How do I move terrain along Y

[himalofa]

I'm sure this must be really simple. I just want to lift or lower a terrain, ie move it along the y axis. Using the arrows I can move it in X and Z but despite the Y (green) arrow looking active it refuses to budge.

[jritchie777]

I'm sure someone will correct me if I'm wrong, but I had problems with this too.  For Terragen 2 (T2 as I like to call it), the Y axis is the vertical or up and down - which you probably already know.  Unfortunately the only way I found to effect the height is to enter it into the Feature scale; however this just makes the terrain higher or lower if a negative value is used and does not actually raise the terrain.

I've been able to use a plane object and a crater shader with it using a negative value I can make a spire and use the plane to elevate it off the ground.  Have not been able to do it with a heightfield though - some one smarter may be able to explain that.  One big problem with planes though, you can not select and/or move them in the preview window - it is all done with coordinates.  One other thing to be careful of which I found out the hard way (hours of experimentation) you need to have the same coordinates on the shader as the plane.  For example, the crater shader I used needed to have the same center coordinates as the plane to actually be on the plane.

JR

[himalofa]

Thanks for the quick reply but I just want to lift a heightfield and not add any extra geometry.

[Henry Blewer]

There is an operator available for heightfields. It's called the heightfield adjust verticle and can be accessed by selecting it from the operators selector. Make sure the heightfield is selected or you will get an error 'Please Select a Heightfield'.

[jritchie777]

I've tried that also, but it doesn't seem to raise the heightfield off of the ground plane.  How does it hook in to the heightfield in the node network?

JR

[Oshyan]

The Heightfield Adjust Vertical will raise the height of the heightfield, but it will still be attached to the planet - it will not "float". I'm not sure what effect you're after, but if you want a floating terrain, not attached to the planet, then the heightfield will not currently allow you to do this. However you could try a displacement on a plane instead. If your heightfield is internally generated in TG2 right now, generate it then right-click on the heightfield generate shader and choose Save As, save as a TER, then use Terraconv to convert to TIFF. Now create a plane, go to the Default Shader it comes with and to the Displacement tab then load your TIF file as displacement and adjust until you see the right terrain shape.

- Oshyan

[himalofa]

Oshyan, I will give that a go, although it seems a bit complex just to nudge a terrain vertically. My main reason is in following others ideas in making rivers using a second copy of the terrain as a lake object. In order to preserve the slopes and size of the lake terrain it just needs to be lowered a bit and not altered in size in any way.

A secondary reason that I have not explored yet is for georeferencing where the altitude is critical.

[Oshyan]

The technique I described is completely unnecessary if all you want to do is have a second terrain for water. I described it specifically in reference to if you wanted to have a "floating" terrain, like a sci-fi shot for example.

If you're using a heightfield terrain, just select it in the node list on the left and then click the Add Operator button and select Heightfield Adjust Vertical. Adjust settings to the needs of your scene. That should do what you need.

- Oshyan

[himalofa]

Oshyan

If I use heightfield adjust the terrain seems to be decreased in height relative to zero altitude thus altering the slope. This means the edges of the terrain are lowered far less than the center making the rivers overflow their banks toward the terrain edges. I am using GC2 to dig out the rivers using dry for one terrain and filled to about 80% for the water terrain.

I could not get your displaced plane idea to work either. When I applied the tif as a displacement the plane vanished.

[Oshyan]

Try using Add Height in the Heightfield Adjust, not the Multiply Height.

For the Plane approach (again *only* necessary if you are trying to get a "floating" terrain), I realized it would actually be a little difficult to use the Default Shader by itself because it doesn't allow full control over your Image Map. Replace it with an Image Map Shader and you can then set the size of the terrain equal to the size of the plane (make sure the plane is large - it starts out with default size of 1x1 meters), as well as changing projection to PlanY. That should make it work. I can provide an example TGD if you need.

- Oshyan

[himalofa]

Add height does the same thing, there is still no alteration of height at the edges of the terrain.

[himalofa]

Just done some more testing with add height and although the edges are not altered it is only the fringe of the terrain that does not alter height. I can live with this. Sorry to be such a pain but this is a tough learn for me, especially with very little documentation. This forum is a life saver.

Thanks.

[Oshyan]

It sounds like you're having trouble with the border blending. Just set it to 0.

- Oshyan

[Dune]

I did some experimenting with this. My posts (about rivers) should be around somewhere. In short, I connected the original heightfield to a lake object (temporarily exchange the water shader for a purple surface shader), and played with the height. To slightly 'even' the terrain, put another compute terrain between them and set the patch size to 40 or 60, or check smooth terrain. Now if you carve your river into the original, after the line to the lake(!), the lake should be visible in the carved out river. With a little more experimenting maybe that's what you're after?

---Dune