Hi Ida,
Everything that is happening in this video seems to be working as expected :
- In the initial section of the video [0-10s], you are affecting the first edit layer in the stack (“Layer”), and the current height of the spline is written into it (note that since you’re not using the Splines edit layer, you are not using a non-destructive workflow and therefore, the spline data is written on top of the existing data, which is why, when you move the spline around, the terrain is still deformed to where the spline was previously located (instead of only around the spline, as you would get if you had used a proper Splines Edit Layer)
- Later on in the video [10 - 25s], you are affecting another edit layer (“MyLayer”), but that layer is also a standard edit layer, and unlike the Splines Edit Layer, those blend additively. Therefore, the height coming from the other edit layer (“Layer”) is added on top of the one written into “MyLayer”. So technically, the “Editor Apply Spline” did its job and rasterized the spline into “MyLayer”, but since you have some height data on the other layer, the final height ends up higher than what you would expect. You would need to erase the height from the previous layer(s) in order to get “MyLayer”'s height to be the one from the spline.
This is why the Splines Edit Layer comes in handy : it ensures that all splines data is written into 1 and only 1 layer and it does so in a non-destructive way (i.e. every time a spline is adjusted, the previous spline data is “erased”, so that you effectively always have a height that matches the current location of the splines), but also, it has a different blending policy than standard edit layers, that is akin to alpha blending : at the location of the spline, the final height will be the spline layer’s height, no matter the height on any of the layers underneath (alpha = 1). Then, as the distance from the spline increases, alpha decreases, and we blend the spline layer’s height towards the accumulated height from the edit layers underneath. Splines can even have a settings to only allow raising the terrain from previous layers, only lowering it, or both.
This method you are using to write height from splines comes from a time where edit layers had not been implemented and it isn’t used much anymore, since Splines Edit Layer is much more user-friendly. If possible I’d advise you to use it. The one caveat is that you can only have 1 Splines Edit Layer in your landscape and therefore all landscape splines will write to the same layer. In practice, we’ve never received complaints that this was a problem, though.
I hope this helps. Let me know if you have any question.
Cheers,
Jonathan