Blender GIS - introduction and complete workflow

so in this video i will show you how to work with gis data inside blender with the use of the blender gis add-on and make landscape visualizations like this one so the first thing you have to do is to download and install the blended gis add-on so go to google and google vendor gis and this will bring you to the github page where you can download the gis plugin go to code download zip and save next startup blender now you just have to activate this add-on go to edit preferences and in preference go to add-ons and in add-ons go to install then search the location where you've downloaded the blender gis add-on it is probably called blender gis master.zip and then hit install add-on i won't do that because i have it already installed on my computer so then we still have to activate it by searching for it in the search bar here i search blender and blender gis shows up on top i activate it by ticking this square in front of it then there's only one important thing that that we have to set up and that's the cache folder that's where it stores its temporary files so select the folder and create a new folder if you like or use any other folder that's on your hard drive already so i have one called blender case ready i select it and accept now you are set to go so the blended gis add-on added menu items on different parts of the blender interface but the most important one is on the top left side of the screen is in the gis menu with the preferences that will bring you back to the preferences that we just discussed uh and otherwise import export and other functionality of the blender gs add-on that we will discuss in the course of this video another location in the blender interface where it added some a small menu item is on the right side in this menu if it doesn't show with you you have to click on this little arrow here go to the view tab and then you see at bottom the geoscene tab and there you can set georeferencing of the scene so here you set the core basically the coordinate system in which you will be working so in this case i have it set to web mercator they're default there's another two options the wg s84 and the web mercator very widely used global coordinate systems and but you have access to the complete database of coordinate systems so if you go click on the plus and then add search you can enter here the epsg code which stands which is the identifying code of all chord of uh coordinate systems you can also simply if you don't remember the code hit a keyword like ashford which will bring you the dutch national grid so you can also work in that coordinate system however we will be working with uh map layers that are found online that are accessible through with the blender gis add-on and these are all in webmercator so we have to select also when you add new layers you get the option to select and set the cng referencing note that it is with the default settings of the standard add-on that you're working with it is not possible to work with layers that are in different coordinate systems in order to get this functionality you have to add or to install an extension to the gis add-on but this is not necessary to follow this video because we will be working only with webmercature so how do you get gis data display in blender well that's very easy well we start with selecting the default cube hit x and delete it we also close this tab to give us more space to view the maps in viewport then you go to gis and then we start by importing base map data click on it and then you have this option to select base maps from different sources from google from openstreetmaps from bing from sri which will give you various maps that are also available in arcgis for instance and uh open street and another open street maps so uh i will just show you with a google satellite and you have the option of satellite and map and otherwise everything else is set as required so you hit ok and it will automatically project you in top orthographic view the way we look at maps so initially it's 2d display and you're kind of fixed in this display and you can also see that your mouse now that the location of your mouse now corresponds to a coordinate that is displayed in the top left part of the screen so the reason that we are not seeing any map displayed is because the blender grid is in the way we're now zoomed out so far that the blender grid is very fine and is actually obstructing our view so we have to make sure that the blender grid does not display go to viewport overlays at the top right of the screen and then deselect grid and you will directly see an image of the earth if everything went right but we're not in geo s view anymore now if you zoom in you don't get any uh you don't get any higher resolution image so i have to activate it again back to your database map at the base map and now we're able to zoom in on any location of the earth you can zoom in by scrolling the scroll wheel rolling the scroll rail or by hitting b on the keyboard and you will get the cross hairs and then you can select an area and that's an area where you can zoom into uh by pressing the middle mouse button you can drag the view you can also search locations on the earth so you can and you do that by hitting g it will give you the this search bar you can search any location error that it recognizes so for instance paris and to automatically zoom into paris to switch to another base map layer you can hit spacebar and then you can select any of the other options so for instance esri shaded relief all right it takes a while to download sometimes s reserves a little bit slower than the google ones as you can see it loads the s reshade relief of northern france if you want you can pause the video now and explore what the other map layers have to offer you note that sometimes when you're switching between two different map layers that you certainly see nothing at all that either means that you haven't downloaded the map tiles yet or that there are no tiles available for that specific resolution in that case you should zoom out a little bit when you've done enough exploring you can zoom into any kind of interesting topography in my case we're moving from northern france to central italy to the small town of norma while you're looking for a location that you like i'd recommend to turn on google maps again because these tiles load faster than the s3 ones so zooming into your location i hit b and i position my view into a few covers and area that i like so when you're satisfied you can export the current view by hitting e on the keyboard that will create a flat plane a flat g reference plane of the view you just had from the on the map if you don't see anything and instead see just a grey plane it means that you're in the wrong shading mode so you can either switch to a different shading mode by hitting this sphere here or still in the shading mode you can turn on textures however you will probably notice when you zoom in the resolution image is rather poor is because you were quite far away when you took this snapshot so you get only the lower resolution tiles that belong to that level of zooming when you when want to keep the level of zooming while at the same time getting a higher resolution image you have to do the following for now delete uh the map that we just made go back into gis view hit base map google satellite so we keep the same area but we still want to zoom in on the resolution in order to do this we have to hit l and that locks the current view of the camera to this area so you can see on the top left that it is now locked however we can still zoom onto the resolution of the image so when i scroll the scroll wheel now you can see that it will increase the zoom level zoom 15 zoom 16 but you can see for zoom uh level 17 it has to download 650 tiles so this may take a while so i went back to zoom level 16 because at level 17 it wasn't able to produce an exported map um sometimes you have this because there's too many map tiles that have to be loaded and combined into a single map apparently the add-on cannot work with that so there's also a way to check whether you are happy with your resolution without zooming in further on the on the zoom level so in this case you have to press ctrl and then the mouse wheel in order to zoom in as you see it doesn't load new uh a new zoom level and associated tiles you just zoom in on what you have now and then you can see uh in more detail the resolution that you have currently so i'm all right with this and when you are as well then you hit e and then it exports the map and you can see here also in the outliner that there is an object called export google set wm so to get this into a 3d representation of the landscape we have to add some elevation data luckily the blender gis add-on provides for this as well so with the plane with the projection of google maps selected go to gis go to web geodata and get srtm and this will load the nasa satellite elevation global settlement like data onto this map and then boom it transformed the flat plane into a 3d representation of the landscape using the global elevation data you can also turn off the texture see how it looks like it isn't the highest resolution but it's okay for our purposes for now so what else can we do well let's first turn the textures on again so we can also we have also access to openstreetmap data through the blender gis head on and that allows you to plot other topographic features like houses roads etc onto your elevation map so to see how this works go to gis go to webgeodata again and then get osm openstreetmap so i have with the waste tab selected you choose building and then we choose elevation from object and then we select as object where it gets its elevation from the google exported map with the elevation data on it so this one we want our buildings to be extruded so 3d the default height is a little bit high for this kind of rural habitation that we see here so i put in a default height of 6 meters and then a random height threshold of four which allows you to randomize the height a little bit and a standard level height so of each floor of three meters as if this data is available and then we hit ok this will take a while again because it grabs the data from this online resource and has to project it on your map again so when it's finished you see that it has added small blocks of housing to your map so the blender gis add-on also allows you to visualize some other properties of the landscape other properties that are common to visualize in a gis system as well such as height slope and aspect to access this functionality you have to select the landscape because it will create new materials in order to visualize these different elements so go to gis and then to node and do terrain analysis and you will see that it has replaced the material of the terrain uh for a new one so you can see this at material properties on the right side the rust mod one was the old material that was applied to this terrain which was the google satellite imagery that's not lost we can still use it if we want to but at the current moment it has applied the height information on the on the terrain so this uh the green represents a low terrain and the red represents a high elevation and besides a height material it also created two other materials one for aspect which is the orientation of the terrain south north west and the east and one for slope or the steepness of the terrain which red in this case is a steeper slope than the green it is very easy to change the color scheme of these different visualizations of landscape properties so we're going back to height and then we're going to material properties below the surface section you find a color input which is called the color ramp and we have to open it by clicking the arrow and then you see the color ramp that is being used to visualize the elevation data in this case you can move these parts of the color ramp to change the location of the color you can also change the color itself by clicking on one of these things and then basically change the color in the color wheel you can of course also add other stops in this color ramp by hitting the plus that's one in the middle and another one and another one and these can also all be colored in the way you desire and since these color stops on the color ramp represent basically elevations they act a little bit like iso lines so when you start to move one it is like you are visualizing a moving iso isoline which is a very effective way of visualizing the change in landscape elevation in this case in a later video i will explain how to make an animation out of this and export this as a video so to finalize the workflow and complete the cycle back to gis software we we're gonna make a geo render of this image but can be imported back in software like qgis so to do this select the object that you want to make a geo rendered auto graphic image of so then you click gis camera and hit geo render this rectangle that's created here is basically an orthographic camera that is positioned exactly above the terrain looking down on it to go into camera position you hit the zero on the numpad or you hit this button here toggle the camera view this will bring you in top down view basically the fuel from the camera down on the landscape and in order to export it you have to make a render or snapshot basically of what you're seeing here you can find the render settings at the right side here so here you set the resolution of the image that you want so i'm right with this resolution that was already automatically set by the blender gis add-on the next thing you do is go to view and viewport render image a new window appears with the render as created and then we do image save s you save the image however the image is not automatically the geo reference information is not automatically included in the image but a separate file is created which includes this geo reference information open a new window inside by hitting the corner and then dragging it and change this into the text editor and in the text editor blender hit this little button and you will see that there is a file georef can wld and that's a so-called world file which includes the georeference information for the map so we have to save this file as well in the same folder as the render and with exactly the same name so save as so this is called render2.wld because we named our image render to dot png save so with a rendered image and the world files saved on your hard drive in the same folder we can open an gis program like qr gis and simply load the render into the layers and you see that it projects on the right location as long as you ensure that the projection and coordinate system in qgis is the same as you used in blender you may be wondering now why we went to this entire labyrinth process of visualizing data in 3d and then exporting it back to a 2d format well for one thing sometimes it is necessary because we want to see our data in relation to data that we only have in gis another reason is that we can do some things better in blender than in gis it is of course possible to export this model as a 3d model which i won't discuss in this video but i will show you how to make a render of this view basically a render is a 2d picture of your 3d image so to make a render you go to view and then viewport vendor image this is the most straightforward way to make a render one last thing before we wrap up this video you may have wished to replace the height material again with the google maps imagery and try to click on this one that doesn't work in fact this is now the material that is applied to the terrain and this material in this specific slot should be replaced by the rust mod one so if you want to get imagery back select the slot in which the material is there that is used on the train and then search for the rest matte terrain and then you can remove this one in the next video we will pay more attention to lighting setup rendering and camera and material settings as well as working with your own custom data so hope to see you in the next video

Channel: 4D Research Lab

Views: 41,149

Rating: 4.9161291 out of 5

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Id: u8Fg-u-VWUE

Length: 24min 53sec (1493 seconds)

Published: Fri Oct 23 2020