View Full Version : Sculpting Terrain

06 June 2005, 01:49 AM
I have a Vue scene where the objects and camera have exact placements and cannot be moved. I drop in a terrain object and then want to modify or "sculpt" the terrain around the main objects. For instance I want to place a stream (a gouge in the terrain) in the foreground right in front of a bridge.

My question then is how a person who is comfortable with Vue would sculpt the terrain to fit his scene.

When using the terrain editor, I find it easy to do major modifications to the terrain (canyons, lakes, erosion, etc), but find it very difficult to take specific changes. For instance, I want to reduce the height on a specific hill or peak so that it does not obscure an object behind it. This seems to require switching back and forth between terrain editor and render camera - a very imprecise process at best. It usually takes numerous passes and rarely achieves the result I was hoping for.

My thought at the moment is to export the terrain to Maya where it can be sculpted because the scenes in Maya and Vue are sychronized. Then export back to Vue. However, I believe I will no longer be able to treat the imported terrain as a terrain and loose the ability to use the terrain editor.

Sorry for the lame question - just wondering if there is a better way.

06 June 2005, 09:07 AM
Not at all lame - it's a very good question and sometimes it bugs me, too. I'm currently working on something that requires a rather precise landscape topology and I use a bitmap as basis for the terrain. The vector drawing or blur tools in a 2D paint program can create smooth gradients and you can always convert the terrain into a procedural model. It would be nice if it was possible to adjust the terrain in the 3D views, but...oh well, maybe next version. Anyway, that's how I do it at the moment.

06 June 2005, 11:48 AM
This won't help you now, since you said you have exact camera placement, but when I start a scene, I move the camera to the middle of the bottom of the window, facing 'north'. This way I know exactly what the camera is looking at when I open the terrain editor because that is the way the terrain is oriented. It is still difficult to make minor adjustments and small tweaks (I'm hoping in future releases, this will happen), but it does help.

06 June 2005, 11:19 PM
Both are good suggestions. Using say a greyscale photoshop cloud texture creates a more pleasing terrain than anything I've been able to make in the terrain editor. As for orientation, I applied a checkered grid material to the terrain using different color checkers in each quadrant, and then compared that with the topview in the terrain editor - useful for getting oriented.

I would love to see a material overlay in the terrain editor, an overlay that could temporarily replace the alttitude elevation color maps. I would also love to see real time changes in the terrain editor reflected in the 3d scene. But I digress...

I created a photoshop bitmap and used it to create a bitmapped terrain in Vue. Exported the terrain using a 4k vertex count to a Wavefront obj/mtl file for import into Maya. Once in Maya, the imported terrain was "smoothed" or subdivided by a factor of 1, and then small patches of the mesh were refined in the foreground which allowed for detailed sculpting using the polygon sculpting tool. Same tool was used to etch out a river and a walking trail.

After deleting history, the terrain was exported from Maya in obj/mtl format (about the only real choice with Maya to Vue). When I went to Vue to import the modified terrain now with about 44K vertices caused Vue to go off to never-never land (100% CPU utilization) and never finish importing the terrain. Getting control back over my workstation takes about 20 minutes since the system becomes very unresponsive. Oh-well, I'm going to open up another thread on this issue.

This of course is a major disappointment because I would like the terrain back in Vue for texturing, but for the moment I will simply texture the original Vue terrain and export the bitmaps to Maya.

My desire was to render in Vue, but at this point I don't think I can do that. However, I can continue to use Vue to generate good looking rocks, water, plants, etc for export to Maya. Let's see if any of you good folks can rescue me from this predicament.

Comments welcomed and many thanks for the help - keep it coming.

06 June 2005, 12:13 PM
Hmm. I know nothing about Maya, but couldn't you somehow render the landscape into a hi-res grayscale bitmap and create a new terrain based on that? Of course, it's a clumsy solution and may lose detail, but..

By the way, if you click the preview window with the terrain editor still open, it will force an update of the terrain in the scene - the editor will remain open so you can undo your changes. You can even do a full (window) render this way.

06 June 2005, 09:03 PM
By the way, if you click the preview window with the terrain editor still open, it will force an update of the terrain in the scene - the editor will remain open so you can undo your changes. You can even do a full (window) render this way.

Good tip - clicking the camera preview window while in the Terrain editor does refresh the terrain in the scene window. Fantastic!

As for using bitmaps back and forth between Vue and Maya, its been on my mind to investigate this. Using high resolution bitmaps would work, at least in theory. However, the mechanics of going from Maya to Vue using bitmaps is not clear to me although I suspect its not that hard. I'll post here if I learn anything. Thanks.

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06 June 2005, 09:03 PM
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