You don’t. You apply the blended output. There’s no need to continuously reblend everything. Once it’s in the RVT, you just sample from it directly.
So in your case, you have a node “Landscape Layer Blend”. Connect it to a “GetMaterialAttributes” node and add the attributes you use. In my project, I’m using BaseColor, Specular, Roughness, Normal, Displacement and Opacity Mask. Your RVT texture needs to be set up to support all that. It’s the “Virtual texture content” field on your RVT.
From the get node, there’s a material pin you can pass through to your Landscape material output. And individual pins you can use to write to the Runtime Virtual Texture Output node.
This sets up the ability to write to the RVT texture.
Right, so everything we’ve described above is for the “No” pin of the Virtual Texture Feature Switch" node. And on the yes side, you just sample from the RVT.
Probably better to give you an example. I’ll only show the part you’re missing since I do some weird stuff with height maps.
So everything you have would be at the top of my screenshot up to the LandscapeLayerBlend and writing to the RVT Output. For the RVT sampling, you can use either RVT Sample or RVT Sample Param. The Param one lets you create Material instances that use a different RVT. Useful if you have multiple levels.
If it has a VT symbol in the texture preview, you CANNOT use it in a landscape material. You WILL get blurry textures. If you say that when you enable virtual textures in the project settings, they instantly show VT, I think they are already VT to begin with and when you turn off virtual texture in the project settings, it just can’t use that feature anymore and treats it like a regular texture.
So you need to convert those texture you use for your landscape to regular textures. You just right click on it and select “convert VT to regular texture”.
It’s also possible you have “Enable virtual texture on texture import” checked in your project settings. This could explain why everything is a virtual texture.
Another important setting is “Auto Virtual Texturing Size”. If this is a small value, then everything you import will turn into a virtual texture even when the setting in the previous paragraph is off.
Once you convert your textures, your material will likely complain that the sampling type is incompatible. You’ll need to change the sampling types to not be virtual. Instead of Virtual Color, just use Color.
This is just eyeballing it. You have several properties on the landscape you can adjust. They are located under the “LOD Distribution” section of your landscape actor. You will have “LOD 0 Screen Size”, “LOD 0” and “Other LODs”. These tend to depend on how you use your UVs. So I can’t really go over this. But it’s not too difficult to see their effects.
The red line is in the view itself as an overlay when you type “r.VT.Residency.Show 1” in the console. Then you’ll get something like this:
The red lines in the graphs show the pool usage. Note that most of this will not come from your landscape. It will come from your other assets in the world. Why does this affect your landscape? Because there is limited resources. If other assets take up too much memory, then everything will start to use lower LODs, including your landscape, in order to save memory and keep your game running.
Hope this helps.