I've started using the new sop_terrain_segment_rop node along with the new terrain texture rop also provided with the game development toolset dev update and I noticed an issue with the exported meshes. I've created a shader in an external engine with standard RGBA 4 layer terrain technique with a macro normal and macro splat. The Macro Normal seems to be flipping a few vertex normals on the exported Houdini mesh. It's odd because the mesh looks totally fine when viewed in maya with vertex normal custom polygon display turned on, all normal are facing the same direction, etc. So I'm not really sure what's going on. I've checked my shader on various other meshes created in Maya and they seem to work fine…

Anyway, I am curious if anyone reading, and definitely a SideFX person, could whip up a similar shader to see if they exhibit similar artifacts from their Macro Normals.

Is this a unique problem to what I'm doing or is this something other people are experiencing?

This might be a silly question, since I don't know much about your setup: Is it just some of the normals that are flipped, or are they all flipped?

Houdini's normals are left-handed relative to the winding order, so they're the opposite of almost every other tool out there, unfortunately. If the mesh is composed of polygon primitives, you can try applying a Reverse SOP to it to reverse the winding order of all of the polygons.

Its just some of the vertexes and not the whole sheet, which is weird, its usually an all or nothing kind of thing. I haven't experienced something like this before. It also comes in kind of a pattern…like 3 vertexes in a row look flipped, then 2 would be fine, the 1 vertex flipped, then repeats all along the edge loop. And theres maybe 5 or 6 edge loops like this across the terrain chunk.

update: good to go, not sure what I did yet exactly, but I fixed my issue!