During the production of Initen, I was given the opportunity to develop our own terrain tool to fasten our workflow. I took inspiration from Abzu, in which they created a mesh based terrain tool, that allowed them to create terrain directly from shapes.
The tool will automatically look for any terrain in the scene, and you will be able to bake all the desired shapes in the terrain, which will take the resolution you desire. The tool is able to handle multiple terrain at once, and you can override the general properties for each one.
In addition to that, I added a normal blend shader that behave exactly like a normal shader, except it allow meshes to blend with the ground, with a pattern or just a gradient.
So far the tool is working well, but it still needs some feature before being released :
-Needs to automatically create different materials for the different objects blended with the terrain.
-The terrain needs a custom shader which would allow it to react to the object, to help the blend with the rocks and so on.
-GPU Instancing is currently working with the terrain tool blend shader, but it would need a better setup to allow variation in the way meshes blend with the ground.