Modeling out a trench system?

Jubbie112

So I've been looking to create my first real piece of environment, the idea being a fairly small trench system from WW1 with a fairly sized section of No Mans' Land. Fairly simple, and I have everything planned out... Except for the trenches themselves.

I've been toying around with countless methods to get a trench system going, but none of them have worked out very well at all. 
The best I've gotten so far is using a sculpting program to take a plane and carve into it. This however, is not very precise and it's overall just a pain. Especially because the system has a lot of corners and whatnot

my next best idea was to use something like Modos' Mesh Fusion or Blenders Boolean and then bring it over and roughen/'realism' it up with said sculpting, this however is an absolute nightmare and always catches fire. 

So what would someone who isn't an absolute toolbag like me do in this situation?

musashidan

Personally I'd create it modular: 45/90 degree sections, T-junctions, cross-junctions, curved sections. I'd use simple edge extrusion modeling.

There's no need for sculpting, and certainly not booleans. The trenches were lined - or shored - with timber to strengthen the excavation and prevent subsiding/collapse, so this would be more of a hard-surface exercise rather than organic. I'd also build modular terrain pieces(you could utiise some sculpting here for undulations as the ground above the trenches was more often than not quite flat) that can snap into the various trench configurations and can be blended into larger terrain pieces. You can also build modular bunkers, stairways, tunnel sections, and some props like ladders, barbed wire, sandbags, and bridges.

Jubbie112

hmm yeah I suppose making modular pieces would be my best bet. Making the nml a separate piece. My only problem is seamlessly blending everything together, but that'll be sometime to deal with when the time comes I guess. Anyways thanks for the advice!

Eric Chadwick

Test the blending first, in your render engine of choice, before you build a ton of content incorrectly. Better safe than sorry!

Bending normals is one way, but it's a pain to maintain. I'd suggest hiding the seams with support beams and the like.

Good luck! Sounds like a cool project.

Some links that might help.

http://wiki.polycount.com/wiki/Modular_environments

http://wiki.polycount.com/wiki/MultiTexture

Mark Dygert

What about Sweep a spline shape, down a path spline? It is fairly easy to edit a handful of spline verts and have it drastically change the geometry with very little effort. The UVs it gives you are also fairly decent and can tile well.

You could also model out a long straight trench and then pathdeform(WSM) instances of that trench down various path splines. If you need to edit the model you make your edits on the straight trench and the instances update the final model. That saves you form having to edit complex models at odd angles.

cptSwing

^ This might work with an engine's road system even?

Mark Dygert

Yep, it would work in unreal.

Create a landscape component.


Add landscape spline, push it under the terrain and set your width and falloff.
Then deform the terrain to the spline(s). 


In 3dsmax, make a profile spline (pink) and sweep it over a simple 2 vert path spline (blue).

Be sure to set your pivot below the lowest point of the trench, because that point will be placed on the spline in unreal.


Then in unreal, under the spline segments, define your trench mesh(es).

Your trench meshes can be more complex than what I have, it can include dirt lumps and clumps as well as boards and clutter.

You can have a few different types defined in the meshes array to break up the repeating patterns, just make sure they tile correctly.

Also Knowing that Unreal will merge the edge verts and distort meshes a bit as it weaves around corners. You'll have to play with it a bit to get it working how you want but this is the basic principle.

You can also use the splines to place objects a long the trenches, ladders, pipes, support walls ect...

If you really wanted to dig into it, you could make some blueprints to automate a lot of this process and manage a lot of splines at the same time, similar to a lot of the road generation BPs that handle Y and T junctions, then sell it on the marketplace! lol

More info about creating landscape and splines in unreal.
https://docs.unrealengine.com/en-US/Engine/Landscape/Editing/Splines

cptSwing

Great post!! ^