need to create a 3D map with elevation point in meter coming from google dem api

[Edwin]

Hi,

i need to create a 3D image with the elevation data provided by google in meters unit. I don’t want to use heightmap image. I need to create it with the xyz coordinates. The elevation value coming from the dem api are in meters. I don’t know how to calculate the x and z corresponding to this elevation value in meters.Please help me with some examples.

[Wingnut]

Hi, welcome to the forum.  Those structures are called "heightMap" and "displacementMap" in BabylonJS.  Sometimes two words... "height map".

You can do a forum search, docs search or playground search... for those terms.

The basic playground demo for height maps... is at:  https://playground.babylonjs.com/#95PXRY#0

Importing tiff files... I don't know about that, sorry.  Stay tuned for more comments.

Also, feel free to edit the TOO LONG title/subject field...  for your first post.  (thx).

[Edwin]

Thanks wingnut, actually I don’t want to create it with the heightmap image. I want to create it with xyz geographic coordinates. Now I am confused about to create x and z value corresponding to the elevation values that are in meters. The elevation points I am getting from the Geotiff file. I am reading that Geotiff file with Geotiff.js library.

[Calsa]

I just was looking into this myself a few months ago, though I was pulling from offline open source ASTER Sat Images as Google  / Bing API Costs $ and as I am working in a fairly remote part of Madagascar right now internet is not reliable (often not existent), so in my case everything has to be designed to work offline :x

Hope this helps:

Andy Beaulieu had a nice tutorial with code to pull from Bing API: http://www.spritehand.com/2013/12/bing-3d-maps-using-webgl-and-babylonjs.html

The Google API is obviously are not identical but under the hood they have similar functionality / way of doing things. It should give you some ideas if nothing else.

The Dynamic Terrain Plugin is a good place to start for creating terrain tiles from height maps, using the metadata in the GeoTIFF you can set vertical Scale  & AGL of each tile so they line up : Dynamic Terrain: https://doc.babylonjs.com/extensions/dynamic_terrain

Just a cool demo from Dotvision: http://live2.dotvision.com/live/virtualTour?guid=f0045a3c-6c11-4329-b881-8d8a170538fb&lang=fr&intro=true

Happy Coding!

[Edwin]

Hi Calsa,

Thanks for the help. I have tried all these above but didn't get anything. Actually i am not able to calculate x,y and z coordinates. my elevation point is coming in meters(unit). from the geotiff file i get the rasterData with the size of width * height. now i am confused how to project it with x and y so that i can get the correct elevation on texture image.

 

[Edwin]

Hi I am trying to do this like the below.

https://www.babylonjs-playground.com/#FJNR5#269

can you please help me to get elevation data calculated correctly without using noise library ?

Thanks

[Sebavan]

The elevation scale needs to be calculated from the data you exported from the api.

Let s say you export a 2 * 2 m area, it means that x and z would be between between 0 and 2 so you need to remap them from 0 - 90 to 0 - 2:  https://www.babylonjs-playground.com/#FJNR5#287 As the elevation is in meter it does not need to change.

That said it is still strange to have lots of 0 in those data creating weird discontinuities everywhere.