After touching CE 2011.1 for a while and practicing some clips (small models and samples), we plan to move onto a real project, that is, generation of 3D scene for one of our communities (6 by 6 KM) . But, we are still not quite clearer on proper data preparation/ import/ folder structure. So, we are seeking your advices from the beginning so that we can correctly set up an operational project to create this 3D scene. (Honestly, within the documentation, many of its CE terminologies are quite different than what we are familiar with).
Currently, we have DEM (TIFF) & airphotos covering this community (TIFF), many 'building' photos for texturing, roads and building footprints. We would like to start with those data to 'import' into CE project. The questions mainly focus on the file preparation and (folder) infrastructure:
How big size for each imagery/airphoto data file we should prepare for ???import???? 1 GB, 100 MB, or 10 MB? Is the format TIFF suitable enough?
Should we consider ???images or airphotos??? as ???surface??? texture when ???import??? DEM into CE? If not, how can we prepare ???surface texture??? overlaid onto DEM for the scene generation?
Where (which folder) can the ???building??? textures (photos) be put? What kind of texture photo formats should be organized?
2D roads & building footprints' shapefile: which type of road shapefile is suitable (polylines or polylines)? If regular shapefile not suitable in CE project, do we have to build ???road network???? Where is the road shapefile put in CE project? Any advice for editing attributes inside those 2D shapefile so that it is easy to transform into 3D?
With CE 2011.1, how can we set up the projection /datum (saying, UTM 35/WGS 1984) in the CE project? (As recalled, the trial version can set up initially, but couldn't find out the place to do within the release CE 2011.1. Missing something)
We expect that we can start to redesign this city with CE, once all those are imported and set up properly; and eventually we can get the 3D scene for this community featured just like ???Redesigning Paris with CityEngine???.
Any more advice on this circumstance?
+++++++ One more question is: how effectively to use some of existing 3D building shapefile (multipatch) and 3D underground drainage lines shapfile (multipatch). In other word, is there any efficient way to integrate those simple 3D models into 3D scene within CE project? If yes, where should those be put so that all working seamlessly in CE?
the standard project structure in the CE is as follows :
assets : 3d objects, facade fotos, the basic elements of your 3d city models [ data going out into the 3d models] data : data such as shape files or FGDB, .. basically street and footprint data [data coming in from GIS] images : any other images, references, ... maps : raster maps such as geoTifs or satellite pictures rules : cga rule files scenes : cej files scripts : python scripts (if needed at all)
- this is just the default and can be changed, but I'd leave it at this. you can create any number of subfolders, if needed. maybe look at the structure of the Philadelphia Example.
- keep file sizes below max 4096x4096 pixels, better 1024x1024 for less important objects. the reason is that the CityEngine processes all these images on the graphics card and not like in ArcGIS, where you only see parts of the data on your screen. Thus, especially satellite pictures should be kept small to work fluently. For high-res visualizations, they still can be swapped for a higher resolution picture at a later time. The CityEngine is a modeling application, not a visualization platform. Please note also that the way the CE works, all textures need to fit in the memory of the graphics card, thus you cannot process GigaBytes of textures.
- the CE uses 2 raster files for a terrain : 1 for the actual height information (e.g. 32 bit geoTIF) and 1 for the satellite picture. Note, both pictures must have the SAME extent ! just play a little with different files.
- I usually use png or jpg files for other textures since they're using less disk space.
- shapeFiles and GDB are supported. any attribute which helps you to define the 3d model is good. E.g. building height, floor height .. a lot is possible !
- as soon as you drop something which is geolocated into the scene, the Scene Coordinate System (SCS) is set to that very projection. Please note that shapes and curve segments can be / are reprojected on import if that data is in a different projection, but raster files are not also reprojected. Thus make sure especially any raster is prepared to match the CityEngine scene's SCS !
* * *
sadly, pipeline networks can not yet be visualized directly from network data (e.g. .stm), but we're working on this.
After initial trial, it looks that majority of those issues are well handled in the release of CE 2011.2, including straightforward setup of any ESRI �??spatial reference�?? and �??geo-referenced data�?? (SHP, GDB, terrain, image) and �??textures�?? in the CE project and also convenient interoperation of 3D scene with ArcGIS 10 SP4 and Google Earth /Google Earth Enterprise.
Personally, the release 2011.2 is improving and making more sense to us!