Just some sloppy notes about rivers… nothing definate here though.
(As usual) I believe at least some of these ideas can be realized with a macro or at least some simple technique.
I guess I can provide a macro for river deltas this evening.
(almost ready but a TG render is blocking my pc right now, so I wasn’t able to test it yet.)
I would definetly like to see some of these ideas in action. SeerBlue
Whatever you can come up with would be greatly helpful. Maybie i can make additional modifications and get several steps closer to this goal.
Some problems appeared with the deltas… I’ll try to solve them.
But for the fillings you can use Combiner -> Max
No Worries. Whatever you may be able to come up with will still help out.
OK, i think I found an acceptable method to create a river delta.
(But not an automated procedure that works on the entire terrain.)
1. screenshot
2. explanation
The basic idea is, that rivers in wm dont usually split up into multiple flows as they run down the mountains. They in fact do exactly the opposite - a lot of flows unite somewhere in a valley:
We want it this way
Water flows from land to sea.
But wm doesn’t work this way - this is what wm has to work with, if we want get this kind of flow map
The green lines indicate mountains.
The final trick is, to produce artificial mountains in order to control…
a) our river - a delta with river is a bit more realistic :mrgreen:
b) the delta itself, which is produced by generating mountains into the sea
But our terrain is more or less totally useless, since what is supposed to be a huge lake or ocean is yet filled with highlands.
The simple solution is to add a heightfield to control the flow of erosion - and substract it again afterwards.
Here is the tmd-file:
http://nicokorn.de.vu/worldmachine/stuff/riverdelta.rar
I hope that helps getting a bit closer to realistic rivers 
can’t wait to give it a go, a simple but sensible solution, as in the eal world obstructions are what changes the flow, so mts in and nts out will work. SeerBlue
A very clever idea!!
The only drawback is that it generates a bit of erosion perpendicular to the main river… …Which, curiously, is something I don’t see in your render! but I tested it at a lower resolution… Could have been that.
Another detail is that delta rivers tend to produce wider channels, and controlling the width of a channel in WM is hard… 
A very clever idea!! The only drawback is that it generates a bit of erosion perpendicular to the main river..In my first network there were such rivers... but I was able to remove them by using a different shape to add. :)
These river delta sets are very cool. It gave me some ideas for the mountain to desert terrain i just put up as i was playing around with the settings so it worked out to a great advantage for what i was trying to acomplish.
Another idea i was wanting to play with is having a river channel heightfield mask in photoshop drawn within photoshop or using some other means of software. Inkscape can draw L-Systems and there may be a way to create river-like networks with it’s lindenmayer algorythms. It’s just they would have to be rather large in resolution.
http://inkscape.osuosl.org/screenshots/gallery/inkscape-0.44-lindenmayer.png
I was thinking using this to import into World Machine and layer it over the terrain and use something like a low opacity multiply blend with the combiner device therefore it fades with the highest points (Mountain Tops) and the lowest points (Water)
I took a erosion channel into photoshop using the layer multiply method. It seems like it may work but i have to test it farther to see if this idea works out.
The problems with using external river masks ithat these rivers have to be in valleys.
And these masks usually run cross the terrain over mountains, up and down hills.
So they would have to be a part of heightfield generation. Which is still an idea worth thinking about.
Problem is the random values needed for such systems - you would have to save them which resulted in infinite amounts of data (remember that wm has an infinitetly large world) or you would have to find a function, that provides values that at least look random - like for example the last digits of fibonacci numbers or any other chaotic but calculable function.
But L-Systems might be the answer to the river delta problem indeed.
I see what you are saying, probably in World Machine Pro i could move the mask around into a key location and the drop it there as a multiplied blend into the valleys following the proper paths.
Your River Delta device is a great start, i wonder is the Erosion Device is accesable through the Plug-In Kit?
If the Erosion Device’s inner components can be modified somehow?
Only if Layout Mode allows importing your graphics.
And if not: As always - I believe you can do that with a macro :mrgreen:
Well, we will see what Layout Mode has up it’s sleeve.