Unity 5.4.1f1 Personal Lower Terrain Not Working

I'm new to Unity and working through a tutorial in the book "Getting Started with Unity 5". The tutorial starts with creating a terrain object, resizing it via the Inspector, flattening it. Next I am to use the Raise/Lower Terrain to add mountains along all four sides. Then it instructs to add a river through the middle by holding shift+click. I was able to complete all except the river instruction. The mountains show in the Scene view as expected. However I don't see the river where I drew it. I've Googled and searched this forum to find an answer and found none. Please tell me why I don't see the river, and how do I fix it? I am running Unity on a HP laptop under Windows 10, 8GB RAM and saving my file to my external drive where I have saved other tutorial projects for other software.

 

Did you read the Terrain doc? https://docs.unity3d.com/Manual/terrain-UsingTerrains.html

I'd recommend reading it, as just following tutorials isn't going to teach you how it works. Trust me, I've been there.

To lower terrain, you need to select the farthest left selection tool (as shown in the doc). However, you can NOT lower terrain that is at the original height. You first need to add height, only then can you lower terrain.

 

DroidifyDevs.
Thanks for your response. I read through the manual and the tutorial I working on said the same thing. Here are screenshots which match those in the tutorial.


The river is suppose to be running left to right through the middle. According to what I read in the manual and the tutorial there should be a depression there but it's not. What did I not understand or do?

 

The middle of your terrain is flat. Because it's flat, it can't be sculpted down (don't ask me why).


https://docs.unity3d.com/Manual/terrain-Height.html

So unfortunately when you raise your terrain (as shown in the picture, select a decent height then press flatten), you'll lose your work. You've already run into one of many limitations of Unity's terrain, which is why many people use different terrain makers.