Understanding Terrain Step

[philip.atha]

I'm trying to understand the meaning of terrain step. Evidently I'm missing the core concept. I'm considering the units system to be meters for my purposes.

If I have terrain source data that's 4096px x 4096px and 1px = 0.854m (real world meters)  Does that therefore mean that my 'step' is 0.854? If not, what then is 'step' exactly?

 

The documentation says:

Step The size of a grid cell in units. Step controls how big the created terrain will be.

 

If I create a terrain using in this context, my terrain appears relatively smaller than where the rest of my objects should be.

[ulf.schroeter]

If I have terrain source data that's 4096px x 4096px and 1px = 0.854m (real world meters)  Does that therefore mean that my 'step' is 0.854?

 

 

Yes. Therefore your terrain total world size (ObjectTerrain bounding box size) should be approx. 3498m x 3498m. You can check the size by selecting your ObjectTerrain instance in Unigine editor (dynamic node info enabed on tools dialog, see screenshot).

 

Radius should then be approx. sqrt( 3498m ^ 2 + 3498m ^ 2 ) = 4947 m. If this is not the case, than there might be another issue (e.g. node scaling).

 

[ulf.schroeter]

@UNIGINE:

 

hm, maybe dumb question, but just by thinking about the above screenshot for ObjectTerrain: the ObjectTerrain centre (= bounding sphere centre ?) is at x=0,y=0 as indicated by the coordinate frame, but the terrain itself only extends in positive x/y direction.

 

Expecting that the depicted radius (= bounding sphere radius ?) encloses the complete terrain, than this bounding sphere would be far too large (inefficient frustum culling) ? Why is the ObjectTerrain bounding sphere centre not at (worldsize x)/2 , (worldsize y)/2 as depicted in the right image ?