Population maps

Started by james adamson, August 15, 2020, 01:40:53 pm

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james adamson

Hi all.
I put something up here the other day about producing a population map outside of TG. Dune fed back but I got sidetracked.
I have many many buildings and other objects that I need to fill a large area. 2 km :o (maybe Ill see how I go.) So I need to carefully place a number of different populations that appear random so will need a few maps that are scattered over my scene. I am trying to produce a destroyed town so I need to have some sense of order. i.e a hint of roads and a pattern where buildings are/were but also have maps for the debris models I have. Where I am stuck at the moment is the most efficient way to produce population maps that I can previs as colour layouts and adapt easily. I basically do not want to be randomly painting and subtracting pop maps in TG. 
So I have my basic scene but I have no clue as to how I would produce a map in PS that would map onto my scene. 

I guess what I would ideally like is an image map that I could place on my scene that had various colours for specific objects so I can get a good idea of layout which I would then use as a population map
to build my scene.


August 15, 2020, 02:56:12 pm #1 Last Edit: August 15, 2020, 03:00:26 pm by WAS
Since the buildings are rather large, it's possible you can use small dots where you want the POO of an object to reside. Turning off rotation settings would help them fall into a grid order. So you could use a RGB map from PS, where one colour is your roads, another colour your building plots, and another could do something else, like managed dead trees in the parks and roads.

I did similar with my park pathway scene (which is in file sharing) and used a small point to define where the lamp posts go. More or less they were pretty centered.

james adamson

Great stuff. 
Where I am a bit lost, and I think this is pretty rudimentary stuff so bear with me.
But it is how I make the correlation between the PS map and the TG scene. Would I need to render out some flattened version of my TG scene to pull into PS?


I'd imagine you'd just scale the image from PS as you'd like in Terragen.


Here's a quick example I did with this grid

james adamson

I think as usual I am overcomplicating things. Just scale grid in TG.


You could make a heightmap (ortho render with just illumination of altitude, as I described in another thread), and import in PS. Then you'd have a basis to work from, and have an idea about hills and such.
Then make a a layer for each building type, and paint in the mask. If you need very small points to fill with specific objects, you'd need a pretty large map.
Then copy three layers to a new RGB file and copy each layer into a channel. name the file accordingly.
Import in TG, project either by that same ortho camera, or plan Y and set size and location so it fits, then split (convert-blue to scalar, etc), and use for the pops.

james adamson

And I have tried what you suggested a few days back. i.e bringing my buildings straight into TG.
It is so efficient how it deals with lots and lots of objects. It does however seem to get sluggish when adjusting material settings on 
complex models, thats a bummer because it makes adjusting some of those textures unworkable, but the way it deals with instances is amazing.
Cheers for the feedback on the population technique.


James -

I just responded to your other thread but then saw this. I wonder if the large size of your scene is causing the slowdown. You may want to avoid directly editing objects in such a large, complex scene.

One way to do this is to first place each model in its own empty scene. I use a custom default scene for this with no surface displacements and a layer of light overcast clouds to diffuse the lighting. Build and edit the object's shading network there, then export the object as a TGO. In your main scene, place the TGO and tweak the shaders as needed.

Then again, maybe you're already doing this. ;)

james adamson

Funny. This is exactly what I did in Modo when I first got the models. All 108 of them!!!
Looks like I will be doing it again in TG. ::)
Hey ho all part of the process I guess. It will probably work out better than rendering all the elements out from Tg plus the terrain mesh and 360 for lighting then rendering my buildings in modo importing that geometry into my to scene to get the lovely shadows and then comping it all in Nuke! Breath....
Yeah That sounds like hell.

james adamson

No what am I on about? I tried this. I started a brand new scene with nothing in it except one building.
Editing materials was a no go. Rainbow wheel beachball thingy every time I tapped the Ui


Hi James. If you wouldn't mind sending these files to me (either my PM or at our support email) we'll try to figure out what's causing the slowdown.
Just because milk is white doesn't mean that clouds are made of milk.

james adamson

Hi all.
Matt, I uploaded that stuff to the support email.
And I tried out the orthographic projection technique for the population map and it does exactly what I am after. Just colouring areas by altitude render that frame then re projecting with the same camera and it fits perfectly. Thanks Dune.
Just gotta fill the space with stuff now.


Rainbow beachball? You're on mac aren't you? I recently tried it on my server in a VM and it wasn't a very pleasant experience. Lots of crashing, and the server is plenty powerful, and VM enabled for multiple deployments of OS's.

Been a issue for me cause windows 10 on my server is doing weird things. No screensaver, or anything enabled, but if I leave remote desktop, it goes back to login, and closes TG. :(