Thanks for the update, williams.7489.
I have the feeling the Vertex Maps looked good. For anyone following along, here are some basics.
The Vertexmap is information storage. For every point, a value between 0 and 100%. It was grayed out because (best guess) you were not in Point (Edge or Polygon)mode. If the Use UV Editing Mode is active, it is grayed out as well. If that was a Cineversity tutorial, sorry about that, it should have been stated clearly.
You can set all points at once with the Set Vertex map. When this Vertex Map shows up as a Tag in the Object Manager, then you can select it and (POINT MODE) paint on it to refine it.
Besides, in your case, click on the Vertex map and then check the box Use Fields. The fields will set those point values. For example, a Linear Field is like a gradient. Wherever the gradient is, it has a certain value at the position a single point is, that value will be given to the Vertex Tag. All points that are affected by this Field will be determined in value by this Field. However, if the Points are deformed, you need to use the Deformed Points checkbox to progress.
Inside the Field List, you will get options to combine those Fields. Standard comment here: It is like Photoshop Layers. Kind of.
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Any critique should be given in a way that you tell what you want, and the other side tells you what works and what doesn’t. We all get lost from time to time, nothing wrong with that. This should ALWAYS be done in a motivational manner, with tips and examples. Anything else is just a failure on the education side.
Anyway, please focus on what you like to do. You have been staying in communication, and you keep going. That is already half the “battle”. Always keep in mind, there are no failures, only gained experience. And that should be the permanent mantra from everyone. You keep going – that is what not everyone can do.
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So, as I mentioned, we like to split things into workable units. So we can work on one part, and when this works, we do the next. If we like to do it all at once, like the texture covering the grass and the changing V shaped formations, you are not splitting things up.
I have used the mesh, here the polygons to split the texture. There is a top layer (the green [yellow] material applied as UV, and the Gradient, which is applied as Flat with a 45º rotation to get the most sides of the rivers detailed. The most right-sided material would be on the top. So I used the Polygon selection to limit its area to the top. The sides start with the same green tone and move then into soil colors.
Please have a look here.
Another option would be to texture the model in the two versions. The first one from frame 0 to the point the channel is established. The second starts just before the channel grows and then to the last frame. Since you said you are familiar with Ae, you place these two renderings on top of each other and draw a mask (animated where both overlap). This mask unveils quickly the changes. So, you could really paint your two version on a texture and use each for one of the clips.
Let me know if there is any further question. I’m happy to look into it.
Cheers.
P.S. AEC, it should work if it is placed here, I checked it with the latest Ae.