So I have got myself quite confused with the coordinate system and up to now have muddled through, but I really need to resolve an understanding. In the case of a landscape, what in the hell are the transform coordinates relative to?
I read somewhere that all objects with position are relative to a parent, but does a landscape have a parent or at least does it have a parent itself with co-ords.
If you look at the basic setup of a new project, with third person character and starter content, all the walls, walkway components, floor and third person character all seem to have a different z-axis. I get that these are all relative to something - but what? Or maybe at what point of reference, are some objects based on centre of gravity rather than beneath the feet?
My motive to come back to this issue was that I had been having some problem with tiled landscape levels and understanding the z-axis (frankly the other axis have left me with the similar questions) but I thought that I would gain clarity by bringing in a single tile as a landscape component into this basic setup, and looking at the relationship between the elements. When I imported the tile (heightmap) it defaulted I think to 0 on the z-axis but it appered to be conceptually hundreds of feet below. I zeroed all elements on the z-axis and still it was apparently hundreds of feet below. Also I notice that if I change any item from relative to absolute location type the values do not change - as if both world origin and local reference are always one and the same thing, seemingly they are exectly the same offset from something. What am I not gettting?
I’ll ask what might well be a dumb question here…
Have you seen the switch here to toggle between world and local mode?
It’s just that if you hadn’t ( I didn’t for a long time ), you could easily wonder why all the gimzos are pointing in different directions.
Z is always up, in the world…
Yes thanks for coming back to me on this #ClockworkOcean, yes I had seen this but the results didnt seem any different from where I was. I have just double checked however, if from my camera position I raise one of the wall segments by visually its own height (as lined up on the adjacent wall) it goes to Z:800 and that is the same for both world and local space, I tried a similar experiment along the x-axis and again exactly the same change on both methods. And like you I have to confess I was along time realising what that button was supposed to do, but then maybe it wasnt doing what it was supposed to!
Ok, my bad. Are you talking about these values?
The big wall and small wall have different Z. This is the height of the pivot point from Z=0 ( the ground ).
( Sorry if I’m still missing the point )
Well yes and no. If you look at the scene objects like the wall and the cube (capture1 perspective=Left), they have cordinates that are based on what I was calling centre of gravity rather than pivot point(nube’s lack of 3d or unreal terminology).
And if I raise the CubeMesh to z=500, it behaves predicatably and the value is the same whether using world or relative coordinates. Presumably the World Origin (red centre line) then is the CubeMesh parent.
But the Landscape (capture2 perspective=Left) is also with z=0, yet far below the other items, and if I change its value to 20000, it is still far below, though of course at a smaller offset.
So what is the Landscape’s z-axis relative to? What is its parent? Have I misunderstood the world origin?
And whilst not really about the subject question of Ladscape cordinates directly, but part and parcel of the same coodinates understanding, how do I line up objects on floors precisely if as in the case of the CubeMesh there does not seem to be a height value only a pivot point?
I put a 7x7 landscape in the default level, and got this:
The pivot is on the corner, but it’s only 100 above zero. Something strange seems to be going on with your setup maybe?
OK so I see that if I create a new tile it does act in an expected way however when I import a tile, the sample used is a 1009 x 1009 imported at prior location spec xyz=0x0x0. Its subsequent transform shows xyz= -5040 x -5040 x 0 The scale if it has a bearing is the default 100x100x100. The fog is still hanging heavy!
So the fog is still hanging heavy! Can anybody else help with this?
I am confused about the coordinates for imported heightmap based landscapes. What are landscape tranforms relative to in the case of local coordinates? And in the case or world space coordinates why is z=0 after import when it is way off the world origin?
That does sound like an import problem. Maybe post again, and just focus on the transform of an imported landscape.
I couldn’t find anything useful ( because Epic have trashed a lot of search look ups ), but I don’t know if this is of any use:
Thanks for that ClockworkOcean - I have seen a lot of videos about how to inport tiles etc. This particular guy is a little bit dubious on some of his assertions and certainly his recokoning on what makes realistic height scale is laughable! Anyway it was worth a watch.
So the fog is still hanging heavy, but thanks anyway.
In fact without even importing a heightmap (perhaps this was a red herring) if I create a new landscape, specifying position 0 x 0 x 0 after pressing create it is located at -5040 x -5040 x 0 -
Why has it got this offset?
Becahse the landscape is 5040*2 wide.
