Make levels using Blender?

[LeiGet]

Hi. I'm a long-time Blender user and was wondering if it's possible, in part or in whole, to use Blender to make levels, mostly the level geometry. I understand that NPC, scripting, partitioning, etc would be something better done in DarkRadiant, but I'd like to use Blender to make the buildings, streets, terrain, etc and to place them.

[nbohr1more]

Yes, this is possible but there are a few things that make it a little impractical.

1) Models do not seal the void so you need BSP brushes behind or inside models to properly seal a map. As I recall, there are doom 3 and quake map exporters that can export your initial block-out geometry as standard brushes so you could do both modeling and brushwork in blender. You’d just have to do it in phases

2) Visportal placement is crucial to performance so you will need to ensure you blender models are cut at portal boundaries so that you can setup brushes and visportals at choke points to prevent rendering outside the player view area

3) model geometry is often too complex for the physics engine. You will need to make invisible clip models or clip brushes that use a more simplified structure to ensure AI pathing and overall collision physics perform well.

4) Models need to be split at light boundaries. If a single light touches a model the engine will do light geometry calculation for the whole model. If enough lights hit a large model it can severely impact performance. Brushes will auto-split on light boundaries but often split in less optimal locations so it has become the convention to use func_static geometry to force brushes to split in the preferred locations

5) blender has no knowledge of specialty brushes like fog volumes, water, SEED auto dispersal etc

So it’s possible to do the majority of mapping in blender but ultimately you will need to use Dark Radiant to do the finishing touches

The current paradigm is to create modular content in blender and then assemble the modules together in Dark Radiant along with bsp caulking and vidportal placement 

 

[HMart]

1 hour ago, LeiGet said:

Hi. I'm a long-time Blender user and was wondering if it's possible, in part or in whole, to use Blender to make levels, mostly the level geometry. I understand that NPC, scripting, partitioning, etc would be something better done in DarkRadiant, but I'd like to use Blender to make the buildings, streets, terrain, etc and to place them.

nbohr1more already said most of it but if I can add anything, is that the AI traversal system called AAS (Area Awareness system) also requires brush's to work.  

Spoiler

This is what I know about it, others may correct me if something is wrong, AI will walk fine on a complex floor model made in blender but bellow the model, you need a brush for the AI to be able to traverse the space, the brush doesn't need to be accurate to the floor mesh and the AI doesn't need to contact the brush at all, so you can just put a flat brush a few units bellow the floor model, the AI just needs it there to know where to go next, because its AAS system (navigation system) totally ignores mesh's, is like they aren't there at all. This means AI afaik will also bump into mesh based static models in it's path, like headless chickens, if you don't enclose those, in a brush using the special monster_clip texture. My two cents.

 

[Wellingtoncrab]

I have seen this addon mentioned on the idtech 4 discord regarding exporting doom 3 brushes from blender in the .map format which might let you accomplish some of what you want as far as building level geometry in blender. Haven’t tested it personally for tdm:

https://github.com/c-d-a/io_export_qmap 

[nbohr1more]

I should have posted this link but my previous reply was posted from my phone:

https://wiki.thedarkmod.com/index.php?title=Modular_Building#Modular_Building_Technique

[jonri]

15 hours ago, nbohr1more said:

4) Models need to be split at light boundaries. If a single light touches a model the engine will do light geometry calculation for the whole model. If enough lights hit a large model it can severely impact performance. Brushes will auto-split on light boundaries but often split in less optimal locations so it has become the convention to use func_static geometry to force brushes to split in the preferred locations

Is this still true now that 2.11 is out with this feature?

I've been wondering about whether this might open up the possibility to use larger models for things other than terrain, for example modeling a building at a time in Blender and then assembling them into a street in DR.  I'll probably at least test it out someday...

[Arcturus]

There are .map exporters for older versions of Blender. I once made this in Blender:

 

[Arcturus]

On 2/17/2023 at 5:14 PM, Wellingtoncrab said:

I have seen this addon mentioned on the idtech 4 discord regarding exporting doom 3 brushes from blender in the .map format which might let you accomplish some of what you want as far as building level geometry in blender. Haven’t tested it personally for tdm:

https://github.com/c-d-a/io_export_qmap 

I tried it and it's much nicer to work with this version of the addon and Blender 4.3 than it was a decade ago with the old ones. At first I thought it won't work at all, because the .zip file couldn't get registered in Blender. But I installed just the .py file and it worked.

Then I had to find out which settings will work. Flags needs to be set to "Quake 2". It adds "0 0 0" at the end of every line, who knows what for. Without it, it won't load into Darkradiant.

Object types / Mesh set to "Brush" when exporting full brushes. Each polyhedron needs to be a separate object in Blender. When exporting flat faces, then the faces can be connected and part of the same object. In that case set either "Shell" or "Walls" — that will extrude them automatically.

It's best to snap everything to grid in Blender and leave Grid set to 0. When you use higher values, the addon will try to snap brushes to grid which can cause misalignment on complex geometry.

Put the name of the Darkmod material in the material slot:

EDIT:

One more thing I noticed is that there is a tab in Object Properties where user can specify type of geometry for each object individually.

This setting will override global export setting. This way one can export multiple objects at once, each as a different type. From the exporter's page:

[Arcturus]

Turns out long material names will be cut short on export...

Anyway, I made a simple staircase generator in Blender's "geometry nodes":

darkmod_stair_tool_v1.00.blend

It's probably best to stick to multiples of 4 (step count) for nice round values of the diameter.

• set values
• apply the modifier
• separate as objects by loose parts
• export stairs as "brush", side walls as "shell", top and bottom as "walls"

Here in the video side walls were exported with "walls" option, that's why they look like this.

 

[kingsal]

Wow!
That's awesome and might be a good way to quickly make complicated level geometry. 

[Arcturus]

@kingsal

Just be careful, or you might get the NPCs confused. Here I just added "simple deform" modifier in Blender to taper the tower. I think the step at the top is too tall.

I recently saw NPC falling to his death in similar fashion in one of the missions.

 

Edited August 20 by Arcturus

[Arcturus]

Here's a more extreme example, although it took some time to get it to work.

Probably not very practical. There aren't many cases where you would need BSP this complex. I was thinking perhaps if you wanted to show the vaulted ceiling both from the bottom and from the top.

 

[nbohr1more]

I still feel that brushes should be mostly reserved for simplified collision, monsterclip and map sealing \ caulk due to the inherent performance liabilities of making complex BSP designs.

However... I would love to see some wild texture bake across a large \ complex brush design that puts vertex blended transitions to shame. Downside is that the texture size would be pretty large which would cause it to look pretty nasty for low-end players who use image_downSize for performance.

[Arcturus]

4 hours ago, nbohr1more said:

I still feel that brushes should be mostly reserved for simplified collision, monsterclip and map sealing \ caulk due to the inherent performance liabilities of making complex BSP designs.

That's the idea. BSP should be simplified when compared to the visible geometry. But if it's too simple, then the visible geometry has to conform. I always looked for a way of building less boxy, angular maps and more organic ones. Keep in mind that those are experiments. I'm looking for the limits of the engine, I'm not saying that the whole map should be this complex. I also think that with this script, building in Blender is a viable option. Back in the Blender 2.7 days I remember I had to use two scripts - one for exporting to Quake .map and one to convert to a Doom 3 .map format. And the geometry would drift apart. It was pain in the ass. This is better.

[Arcturus]

One more thing I noticed is that there is a tab in Object Properties where user can specify type of geometry for each object individually.

This setting will override global export setting. This way one can export multiple objects at once, each as a different type.