Landscape: Add image overlay on top of terrain using real heightmap data

I have found various methods/software for importing real world height data to form the terrain. However, I am unsure how to then add an image overlay to the terrain using e.g. google earth or maps to get an exact layout that acts as a guide for painting the terrain thereafter.

Any and all advice is welcomed. If it is the docs and i have overlooked it i apologise, and would appreciate a link to where it gives such info.

Answer:
Create a special landscape material, set the base material as a texture that you can swap out (parameter) in your instances. as you paint the landscape you “Fill” layer 0. (you have to get the right scale for the UVs using landscape layer coords. shouldn’t be too hard since the size will be precise)
Then you can overlay the other layers as you normally would.
and eventually remove the 0 layer from the material.

The real way:
I would suggest you learn how to use Qgis - it’s free.
It lets you manage your DTM and pull satellite imagery.

It’s complicated. it will take time.

Qgis will allow you to keep the data of the tile and satellite in relation.
It works with Geo Referencing, Extents, and Columns instead of pixels.

Given this. the program will let you color and export your digital terrain model in different ways based on height data. as well as give you a 1:1 relation between what you export and the satellite image.
Meaning, you can export the satellite image, and create a manual “splat” map to use during tile import.

I would like to share the way I did this. I am modeling some realistic terrain with lakes and wanted to use the NOAA depth charts to match the depths on my landscape. For context, I have my landscape and then a plane that is the water/waves.

Here’s my process:

  1. Download the image you want to use.
  2. Import into your content (wherever you want to store it, doesn’t matter)
  3. Create a new material with an easy to remember name (e.g. M_Lake_Depth_LakeName)
  4. In the material, add a Texture Sample node and use the image for the texture.
  5. Connect the RGBA output to the Base Color input.
  6. (Optional) Add a parameter to change the Opacity.
  7. In your scene, create a basic Plane object.
  8. Set the texture of the Plane to your new texture.
  9. Scale the plane to match your terrain.
  10. Show/Hide layers as needed or change the Z height of the plane to intersect the landscape. You could also raise the plane above everything and change its opacity.

Hopefully this helps others with an extremely simple way to use reference images!

Is there to do this also for tiled landscape? I have a landscape with 4x4 tiles. I have the DEM and satellite image overlay exported as tiles with common names. While importing the tiled landscape one could provide tiled masks but not tiled textures. Am I missing something on this?

I read somewhere that for this a material instance need to be created for each tile and merged into the mastermaterial.

See this original post link text

But I dont quite understand how to do that. Any hints would be most welcome.