[RELEASED] CityGen3D - Procedural Scene Generation From Real World Map Data

Hi,

Do you mean not appearing after Processing on 2D Map, or appearing in 2D but not getting generated in 3D?

You may just need to adjust some settings. Please can you give me a specific example.

 

I think they are not appearing after Processing on 2D.
For example I take this: (pic. 1)

In OSM2World I can see all the buildings in 3d: (pic. 2)

But in Unity not all of them are appearing after Processing on 2D: (pic. 3)

And accordingly they are not built in 3d: (pic. 4)

 

Thanks for the detailed info. Please can you confirm Latitude and Longitude of this location?
I think the most likely cause is that the buildings are tagged in a way that isn't getting picked up by the default profile.

 

Latitude: 55.69513
Longitude: 37.84138

can the profile be changed?

 

I had assumed the buildings were not tagged with one of these settings to match them up to defined CityGen3D building types:


However they are tagged fine (eg building-apartments). Had they been tagged with something not listed you can easily add in your own and Process again, as is the case with other map objects.

In this case it's a bug where CityGen3D wasn't correctly identifying the shape of the buildings because they were made up of several ways in a relation. I have fixed this for v1.02 (see screenshot below)

If you email me I can send you a fix ahead of the update.
Thanks for reporting the bug!

 

This weekend I'll be working on a tutorial video showing how to set up CityGen3D for scene streaming larger environments.
As a teaser, here's a few screenshots of the generated environment covering a part of Central Park in Manhattan:







Everything procedurally generated using CityGen3D default materials and prefabs.
When I can get round to it I'll add a few more building material variations for the taller buildings.

But even with the current defaults, I really like the juxtaposition of the skyscrapers and parkland

 

Hi! Is it possible to make a prefab from the generated buildings? Now the mesh component is lost when creating a prefab.

 

Probably the easiest way to do this without any coding is to install the FBX Exporter from the Package Manager.
This will allow you to save the mesh and then assign it to the Mesh Filter of your prefab.

 

Minor bug report: generating say a 4*4 set of terrains to be saved as scenes, the naming of the "0" set needs a left zero pad on the numeric to properly match the naming convention - i.e. 000, 001, 002, 003 instead of the 0, 1, 2, 3 shown.

 

Hi,

Coincidentally there'll be a tutorial video out today explaining the naming of the Landscapes and how it's linked to the Axis setting as part of the Landscape Manager tutorial.

If you know you only want a 4x4 area you can set Axis to 4 and your Landscapes will be named "0" to "15".
This is because Axis effectively means how many tiles you can generate in total on one row.

A default Axis of 100 means you can go on to generate 100x100 terrains, so hypothetically you could go all the way up to Landscape 99999.
So if we were to apply leading zeros we'd have to name them 00000, 00001, etc.

Therefore it is intentional the way it is, its just not obvious why.

 

As promised, the new video tutorial shows how to start your CityGen3D project and use the Landscape Manager to create large open world environments that are loaded in at runtime using Unity's asynchronous scene loading.

I hope it proves to be a useful reference, but if something isn't clear please let me know and I can elaborate further, as well as cover additional topics in future videos.

 

I don't see these sidewalks(with curb,drain&mesh) in the Generator's Highway tab. Am I missing something? I can't find it in the other tabs too. Wish to have the ability to atleast change their materials.

 

Hi,

The Sidewalk Texturing Rules section of the Highways tab can be used to specify a material to use depending on the surface type under the sidewalk.
In the absence of any matches, the sidewalks will be textured using the terrain texture at the same location.

So let's say I wanted all sidewalks in Residential areas to have cobblestone paving.
I'd add a seamless cobblestone material to the Sidewalk Materials list;
Then click [+] button to add a new Sidewalk Texturing Rule;
Select Residential from the Surfaces drop down for the new rule;
Select the cobblestone material from the Materials drop down for this rule.

Then Generate Highways would apply this material to any sidewalk in a Residential area.

 

Thanks for the previous reply.
Another question, do we have the ability to control trees' random rotation & scale?

 

Hi,

Not that the moment, but I should be able to expose a random size range per tree type in much the same way it already is for terrain detail objects on the Detail tab of the Generator.

Edit: It actually looks like I started to hook this up during the Beta with size sliders on the Data-Trees window. But I don't think they actually do anything yet, and as I said above, I think it's better to have this configurable as part of the Generator anyway.

Leave it with me and I'll try and sneak a proper solution into this months update

 

I had a quick look at this, but I'm getting strange results with the Unity terrain tree size range system, which is what CityGen3D would interface with.
If I change the Tree Height range slider on the Paint Trees tab of a Unity Terrain component, only the auto generated billboard changes size when I paint the trees. The actual prefab remains at default size.
This reproduced in 2019.1.1 and 2019.4.9.
I'd be very interested to hear if this behaviour can be reproduced by anyone else!?

 

I haven't noticed that particular trees issue, but on the subject of trees/details/features, I have been looking at the performance hit in those areas recently using the Frame Debugger etc.

The terrain tree/detail settings are as you'd expect and the normal judicious adjustment of distance in the terrain works there. I did notice though that there's no LOD billboard for the provided trees, which isn't a huge issue as we can obviously add our own trees in, but might be worth putting in.

A more noticeable hit is the Features. For one thing, they don't appear to be optimised in terms of shared meshes, as the scene size is extremely inflated when those are included - see here where if I deleted Features from the landscape, it shrinks to 20% of the size:



I believe I have narrowed down the culprit (in my test scene at least - there may be other feature types with the same issue that weren't in this scene) to the hedge.obj being created as clones rather than sharing a mesh - I'm guessing you do some vertex adjustments for randomisation of each hedge segment as the reason why the meshes differ, however that will turn each segment into its own mesh. To confirm this, I went through a copy of my test scene and manually swapped out all the default(clone) meshes that were created with just the base prefab default mesh from the obj - and that brought the scene size (and draw calls) down considerably.

Would it be possible for a future release if any Feature or other objects creating mesh clones could instead be fixed to a single shared mesh (perhaps a shader could be used to keep the vertex randomisation) as that will really help with size and draw calls. LOD groups and billboards on those highly spawned features might also be good - for example the chain link fences do seem to successfully share a mesh but LOD culling or billboard reduction in general may still help there in terms of overall performance.

Most of the other generated objects such as buildings and markings seem to be fine in terms of contributing to the scene size bloat, with the rest of that remaining 100Mb largely taken up by terrain detail and trees by the look of it. Not sure if anything can be done there to bring it down further, although I did notice some of the foliage gives DisableBatching as the reason for draw call non batching.



I haven't messed around with terrain optimisation enough to know if that's anything you can fix or is a limitation of the Unity terrain shader in general, but I thought I'd mention it as it seems to be the next bottleneck after the hedges. Anyway, the terrain tree/detail distance sliders can cope with performance side of that, if not the scene size.

 

Thanks very much for the information.

There are two ways Features (map objects defined by a series of points) are created in CityGen3D.

The first is to Extrude a mesh along the path. This is for things like fences and walls and does require modifications to the mesh.
The second is to Clone the mesh. The intention here is to not modify the mesh so all instances can be batched together.

In the case of the hedge prefab I think you have identified an issue with the way the prefab is setup. It currently has a MeshExtrusion component attached to it, which is not needed in the case of cloning and shouldn't be present.

I'll sort this out for v1.02, but in the meantime if you remove that component from the prefab (before generation), you will hopefully find that all hedge meshes are identical after being spawned.


Although the current Detail and Trees panels of CityGen3D interface with the Unity terrain foliage systems, it doesn't seem to be an area that gets much attention by Unity.
So I have also experimented a bit with my own GPU instancing solution to foliage, so it's possible something will happen in this area next year.

Short term focus on this area is on an official integration with Vegetation Studio Pro, which will appear this autumn.

Aside from that it is already possible to use assets like GPU Instancer with CityGen3D generated terrains just with normal workflow for that asset. I've done this before and seen good performance benefits.
It just takes the Unity Terrain foliage (that CityGen3D spawns for you based on your rules), and then takes over the rendering of it using GPU Instancing.

 

a few questions, can the scenes be exported out as static to be used afterwards ..

This way users can say build there scenes, and bring back say into a 3d software to edit, iterate, or what ever...

Also can modular buildings, be used ? I assume so since you allow custom prefabs for users.


Can we import our own custom height maps?

 

part of my question above, about being able to export, so users can handle the streaming them selves or with another solution.

 

Hi,

There's no custom made export tool, although I believe some users have used third party terrain exporters and the Unity FBX exporter from the Package Manager to export CityGen3D generated content to 3D modelling apps.

Yes, you can hook up your own prefabs for use with CityGen3D's spawning systems. A few simple house prefabs are included for demonstration, but you could substitute these for your own modular buildings.
(There's also the procedural building system that can generate simple buildings from OpenStreetMap data).

CityGen3D generates Unity terrains and you can modify the heightmap in any way you want to as normal, if you don't want to use CityGen3D real world height-mapping system.

 

CityGen3D is now included in the extended "Reboot 2020" sale!!!
Reduced by 50% until 30th September

 

Got a question regarding heightmaps before potentially buying the asset.
In the documentation it states that

.
My question is does this allow me to use an existing terrain that I created and modified with other tools to be used to generate the other content on to using CityGen3D such as the roads, houses etc?

 

Thanks for your interest in CityGen3D.

The only thing that distinguishes a CityGen3D terrain from a normal Unity terrain is that it will have a Landscape component attached.
So you could generate plane terrains in CityGen3D (which is very quick), copy this component over to your custom terrain, and then remove the temporary one and put the custom one in position.
As long as you ensure your custom terrain is in the Landscape layer, then CityGen3D wont know it didn't create it and you should be able to generate roads and buildings on top of it.

You'd have to ensure your custom terrain size was the same size as your Terrain Size setting.
CityGen3D wont expect any individual terrain to be greater than 1024 metres.

Only other thing I can think of to mention is that CityGen3D uses quite high heightmap resolution, at multiple of 2 (+1) versus the size. So you'll want a 1024m terrain to have 2049 heightmap; a 512m terrain to have 1025 heightmap (etc) for best results.

So while your suggestion doesn't fall within the normal workflow, there are likely ways round it if you want to experiment with that.

If you do try it and run into any issues, please let me know as I'd be happy to look into the possibility of improving support for this type of workflow in future updates.

 

My 2 cents for those asking about external height maps. I bought CityGen3D a while ago, and before that I was messing about with various prototypes of my own to do with loading open data DEM maps and road/building footprints into Unity. CityGen3D appealed to me as a purchase largely because it allowed me to offload the work of constructing scene elements from those DEMs. Two of the more commonly used DEM file formats I've had success with bringing over from my prototypes and into CityGen3D are ASC files and GEOTIFFs. I've also managed to load in alternatives to OSM data, such as KML files, GPKG, and even an MBTILE. Every data source is different, of course, but once you've got one importer working you can build on from that next time. Once you've pulled in your data on top of the existing CityGen3D data (you'll have to manage the right sequence, of course), then I can confirm that CityGen3D does respect and retain any heights or roads/features/footprints that you've added and will process them correctly.

So if you've written your own importers and/or got your own height maps already (remember you can export/import terrains as raw from the terrain settings, if that helps), then the only tricky part is getting the perspective and coordinate reference systems of your new data to line up exactly with the landscape SRTM data used by CityGen3D. At first I was doing my head in with the maths there, but now I use the GDAL plugin (you can find it along with C# wrappers on nuget) and get that to do the heavy lifting by simply passing it each point from my imported DEM and converting that to the WGS84 CRS that CityGen3D uses. Then a little maths to find the right index in the height map array corresponding to that lat/lon, and you have your finer detail.

Why would one bother with any of this, some might ask? Because the SRTM data has an accuracy of 30 metres. It's very good at covering the whole world, but 30 metres between each elevation point does not capture a lot of the finer detail, and the smoothing/flattening features in CityGen3D do help but can only take things so far. See below a scene I was working on recently covering a part of London, with the base SRTM on the left. The right-hand image is the same terrain at a DEM accuracy of 1 metre, sourced from the UK DEFRA open data portal. (Some parts of Britain, you can get 50cm or even 25cm accuracy in some places!)



This is from full distance away of course, and the closer you zoom in the editor the more obvious the fine detail distinction becomes. That slash in the middle is because the DEM itself has a NO_DATA segment (typically an area missed by the LiDAR survey - no survey is ever perfect) as can be seen here in the black banding on the GEOTIFF at the bottom:



I'll likely write an extra step at some point that backfills any such NO_DATA values with a fallback to the less accurate SRTM value already present, and then the heights will be about as good as can be achieved, ready to move on to the next step of generating data. And there again, while the OSM data is generally good enough for most places, as it's entirely volunteer-driven it will typically have gaps, errors, and omissions, which I've found can often be resolved by substituting government open data. So far I've sourced high quality open data for London, the City of Melbourne, and New York, for example, as replacements for Open Street Map data, and successfully managed to get CityGen3D to recognise that data when I substituted it for the roads and building footprints produced by OSM. I don't have an image to share on that, but I believe I posted one back on the beta thread that showed the significant difference in accuracy.

So yes, in conclusion there's definitely ways of building upon the base CityGen3D functionality by bringing in your own data and additional logic, if you know what you're doing. It's not easy, of course, but certainly a lot less effort to use the power of the tool to handle the bulk of the work than to write all of that functionality yourself, in my opinion.

 

Thanks for taking the time to write this, and for all your additional tests and experiments.
It's really cool to see the tool being used in lots of exciting ways!

 

Thanks for your very detailed replies regarding heightmaps.
This definitely gave me some insight I was looking for.

I would have assumed if the plugin can generate a new heightmap using perlin noise it wouldn't be far to having it read in a texture as an external heightmap too. But since I have no expertise in this field this assumption was probably completely wrong
I think I will give it a shot regardless sometime this weekend and see how it works out.

 

The Perlin Noise implementation is good because with just a few settings you will get a seamless heightmap regardless of how many terrains you generate.
But it is very simple and largely just a fall-back option in case you want to quickly prototype without getting real world data.

Importing images for height-mapping would give more control, but requires a bit more manual work.
I think Unity still has a RAW heightmap import function, but it's been a while since I looked at it.
So up to now I've just assumed that anyone wanting custom heightmaps will just use the existing Unity Terrain tools (brushes, stamping, RAW import, etc).

But for sure, have a play with the tool and see what you think. I'm definitely open to suggestions about future improvements in this area to make it easier to support custom heightmaps, especially as I want CityGen3D to be a cool tool for building fictional worlds, as well as those based on real data.

 

Maybe I'm just understanding things wrong because of my lack of knowledge in this field.
I was mainly trying to figure out if I can use an existing heightmap for CityGen3D to generate roads etc according to the manually painted layout within CityGen on top.
The idea behind this was to for example create a terrain in GAIA, go to CityGen3D and paint a street layout, rivers etc with the custom map workflow and then have CityGen3D do its generation.
The approach you explained earlier by manually replacing the terrain and adding the Landscape component as well as putting it on the Landscape layer sounds like it would result in exactly that unless the landscape components functionality is to later modify the terrain in some way.

 

Yeah we may run into one or two issues just because it's not a workflow I've tried before.
But GAIA compatibility is something I'd be interested in supporting in the manner you describe, so if you do run into any issues please let me know.

But I think you will get best results if
1) Add a landscape component to your GAIA terrain
2) Make sure its in Landscape unity layer
3) Make sure each GAIA terrain is same size as what your CityGen3D terrains would be had it generated them for you
4) Use a heightmap resolution equivalent to ( Terrain Length x 2 ) +1

 

Just a quick feedback on the workflow for using CityGen3D with custom terrain.

Definitely possibly to do with the described workaround above and certainly not too difficult. A more tailored workflow would definitely help but most important is that it does work
To be able to see your custom terrain while painting the contents in the map view it has to be on a layer that is seen in this mode as it automatically hides all unwanted layers.
I put my terrain on the "Map Road" layer during the painting process and back on the Landscape layer once I was done painting.
Putting it back is very important as the generation process will not work otherwise.
In the generator I disabled the actions for generating the terrain(s) and applying the heightmap.

I can definitely recommend the asset for custom maps.
I'll be looking more into the asset when I have the time and will be providing more detailed feedback as well as writing an asset store review but I'm already satisfied with my purchase after having spend a couple hours on testing it out.

Stellar product

 

Thanks for the feedback, it's great to hear that you are enjoying using CityGen3D!

Up to now focus has very much been on getting real world solutions working, but I'm interested in improving the tool with regards to custom mapping and third party integrations over the long term. GAIA + CityGen3D workflow is definitely something I want to experiment with more when I can. So it's very helpful to hear how people use CityGen3D, or would want to use the tool, so I can plan future improvements.

 

The latest update (v1.02) is now available.
This is mainly another bug fixing and optimization release, but it's definitely worth updating when you can.

• Improved scene streaming performance.
• Fix for highway levelling causing seams at terrain edges.
• Fix for Surface and Building map processing with some complex relations.
• Fixed rare OverFlowException on creating some meshes.
• Building plan and blueprint reorganization ahead of further improvements.
• Improved rendering of road marking decals at distance.
• Fix for Run Generator command so it only actions on Landscapes that are related to currently loaded 2D map data.
• Fix for hedge prefab causing Feature generation issues.
• Improved Find button functionality on buildings.
• A few other UI fixes and usability improvements.

(Note that the new Buildings chapter in manual is just the start, there's a lot more in draft that will be included in next iteration of the manual, but I'm making some changes to the backend there to make it better, so need everything to marry up first).

Development focus is on HDRP / URP so there should be more news on that soon.

 

Hi. I'm trying to get this going on the Oculus Quest. Framerate is very low, around 25FPS. I've stripped down the city to roads and trees, still low. Also changed the build settings to Very Low. Any help to get this going?
Thanks

 

I think Unity terrains in general are likely to be unsuitable for Oculus Quest, because they are heightmap based.
But I'd be interested to hear other people's opinions on this, if others have got Unity Terrains running well on Quest.
Presumably if you turn off terrain rendering the frame rate goes up quite a lot?

You can try a higher PixelError setting on the terrain component, but realistically I think you may want to explore conversion of Unity Terrain after creation into a low poly mesh terrain.
I've purchased MicroSplat's Terrain to Mesh solution with this in mind, but haven't had chance to try it yet.

 

Thanks. How do I turn off terrain rendering?

 

If you click on a Landscape and go to the Terrain component.
Locate settings (gear icon) and uncheck Draw in Basic Terrain.
This should disable terrain rendering which will help us profile whether that's the main cause of FPS drop on that device.

 

Yep, that's it! Thanks for the help. FPS jumped up to 72. I may look at MicroSplat and see what it can do.

 

Yeah I recommend Microsplat in general.
The base shader is free and increases performance on most if not all platforms.

I envisage offering an alternative low poly workflow in CityGen3D next year. I already have commitments to work with non Unity Terrains workflow, so it’s inevitable progress will be made in this area over time. I’ll keep you posted when I have more news.
(So I cant promise a quick solution but it is on the radar).

Just as a side note I have done tests in VR on the Rift and that was very good, but the Quest is particularly sensitive to poly counts compared to most other modern platforms (where you tend to worry just about draw calls). So heightmap terrains are really tricky on that and would clearly benefit from an alternative workflow.

 

ya I have my own exporter, I just wanted to be sure, there was not something preventing this..

 

fantastic, thanks anyways but ya I been a professionally 3d modeler, artist/Programmer for nearly 3 decades, so I make my own procedural stuff in Houdini, Modo etc. I just wanted to be sure I could use this... since the placement of making cities is what interest me. I have a tool like this in Maya, but it don't do half of what yours does. So I wanted to leverage your tool for building towns and such with my own models, modular, procedural and my own height maps, textures, etc. ( This tool could save me a hella of a lot of time..) Money so it looks it could work well for something i'm making....

So thanks a lot.. what worried me was no source, so when this happens I wanted to be sure.. as i'm not a hobbyist. and would like to be able to use it long term. ( I normally only buy assets from people I know, due to so many disappearing... So that always worries me when I see no source. but it looks great, I may give it a whirl...

Thanks again and nice work... it looks fantastic...!


PS: is there any sort of API? not a big deal...if not.. just curious.

 

Yeah I completely understand, so I'll try and put your mind at rest.

CityGen3D has secured funding for a long time, so I'm not going anywhere.
I've been working on the tool since the prototyping stage around 2016. From January next year I'll also be working full time on the company, leaving my current games industry role. So if anything, the future should see a faster turnaround of features and fixes. Lots more exciting stuff around the corner!

Focus up to now has been on getting a workable UI so CityGen3D can be used without any coding at all.
However if you are a coder you can very easily access the processed map data to do some cool things, such as hook up third party assets.
After HDRP release, the priority will be on demonstrating the API more thoroughly through official third party integrations such as Vegetation Studio Pro and BuildR. (These will be open source, serving as examples of how to use the CityGen3D API).

 

Hi is there a problem at the moment with the login auth on the website? I am unable to login with my usual credentials to get the current update.

 

I was able to log-in ok and access the Download page.
Do you get any error message?

 

I'm getting a "Wrong email or password" error. I use a password manager and nothing has changed since my last login though, so it's odd.

 

Yeah that is a bit strange. The only thing I can think to suggest is to follow the Forgot Password link and see if you can set up a new password on your account.
If you still can't get in after trying that please let me know. Thanks.

 

Ok I did that and it seems to be okay now. Cheers!

 

bought ty.

 

Hi,

You need to install the required packages before importing.
Please try a new project and install Burst, Editor Coroutines, and Post Processing from Package Manager.
Then when you import CityGen3D all should be well.
Please see manual for more info.

 

Hi, CityGen seems amazing. Can't wait to get it.
But i have some questions:
- Is possible to scale down/up the final result? I mean, i don't want my players walking miles just to get from one point to another xD
- Any plans to integrate with EasyRoads?

Thank you in advance