Downloading and setuping the Blueprint input data.
You can setup 4 input data files to your blueprint document to generate a scene.
- OpenStreetMap file (mandatory) : a .osm file, used to generate the land areas, waterbodies, roads and buildings. This file is the base file necessary for the blueprint generation, you cannot generate a scene from a blueprint without an OpenStreetMap file.
- Cadastre file(s) (optional, France): a set of .json files, used to generate the gardens around your OSM buildings, as well as the sidewalks bridging the gaps between roads and gardens. This file is optional, if you don't specify one you can still generate a scene, however you will not have gardens nor sidewalks.
- ASC file(s) (optional, France): a folder containing the necessary .asc height maps, used to generate the terrain (primary soil elevation). This file is optional, if you don't specify one you can still generate a scene using the default flat terrain or an artistic terrain.
- Blueprint stylesheet (optional): a blueprint document in stylesheet mode, used to specify all the templates to apply to the generated objects. This file is optional, you can either specify by hand in the blueprint all the templates for your scene without using a predifined stylesheet, or even generate without templates at all and then apply everything in the 3D viewport.

Input data setup
For all four files, the right button open the website, in your browser, where you can download it from.
OpenStreetMap File
The OpenStreetMap file is mandatory, and you can only setup one OpenStreetMap file per blueprint document.
Note:
OpenStreetMap is a free, editable map of the whole world that is being built by volunteers largely from scratch and released with an open-content license.
To download your file :
- Open OpenStreetMap
- Navigate to an area of interest.
- Select Export to download an .osm file

Once the file is downloaded :
- Move it to the "Blueprints" directory below the working directory; see here: Choosing a working directory.
- Select it in the Blueprint view, by using the "OSM file:" file selector
Cadastre File(s)
The cadastre files are optional, but without a cadastre file, you will not be able to generate the gardens and sidewalks automatically from the blueprint. You can add as many cadastre files as you need to cover all the buildings of your OSM file (for instance if you have 3 villages in your zone, it is likely that you will need 3 cadastre files).
Note:
Cadastre files are free for download and availiable for all towns of France from a gouvernment website.
To download a cadastre file of one town :
- Open cadastre.data.gouv.fr
- Select the number of the departement of your town (for instance for St Witz, the department is "Val d'Oise" so select number 95)
- Select the INSEE code of your town. You can Google it if you dont know it. WARNING : it's NOT the post-code of the town.
- Now click on the archive file named cadastre-%INSEE_CODE%-parcelles.json.gz. You don't need the other files, only the parcelles file.
Once the file is downloaded :
- Unzip the archive to extract the cadastre-%INSEE_CODE%-parcelles.json file.
- As for the OSM file, copy it next to your blueprint document inside your working directory.
- Select it in the Blueprint view, by using the "Cadastre files:" file selector. At this step, you can select several cadastre files at once if needed to cover your entire OSM area.
ASC File(s)
The ASC files are elevation maps that the Blueprint uses to generate the real terrain underneath your town. These files are optional, you can choose to keep your scene flat or to use an artistic terrain that will not match the real relief of your area.
Note:
ASC files are free for download from the IGN website, constructed from a LIDAR technology, and are availiable in 3 different precisions : 25m, 5m and 1m. We advise the 5m for NDunes rendering, but all 3 area supported.
The ASC files are classified per department, so you have to download an entire department folder with all the ASC files covering the department:
- Open IGN website
- Click on the download link of the departement containing your OSM area (for instance for St Witz, select the link under "Département 95 - Val d'Oise" ). The download might take a while.
- Once the archive is downloaded, unzip it to get a folder looking like this one "RGEALTI_2-0_5M_ASC_LAMB93-IGN69_D095_2020-11-13"
- As for the previous files, copy the folder next to your blueprint document inside your working directory.
To create your primary soil from the ASC files, we have developped a tool to make it as easy as possible. In the Blueprint view, click on the light bulb icon next to "ASC files:"

In the "ASC Files" helper pannel:
- From the "ASC files folder:" file selector, select the folder directly containing the ASC files (not the root folder you have unzipped). From the the folder you have unzipped and copied next to your blueprint document, navigate to ./RGEALTI/1_DONNEES_LIVRAISON_2021.../ and select the RGEALTI_MNT_5M_ASC_LAMB93_IGN69_D095 folder. There should only be ".asc" files inside it. Do not rename those files.
- Set the "ASC file precision" to the one you have chosen to download (25m, 5m or 1m).
- Choose the area to cover, either the entire area covered by your OSM file, or a smaller "Export Area" that you can define inside the blueprint document.
- Choose the number of surrounding ASC tiles you want your terrain to cover. If zero, the terrain will only select the ASC files requested to cover your selected area. If 1, one extra ASC tile will be added around every side of your area to create a larger terrain. You can add as much as 5 extra tiles.
- Click on soil "Create Soil" icon, will automatically select the correct files from your ASC folder and transform them into a primary soil document ( see Soils ), ready-to-use.
Troubleshooting :
After clicking on "Create Soil", you could get the following warning pannel if NDunes has not found in the folder all the necessary ASC files to cover the requested area.

It can happen in two cases :
- You have selected the wrong department.
- You have selected the wrong folder (aka not the folder directly containing the .asc files)
- Your area overlaps on several departments. In this case you can either reduce your area (by reducing the number of "Extra surrounding tiles" or defining an export area), or download the ASC folder(s) of the missing neighbouring departments. You then have to create another folder next to your blueprint document, name it "95and60" for instance if you need to cover an area between Val-d'Oise(95) and Oise(60). Inside this folder, copy all the .asc files from the 95 folder, and all the .asc files from the 60 folder. Then select this 95and60 folder in the "ASC files folder" and hit the "Create Soil" button again.
Blueprint Stylesheet
What is a blueprint stylesheet
A Blueprint stylesheet (or Blueprint template) is a particular type of Blueprint document. When you create a Blueprint document, the first field you see in the view is "Generate a Scene", which is what you're learning to setup right now in this tutorial. However, if you switch this field to "Setup a template", you're now designing a stylesheet/template that will associate caracteristics to OpenStreetMap objects, as well as general scene specifications.

For instance here, an OSM land area of type "Rock" will be generated in NDunes as a decal area with a Soil document named Rocky_Soil_1. The "Bog" OSM area will have the biome "Wetland" spawn in it. For general scene specifications, we can see here the biome SparseForest will spawn in the outskirts of the scene.
How do I get a Blueprint Stylesheet ?
1) Blueprint stylesheets can be created by yourself, which means you have to :
- Create another Blueprint document, name it "MyOwnStylesheet", and switch to the "Setup a template" mode to get this doc view.
- Create all your specifications documents (soils, biomes, materials, buildings, roads...) or download them from our store.
- For each OSM object class (like the Land Use "Rock"), associate the caracteristics you want to apply to them in 3D after the scene generation (here, the soil "Rocky_Soil_1"). See Customization of classes.
- Setup the global scene parameters, see Scene parameters.
2) Or you can download a ready-to-use stylesheet from the NDunes' store. Our stylesheets are setup by artists to respect a visual coherence, as well as optimize the balance between perfomances and rendering quality in NDunes. To download an NDunes stylesheet:
- Open NDunes Store website. If you don't already have an account or a valid subscription, please follow bk_bp_store_subscription instructions.
- Navigate to the "Pack" category and click on the stylesheet you like.
- Clik on the "Download" button. (If you only see a "Subscribe", it means that you are either not logged in on our website, or you don't have a store subscription at the moment).

Once you've hit the download button, you will be invited to open NDunes : accept. In NDunes, the download of the stylesheet will begin. Downloading a stylesheet means downloading all the documents (soils, biomes...) that this stylesheet is using. This operation can take a while as there is a lot of 3D data (up to 30 minutes depending on your internet connection). NDunes will be freezed during this process, please wait and dont try to cancel the download by killing NDunes.
Now that you have your stylesheet
Now that you have a Blueprint stylesheet, you can select it using the "Blueprint template" document selector. As soon as you have set the Blueprint template, all the OSM categories and Scene parameters of your blueprint will fill up automatically.
Note that if you had already changed valus in the Scene Parameters of Customization of classes sections, they will be overriden by the new stylesheet values.

If you want to customize the stylesheet values, please refer to Customization of classes and Scene parameters. If you want to generate your scene based entirely on the style defined by the template, you can skip those two steps and go directly to Generating the scene
![]() | Scene parameters![]() |