Can I import OBJ and use it as base mesh?

[panupat]

Hi everyone. Very new to Terragen and I have a question about workflow.

Usually the layout guy will give me a block mesh, which I then send to zbrush to block out further shapes/detail. Now, would it be possible to send this into Terragen as OBJ and use it as base terrain? Ideally I only want to apply addition effects on it without changing it's height or overall shape too much. If this is possible, how do I do so?

So right now, when I import OBJ, terragen would ask if it's an xfrog. I say no, and I get a new node for my object in the node editor. But seems unable to connect to anything.

Thanks.

[cyphyr]

Hi and welcome to the forum

The short answer is "no". There's a number of things to bear in mind however.

You can import a "base mesh" and texture it with Terragen's procedural shaders, however displacement options will be severely limited and you can not place populations on them (for example you could import a model similar to say the arches in Avatar you could not place a populations of trees/shrubs/grasses on them).

You can displace a mesh if "Ray Trace Objects" is un-ticked (in the render tab), however any shadows cast by the object will be from the undisplaced mesh and you will probably need a high density mesh for the relatively larger displacements. Also you'll have to be careful to avoid exploding polygons. Displacements applied when RTO is enabled will work in a similar manner to a bump map. Nothing will actually be displaced but the shading will be as if it were.

When you import a mesh it will not need to be part of any of the existing node trees so it dose not need to be plugged in anywhere, to move it about you can either directly drag it to where you want or use the numeric "Translate"  input in the node interface. You can also right click on the terrain where you want the object to be, select "copy coordinates" and then paste those coordinates in to the numeric input (small copy/paste icon to the right of the "Translate" numeric fields).

Hope this helps

Richard

[panupat]

Thanks Richard. I'll see what I can do. I still couldn't find a way to apply procedural filters on my own mesh tho. If I have time this week I'll definitely sit down and learn all the basic.

I'm ok with height. Because I can't change the form of my object much But I'm really wanting to apply erosion and all other cool stuff Terragen can do. LEt's see how it goes 

[cyphyr]

If you want to apply erosion through the general procedural filters the it's "possible" although an interesting challenge, however if you plan on using the "height field opperators", they wont have any effect on a base mesh. (don't think they will even plug in!)

If your base mesh has NO overhangs you may fine it more productive to turn it into a gray scale bitmap and import that as either "Heightfield Load File" or as an image map set to "plan y"and displaced. You could then use all the "height field opperators" and add populations as desired.

Richard

[Oshyan]

Objects are treated fundamentally differently from terrain at this time. Objects are, in general, more limited. You cannot populate other objects on them, as Richard noted; you cannot apply significant displacement to them in general, except for very dense messages they tend to "explode" or fragment, which I believe is due to lack of subdivision in the object rendering process; finally, you cannot apply Heightfield operators to objects, e.g. erosion. You can however use normal procedural texturing, which could give the impression of erosion; but to be clear, it is not a simulated erosion process.

- Oshyan

[panupat]

Ah I see. Thanks for your response I guess I'll have to try play around with the actual terrain then. Might be able to get it into Zbrush to transfer interesting stuff over other models that way.

Thanks!

[Oshyan]

One possible option would be to export a Zbrush displacement map, apply that to a terrain using a Displacement Shader, then perform operations on that. You could export as geometry with the Micropoly exporter.

- Oshyan