it said "invalid position" just like object overlaping, but theres are nothing

In the Large Area maps, you will always get this error along the inside and outside edges of the pavements and in the middle of the roads (on the white lines).
It's like the whole map is made in tiles, and where the 'tiles' meet (pavement edges, road crowns) there's a space that doesn't accept objects that run parallel with the join.
You just have to offset by a small amount.

But why is that? Is it a bug or a limitation of the layout system?

If someone could provide a very simple way to reproduce this (hopefully with a single object) then I could have a look to see if the same bug still exists in new LFS.

I have a very simple way to reproduce this, as this happens in many locations in Layout Square, typically along the seams of all road components (the road itself, cobblestones, etc.); there are actually several thousands of such invalid locations.

I'll edit this post in a few minutes with some examples and ranges of coordinates. Note that, of course, placing objects at those invalid locations, but "floating" does work (but you have to place them slightly off before as "floating" is off when placing objects).

Edit with some examples:
Any point at X=-4.75 and Y above -980 and up to -20 inclusive.
Any point at X=-4.75 and Y above 20 and up to 500 inclusive (this one is only invalid halfway along the road).
Same Y coordinates but X=+/-8.00, +/-6.75, +/-6.5, +/-4.5, +/-2.25, 0.00.
The same occurs along all 4 roads around the (0, 0) point, and probably on most roads.

If you place lines at the points on my image, then try to move any of them right, then you'll get the invalid position error.



Although I've marked a position for the yellow line, you'll find it happens on any part of the road anywhere on the map.

Thanks, I reproduced this and it does also occur in the new version.

I'll make a note to consider it but I guess not with high priority.

Does anyone know if wheels sometimes drop underground at these locations?

No problems with wheels, nor with placing concrete objects.

But happens with every other object, such as lines, cones, tyres, armco, barriers, markers, checkpoints, etc.

I've never had an issue with wheels there either, but your question reminds me of something (this is regarding tyre physics, sorry for derailing a bit): I assume this is related to raycasting possibly finding a gap between the physical objects, which could cause a wheel to sink into the ground (as happens in some other places, or sometimes between 2 concrete objects) - is the future tyre physics (not the retro model for the coming update) also based on what seems to be a single raycast, despite the contact patch simulation?

It would be really nice to see an improvement in this area, and maybe allowing for a secondary contact patch (for wheel to wheel contact for instance, or hopefully better kerb physics, as right now, the wheel will jump up or down a kerb (or tramway rail in SO) with no impact on the car's speed. The one situation where the contact patch shifts is with the speed humps, but you can see the contact patch jump instantly from vertical to ~30 degrees). Hopefully this is something that can become possible down the road, with the multithreading helping performance.

Quote from Scawen :

Thanks, I reproduced this and it does also occur in the new version.

I'll make a note to consider it but I guess not with high priority.

Does anyone know if wheels sometimes drop underground at these locations?

Chiming in - yes I have had same issue but nothing so debilitating that it affected overall layout quality. Haven't yet had to drastically amend corner geometry or track width to accomodate as such, so yes indeed as you mention it shouldn't be top priority ; many other more impactful stuff you guys have planned for that we're sitting rubbing our hands waiting with crossed fingers!