heerco - I’m glad you got this working. Just a heads up that ModelInstanceCollection is marked private so it is not part of the public Cesium API and may change from release to release.
heerco/Sean - if there’s addition ModelInstanceCollection discussion, please start another thread so this thread can stay focused on 3D Tiles news.
Thanks,
Patrick
Hi,
Is there a way to store the feature-wise properties for a b3dm file to another file and use that file when rendering the batch 3d models?
It can be named as 'External' batch table.
The rationale for it is as follows:
The 3d building model is relatively constant. (so does a few of the properties - for example, the height of the building) But some properties of the building is not so constant.
For example, let's say we must color the building according to the specific day's mobile RF quality. One day the building is colored red, while another day it can be colored redish-yellow.
We cannot bundle such data (RF quality) into the b3dm file as an 'internal' batch table with the 3d models since the cost of creating the files and the storage it takes are not justifiable, since there are many such KPIs like RF quality and we must handle many days of the KPI values. Simply we cannot duplicate the 3d model with every KPIs x days.
So, it would be nice to separate the information in the b3dm file into two category. One is constant (like the 3d models) and the other is variable. The variable parts can be created on-the-fly by quering the DBMS (and cached on the server for performance) and downloaded to the web client, and then merged with the constant part - and then be drawn.
Hi, we have received this suggestion a few times and I just opened an issue for the 3D Tiles spec: https://github.com/AnalyticalGraphicsInc/3d-tiles/issues/136. In the time being you may be interested in the alternate solution suggested there.
Thank you!
I'll watch the issue!
Hi
I have a very high resolution DEM and corresponding image. Both are in TIF format but I also have them in other formats: xyz, las.
Now, how do I begin to get started in converting to b3dm tiles so I can render with cesium b3dm tiles in a browser - like say the amazing cesium-bentley example of Marseille ?
https://d3h9zulrmcj1j6.cloudfront.net/Marseille_Cesium/App/index.html
I've done a lot of reading but can't seem to find something that would get me moving with my particular dataset!
Many thanks!
Paul.
Paul
Hopefully I can save you a bit of time.
At present there appears to be plenty of reading, presentations, demos and samples. But that's it.
There is currently no software available in the public domain that would take your own data and convert to or generate Cesium 3D tiles.
To be honest, I wish this was made a bit more explicit because I'm sure you're not the only one to have invested time in looking.
Good luck!
-S
Hi all,
I am new to 3D tiles development and want to generate b3dm files. When I open a b3dm file with editor, it shows junk text so can’t figure out any way to check what’s actually written in this file. How this file is generated?
What is the format of this file?
Any help is much appreciated. Thanks.
Hi MP,
Here you can find some info on b3dm
https://github.com/AnalyticalGraphicsInc/3d-tiles#are-3d-tiles-specific-to-cesium
Regards,
Toni
Hi MP - b3dm is a binary format - in addition to Toni’s link you can also check out the b3dm spec: https://github.com/AnalyticalGraphicsInc/3d-tiles/tree/master/TileFormats/Batched3DModel.
Also… we are getting close to finishing a project that generates simple 3D Tiles tilesets like those in the Cesium samples. Once this is ready it should be more clear what steps are involved. Keep an eye on https://github.com/AnalyticalGraphicsInc/3d-tiles-tools/tree/master/generator
Thanks Antonio and Sean,
I read in some forum thread that the b3dm and i3dm files are gzipped and for viewing content you need to rename it to.gz and extract and then view. Are these files still gzipped? I am unable to see its content even after extracting them.
Really excited to see my project with 3D tiles. Can these tiles files be generated programmatically?
Ah sometimes you’ll find tiles that are gzipped but that’s not a requirement. After being extracted the content should be all there, but its in a binary format. You’ll know its correct if the first 4 bytes spell out ‘b3dm’.
I’m not completely sure what you mean by generated programmatically, but usually you would want to start with a glTF model since that is the core component of a b3dm tile. You can also generate the tiles purely programmatically based on a noise function or something similar but the internal format is still glTF.
Thanks Sean.
To create programmatically i mean to generate b3dm file from coordinates, just like we can create CZML files if we have coordinates to be drawn.
Ok I see. B3dm isn’t really designed to be generated at runtime - at least not in Cesium - since it typically represents static 3D model data.
Hi,
Does a CityGML to 3D tiles converter exist somewhere?
JS
Hello,
we do have a commercially available CityGML to 3D Tiles converter.
If you are interested, you can me.
Jannes
Nice, will consider. Though, is there any other converters to convert CityGML to 3D Tiles (tileset.json and b3dm)?
I've seen 3DCityDB and it seems it requires a oracle or postgres DB, is it really necessary for 3D tiles streaming? I'm not really knowledgeable in this.
Thanks.
JS
Hi JS,
The opensource 3DCityDB solution can only export a gltf dataset.
Our converter also requires the 3DCityDB, after you import your CityGML data into the database you can use our converter to export a tileset.json and tiled b3dm-files. The converter will also create texture atlases and can be used to reduce texture resolution.
The tileset.json Datataset is then independent from the database.
At the moment we are working on making the exporter independent from the database so that you can optionally just provide a folder with CityGML files.
Also if this is an option for you we can also convert your data as a service.
Best regards,
Jannes
Hi Jannes
Did you mean virtualcityWAREHOUSE?
在 2016年12月15日星期四 UTC+8下午4:27:27，jbo023写道：
Hi 3D Tiles folks,
We had a great discussion in the Cesium in 2017 thread. The plan for 3D Tiles is to finish the spec and Cesium implementation for a Cesium Community Review period by the end of March, before we submit for the final OGC votes as part of the OGC Community Standard process.
For the review period, we’ll have:
Also, 3D Tiles will reference the upcoming glTF 2.0 spec so we are making a lot of progress there as well. Cesium will still support glTF 1.0, but we’ll suggest that you update the glTF in your tiles to 2.0 once it stabilizes. Stay tuned.
How can you help?
Thanks!
Patrick
Hi everyone,
I’m relatively new to 3D Tiles although I’ve been working with them on and off for almost a month (nothing fancy, just a 3DTile generator from our own geojson files).
While looking at some of the 3D Tiles TODOs I saw mentions about massive models like the boing one and it made me decide to write you about something I’ve been thinking about.
I’m one of the authors of Interactive inspection of complex multi-object industrial assemblies published on Computer Aided Design on 2016. It’s main goal was to visualize complex models and being able to select even the tinyest object on the model to get additional information. One of the models we used to test the method is the Boeing model you mention on the Massive Models readme on Github with very good results. This paper uses a technique the research group I worked on developed called Omni-directional Relief Impostors or ORIs in short. There was another paper called Visualization of Large-Scale Urban Models through Multi-Level Relief Impostors and published on the Computer Graphics Forum in 2010, where it was applied to massive cities visualization. It was tested with all the city of Barcelona with very good performance results.
I’m sure something like this can be used to draw low LOD tiles reducing the geometry budget wasted on them and maybe increase the high LOD ones.
I know you guys are working on finishing the spec (will have a look at the open issues to help!) but I think it’s worth a look for a 3D Tiles v2 
El dissabte, 21 gener de 2017 18:04:43 UTC+1, Patrick Cozzi va escriure: