuming, and sloppy.
It also requires a working knowledge of Inkscape vector graphics software and the JOSM map editor. It's not easy, it can take a huge amount of effort, and it can cause massive headaches. In addition, some people would say it's bad form in OGF to use textures from the real world... and on top of that, some people don't like the look of the end product. So, attempt only at your own risk. |
1. Take a screenshot of the OGF area you'll be working with, and import into Inkscape
Use it to make a general plan for where you want the forest cover.
2. Find the perfect texture and use the Trace Bitmap function to create a vector shape
Next, spend some time doing image searches to find a detailed map of forest/vegetation cover. Finding a good image can be really hard. You need a map that features really interesting textures, and shows them at reasonably high resolution, and with reasonably high light/dark contrast. On top of that, you should make sure that the map is public domain (most images produced by NASA, the US Forest Service, or other US government agencies are). For this example we're getting our texture from a public domain NASA map of deforestation in Paraguay.
Once you decide on an image, paste it into Inkscape and use "Trace Bitmap" function to create a vector shape of the image's dark areas. Then delete the image, leaving only the vector shape.
3. Cut the shape into lots of small pieces
Ideally you'll want to cut in such a way that breaks the fragments into usable groups, and minimizes the length of straight cut lines.
4. Reassemble the small pieces to form a completely new shape
This can be insanely hard. The challenge is to take the pieces and reassemble them using the screenshot as a background and your sketch as a guide. Not only that, but the new shape needs to look natural and fit with the local geography. And the pieces need to be arranged so that the straight edges where you cut are hidden by other pieces.
This step is like a crazy puzzle. It can be really hard and take a lot of time. Please do not attempt this unless you actually think you'd enjoy it. You may need to do lots of rotating pieces, flipping pieces, cutting larger pieces into smaller ones, adjusting and readjusting, overlapping them in different ways. You may even decide to import another image and repeat the previous step to acquire more pieces, or even draw a few custom pieces of your own, if you can match the level of detail.
5. Combine the pieces and export as .svg file
When everything is perfect, use Inkscape's "Path → Union" tool to combine all the pieces into a single object. Save the object by itself as an .svg file.
6. Import to JOSM, create multipolygon, reposition, resize and cleanup
Install the ImportVec plugin for JOSM and use it to import the .svg file. You'll need to resize it and reposition it in the right place... and this can be a nightmare with many thousands of objects, especially if you're working on a slow machine or if you lack the most amazing JOSM skills. Using the "Create multipolygon" tool can also be annoying, especially if there are any errors in your multipolygon (crossing paths, etc). It can also take forever to upload everything to OGF, to clean up afterwards and tweak things so they look just right, etc, etc.
So... seriously, if you have any sense, turn back now, haha.
Finally
If you have questions, feel free to ask on the talk page here, or contact isleño... but don't expect isleño to fix any messes. Not going to happen. ;-)