A quick question regarding exporting a small piece of foreground terrain

[virgil_182]

I have been working the last few days on conceptualizing and designing a possible pipeline integration and work flow for for use of Terragen 2 as the sole environment and outdoor set renderer for an animated short film.

Nagging UI issues aside, I've been largely successful and it appears it will work.

One of the things I haven't been able to figure out, however, is how to export, say, a 20 foot by 20 foot section of the foreground terrain immediately in front of the camera as a map that can be used as a displacement to recreate the small slice of terrain to be used as a shadow catcher for compositing characters and complex animated objects rendered in another app. I do not have immediate access to an animation capable version of Terragen, but I do not believe it is capable of handling complex skinned and animated characters or deformations so I assume I will have to comp shadow interactions from another app.

I've included one of my quick tests to illustrate. Imagine an animated character running into frame. It would be nice (not absolutely necessary we realize, but nice, if the shadows would interact with the actual displaced terrain in the render.)

The sphere is there just to test lighting and shadows, it's not supposed to be pretty. hehe

Do any users here have experience compositing TG renders into scenes that require fairly small scale interaction like the shadows issue I mentioned ? Any tips would be appreciated. I haven't yet tried wrapping my head around comped character interaction with populations, but we'll probably just do a similar approach, using a small section of scattered sagebrush in the primary renderer then comp. Which brings another question, is it possible to create a traveling map that would suppress the population render in the same small foreground area as the camera moves through the scene ?

While I'm on the subject a million other questions pop up but I'll keep it relatively short.

Any advice from those with experience in compositing Terragen renders would be greatly appreciated.


Thanks for your time.

[Oshyan]

This is actually fairly straightforward. You will want to create a new Heightfield Generate, then plug your terrain network into its Shader input. Set the "Size in meters" to the size of the area you want to cover, set the resolution just above that to the maximum you will need (it's measured in pixels), then position it in the location you want to export (you should see it shown in the 3D preview as a white rectangle). Now just hit Generate and it should create a heightfield. Right-click the Heightfield Generate node in the node network and choose Save As, and you can specify TIFT as an output format (add the file extension to the file name). This will give you a displacement map. You can also export to LWO geometry by using the above steps and then feeding the Heightfield Shader into a Heightfield to LWO node.

- Oshyan

[virgil_182]

Oshyan, Thank you for the prompt reply, I will be experimenting with it more this week.

Edit: Originally I had another question concerning Ambient Occlusion surface shaders for objects in TG2, but some more experimentation reveals that with clever ground cover placement, or a few easy workarounds the hard "3D" edges between objects and the terrain shaders are easily hidden, or minimized. (I am using a modified version of your fake GI lighting rig so AO at object / terrain intersections doesn't work well. )  Of course, assuming the terrain patch export works, AO will be a moot point, because the foreground objects will be rendered in another app.

Thanks again for your time.