Mapping - maperitive

[wilddog]

Hi, I was looking to start a new map and wanted to use a good set of satellite data as the source. I was used to using the 3dem data maps from a few years back but also decided to have a look and see what had progressed. Mak then stumbled across quite a nice simple tool which others may find useful and is pretty straight forward to use.

The tool is maperitive which you can down load from http://maperitive.net/. Its also free.

The tool allows you to select a map, scale it to whatever you want and export as a bitmap (.png) though other formats are also supported. This basically means you can create the same sort of data extracts that the 3dem data supported.

Steps are :
1) Download the tool, unzip and you just need to run the Maperitive.exe which will present you with a webmap (OSM Mapnik).

2) You zoom in and out on the map as usual by clicking and using the scroll wheel.

3) You then right click on the map and set :
a) Geometry bounds (of the area you are interested in).
b) Printing bounds..within the Geometry bounds... of the map you want to print. You can readjust these later.

4)Type in the command prompt box (at the bottom of the screen) "generate-hypsometric ramps=0:black;1500:white" without the quotes.
you can change the values here as this is setting the greyscale values eg the valkue above will set 0m as 0,0,0 (RGB) and 1500m will be 255,255,555 (RGB). Obviously depending on the area covered you may want to use higher or lower scales.
Then press return to run it.
This will generate a relief image map from SRTM3 data which is indicated in the Map sources box on the right hand side of the window.

5) In the Map sources window (on the right side) you can toggle on/off each map layer by clicking the little yellow star.
as the OSM map is on top you need to switch that off to see the greyscale map!

6) You can now zoom in or out which sets the 'size' of the maps.

7) In the tools option you can generate the bitmap using the export to BITMAP command.
When this command runs it tells you the zoom level and the bitmapsize. If too large or small then just adjust the zoom

8) the file is output to a file in the maperitive folder called output. Just copy it and rename it before doing any further exports or it will over print.

there are some other map options which may be useful for generating the radar map as they have relief settings (hill shading etc). You just need to generate these also before you come out.

The data is based on SRTM3 data so you can generate very detailed maps of small areas as most of the data is based on approx 90-100m distance points at the equator. So is much finer than the older satellite data.

Only caveat. If you are silly and try to make a very detailed very large map its pointless as the game won't support it and the memory will likely be too great for you computer.

I should add the site does include tutorials and documentation for the tool as you can do a lot more with it.

[Gigantus]

Busy trying it now - I am wondering how\if it will possible to generate 'flat' maps with rivers for map_features.

the value above will set 0m as 0,0,0 (RGB)

That could be a pitfall if the value isn't changed as 0,0,0 is generated as sea. Would it be possible to set the value to -1, eg "generate-hypsometric ramps=-1:black;1500:white"? Or is zero water?

Edit: curse my slow connection, it takes ages to download the SRTM3 tiles, and I am just doing England at 1:6.000.000

Edit2: It's done! I replaced the 0,0,0 value with blue and have to figure out now how to recreate a proper coastline (see the Southeast coast), a problem I have come across with 3Dem as well. Probably use the 'regular' view as overlay. Otherwise the detail is great. The grid is surely some simple setting, so I am not worried about that.

[wilddog]

Hi
A much simpler method to know the 'existing' coast would be to generate an identical map with one of the map options that uses the same color for the sea. Then simply use it as a layer to generate.
That wouldn't give sea depth though... I would need to check if you can pick that up by using a larger negative number although in the end I normally edit the sea values anyway.
The grid is a switch on/off flag in the menus.
As is the scale which shows up at the bottom.
There are also a few od pixels which show I think as white where no data is available (there are a couple by Cader Idris in Wales).

Rivers need to be hand drawn to ensure they follow appropriate contours and comply with the region size mapping rules in terms of how each pixel on the features map is connected. You can see them by taking a layer of the one of the other maps so not a big deal really.

[Gigantus]

Creating rivers was a bit easier with the tool I am using at present, but it had other drawbacks, particularly at large scale (multiple continents) maps. I'll experiment a bit further and see which one suits me better.

[wilddog]

I was thinking of making my own tool for some of the map bits. Originally to add to IWTE but might create as a separate tool. It was more to handle some of the basic steps I used to go through when creating a map and speeding a couple of them up. I may have a look at the rivers bit associated with that.

[Gigantus]

While you 'tool' this could you also have a look at the steps to create a map suitable for the radar map display, eg basic features with hill shading?

[wilddog]

You can generate a map with the hill shading from this already. Just by using the other map options and turning on the layers. It is something I was going to look at though.

[wilddog]

Reading a bit more on the documentation it should be possible to create a map with just rivers to use as the basis for the map features. I just need to figure out the right rule set to apply to the data for doing this. In the meantime I started knocking up a little tool to read in the various map files and overlay them and create a 3d height map from the map_heights. I'm mostly after this for the initial creation of those map files rather than trying to create a descr_strat.txt file.

[wilddog]

Unfortunately, Takes too much memory and downloads to extract the OSM data. after various attempts I decided its better to give up on the river and coastline bits unless you ant to do it as separate smaller downloads. Will likely just stick with maperitive for the heights bits and then use other maps (you can download) as the basis for the coasts. Doubt I'll resort to the demis map. While that had the nice features regarding the toggle of waterways and coasts (switch on and off). Its a little naff for a detailed map as it is missing the height detail for more localized maps (which was what I was after).

Separately decided to make my own tool for maps (as in amending/painting).

[wilddog]

I was back looking at this today and decided that probably a hypsometric scale of "generate-hypsometric ramps=0:#000000;1:#010000;550:#FF0000;1100:#FFFF00" (see first post) is actually best. This means any 'corrupt height data' which defaults as RGB 255, 255, 255 is relatively easy to identify. Note the 550 and 1100 values are simply mid and max values for the heights map you are creating data for and should in the end be used to set an HGT value of 1500 and 3000 respectively.

Next IWTE version will read specific hypsometric data and reinterpret back to an HGT file. The data will still have issues around the coastlines so you still need to do some corrections there particularly to reset the 'odd pixels' in the map_heights files correctly for game use and region creation.

[wilddog]

OK finally decided that using the command

generate-hypsometric ramps=0:#000001;1:#000000;2:#020000;550:#FF0000;1100:#FFFF00

gives the best results. The 550,1100 values should be converted to half and then the maximum height value you want.

IWTE_v14_11_A supports reading this in and converting to an HGT file. If you then want to lose the extra details IWTE also allows you to reload the HGT file and cretae a standard heights.TGA file from it.
Additionally IWTE applies an algorithm for correcting corrupt pixels (as best it can). Once loaded in IWTE you can then use a color scale like 'NEmaphgt' to better view the hgt map for further editing.

The load function in IWTE is via the selections : file Type -> Strat mapping Files -> Map Heights -> Import map to HGT -> IWTEscale