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.
• QGIS file(s)(optional): a set of .geojson files exported from QGIS containing the definition of polygons or points to be interpreted as NDunes objects of your choice, just like the OpenStreetMap objects. These files are optional and can be added to the OpenStreetMap files for more precision, or subsitute the OpenStreetMap file completely.
• 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 five sets of files, the right button opens an action specific to the file : either the browser where you can download your files, or setup options, etc.

OpenStreetMap File

The OpenStreetMap file is mandatory, and you can only setup one OpenStreetMap file per blueprint document.

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

QGIS File(s)

The QGIS files are optional, but can either add precision or customization to the OpenStreetMap data, or completely replace the OpenStreetMap file.

Interesting QGIS files you may want to import if you're working on a French Scene :

• The fields from RPG data base : Delimitation and biome type of each field, contrary to OSM farmlands that are very unprecise. The legend for the field acronyms can be found here.

• Buildings, landuse, roads... from BD TOPO data base : the BD TOPO is a very rich and precise data base for France. It can entirely replace OSM files. Some files are explicitely supported in NDunes and we recommand their use : BATIMENT.shp, ZONE_DE_VEGETATION.shp and TRONCON_DE_ROUTE.shp. Other files can be imported as custom files.

In NDunes, it is not possible to directly import QGIS shapefiles, they must be converted into geojson files using QGIS or another software.

The files supported by the blueprint must respect the following criteria :

• Geojson export format
• WGS84 coordinate system
• Contain geometries of type : "Point", "Polygon"/"Multipolygon" or "LineString"/"MultiLineString"
• At least one property of type String per object

Make sure to set all these things when exporting your QGIS layer into a geojson file as shown in the image below.

After importing the QGIS files in NDunes, your must open the QGIS classifier widget by clicking on the button at the right of your QGIS files, in order to convert your imported QGIS objects into blueprint objects. Otherwise, you won't see anything on your blueprint.

The QGIS classifier is divided into 2 sections :

• The parsing section
• The conversion section

QGIS Classifier - Parsing Section

In the parsing section, you will let NDunes know what QGIS files you have imported and how you want to exploit them. Contrary to Open Street Map objects, a QGIS object can represent anything the QGIS user had in mind. So NDunes does not know if a particular polygon is a lake or a forest or a sidewalk, etc.

If you have imported a supported file from the source list, just select the correct source and the parsing options will automatically be set. If you have imported a custom file, select the "CUSTOM" source. You will then have to type the "CLASS NAME" property yourself.

Once every source file and "class name" property are set, you can hit the Parse files button. The section below will then fill with all the classes found in your QGIS files.

QGIS Classifier - Conversion Section

Then in the conversion section, for each class of objects (grouped together if they had the same "CLASS_NAME" property value in the QGIS file), you can select if you want them converted as blueprint classes, and under what kind of NDunes object. Options depend on the geometry type of the QGIS object :

• Polygons/Multipolygon objects can be converted into Land Use Areas (Decal), Waterbodies, and Buildings. It is not possible to convert to sidewalk or garden.
• Point objects can be converted into Geometries or Plants
• LineString/MultiLineString can be converted to Roads.

Once you have chosen the NDunes conversion type for every QGIS object groups, clic OK and the blueprint classes will be updated instantly. They will appear in purple color on top of OSM objects.

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).

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.

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.
• Navigate to the "Blueprint" 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

Redefining your area

Once you've imported all the input data you need, you may want to restrict the area you want to export in 3D from the blueprint. For this, you have 2 options : creating an export area, and/or cutting objects that continue outside your bounds.

Export Area

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Creating an export area

If you don't define an export area, all the objects contained in your OpenStreetMap and QGIS files will appear in your blueprint view, and will be exported in 3D at generation. If your files cover an area that is too big, you can reduce it by using the export area function.

To create an export area, click on the Create button, and start drawing a rectangle in the blueprint view. All objects that are completly outside of this rectangle will disappear from your blueprint. To delete your export area, click on the Delete button. You must delete an existing export area before creating a new one or modifying it. There can only be one rectangle at a time.

Cut objects by the bounds

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Cutting objects by the export area

By default, imported objects area kept whole, and are exported as long as the have at least a portion of the object inside the export area.

However, some imported objects (especially OSM landuse area or rivers and roads) may be very big and go way beyond your area of intersest. If this is the case, it can be intersting to cut them and remove the parts of the objects that go beyond the export bounds you have chosen. To do this, toggle the "Cut Objects" button.

Blueprints

Scene parameters