tessellation

[crackfox]

is it at all possible to have the tessellation visible in the render as it is in the viewport?

[EvolverInteractive]

Vertex tessellation yes, texture tessellation no.

[ChrisHekman]

is it at all possible to have the tessellation visible in the render as it is in the viewport?

not quite sure what you mean by this. Could you elaborate?

[crackfox]

sorry for not being more specific.

i am playing around with importing some assets which are using native UE shaders with displacement mapping.
this displacement uses tessellation which is not visible in the render but only in viewport.

i was hoping there is a way to use native UE displacement instead of the octane shader, since it would mean i´d need to recreate the shaders for every asset.

[ChrisHekman]

You can enable it by going to Octane (dropdown menu in the unreal toolbar) -> Plugin Settings -> Convert Displacement.

It is a partial conversion for displacement and it dosnt work very well. because UE displacement works in world space and supports more features than octane displacement.
Effectively, it can only do something similar to height mapping in object space. For very simple displacement shaders it can give a similar effect.

[crackfox]

thank you,

if i can atleast use it on the ground level, its ofcourse much better than nothing.

as far as memory consumption goes, is it better to use higher density meshes and instance them, as opposed to using displacement maps for finer detail.

[ChrisHekman]

thank you,

if i can atleast use it on the ground level, its ofcourse much better than nothing.

as far as memory consumption goes, is it better to use higher density meshes and instance them, as opposed to using displacement maps for finer detail.

Unreal dispalcement gets converted with vertex displacement, which will generate a new mesh with more polygons. This means that for octane, it is not a memory optimization.
This means that using multiple instances of the same texture would probebly consume less VRAM

[crackfox]

i think i understand this and can live with it very well.

i was asking this because working with megascans and other ue native assets would be much easier if i didnt have to redo the shaders for octane each time i import something.
so in short, the displacement works but creates more complex meshes and is not memory optimized for octane.

that is fine since on can use the displacement only on the foreground objects if needed.
but can you please clarify: from your other comment i seem to understand that the displacement is height/planar only- or can i use it on uv mapped meshes as usual?

[ChrisHekman]

i think i understand this and can live with it very well.

i was asking this because working with megascans and other ue native assets would be much easier if i didnt have to redo the shaders for octane each time i import something.
so in short, the displacement works but creates more complex meshes and is not memory optimized for octane.

that is fine since on can use the displacement only on the foreground objects if needed.
but can you please clarify: from your other comment i seem to understand that the displacement is height/planar only- or can i use it on uv mapped meshes as usual?

Simply put, in unreal tesselation is done by giving a worldspace vector. This vector contains direction of displacement and magnitude of displacement.
I cant recreate this in octane, as displacement is not done in worldspace, but in object space or tangent space.
Since most displacement used by artists are basically heightmaps, I decided to just take the magnitude and ignore direction as the best possible conversion.

Sidenote: I also found a bug where the subdivision is not correctly set in octane material. The fix will be part of the next build.