Just to copy our helpdesk conversation here for others' use:
When you connect a child river to a parent, the child river is forced to flow into the parent as a tributary. This is usually what you want; a tributary flows into its parent. Since that relationship is forced, the option to flip the river direction is removed.
While the opposite sometimes does exist in real life (so called 'distributaries'), it is relatively rare and occurs mostly near river deltas, etc, where flow splits apart. The manual river system supports only tributaries at present.
Are you looking to "simulate" trees in World Machine by including them into the terrain or texture created from WM, or drive vegetation in your renderer with a weight map?
For the first, there is a macro included with recent World Machine builds called "Vegetation Scatter" that will do what you want; feed it your existing texture and a weightmap governing how to distribute the vegetation.
For the second, the latest build 3025 'Alpine Lakes' includes a Select Wetness device that is great for plant placement as it produces an index of soil wetness; otherwise, try using the erosion flowmap output for a similar effect.
This is something I've pondered for a long time, and in fact some customers do successfully use WM Pro in the cloud with its tiled builds / scripting functionality. However, that workflow could charitably be described as "experimental" right now.
It's not likely this year, but it is something I'd love to see for both pro and indie users.
Hmm, something is definitely going wrong here, hopefully we can iron it out quickly! A few questions:
1) What build of World Machine are you running? (Listed in Help->About World Machine if you don't remember) 2) In the Preferences->Build Options dialog, are you saying the slider only has a single notch of 1/1? Or that when set to 2, you only have one build thread functioning? 3) With World Machine closed, open the file "%APPDATA%\World Machine Standard\world.ini and find the line System_thread_max= . Make sure that it is set to 2, and save. Open World Machine, and try building a world. Do you get both threads functioning?
There are a couple routes here, depending on what you want. But essentially, you need to create a material in UE4 and apply it to your landscape.
1) Export a high res terrain texture from World Machine and apply that material to your terrain. 2) Export weightmaps and use to choose between landscape materials.
Creating a landscape material for UE4 is an entire conversation to itself, mostly unrelated to World Machine. But essentially for #1 you can create a texturemap-based material just like you'd create for any other object. For #2, you'll need to use the landscape material system. Here's a workflow guide for doing so:
Agreed - raw files are usually good only as a last resort. However, usually 8 bit height maps are insufficient vertical precision and thus not very satisfactory. Are you sure you want to use these over 16bit PNGs? Regardless of its suitability for terrain, I agree, at a minimum it would be useful for masks and such. Will put it on the feature request list!
If you're using the development version, this can be done easily by using a radial gradient generator in localspace, and an instance placer.
Create a radial gradient device, right click, and select "Quick-set spatial type" to Localspace. Create an instance placer device, and connect the radial gradient to the input. The radial gradient is now tiled across all of worldspace; you can adjust the sizing, etc within the placer device.
Generally speaking, you really wouldn't want filters applied on a per-tile basis in almost any reasonable situation, as there would be no transitional areas or cohesion to the terrain; everything would change abruptly at tile edges.
I think what you most likely want to do is use a Layout Generator or selectors (Height based, etc) to direct where to apply certain effects. You can turn on an overlay in the Layout View to show you where the tile boundaries lie; you can use this information to help plan where to draw your shapes.
Let me know if you need me to go into greater detail on this method, or if you're trying to do something else completely from what I"m talking about above..
The terrain color is currently based only on the terrain itself. To add a color for the road, add a Color Generator and a Chooser device.
Wire the current texture output of the Basic Coverage macro into the first input of the chooser, the color generator into the second, and the mask output of your road layout into the third.
Finally, wire the output of your chooser into the second input of the overlay view, in place of the Basic Coverage device. The areas covered by road will now contain the color you've specified for the road in the color generator device.
The easiest way to insert your roads is to place the Road layout generator directly after the Erosion->Curves sequence -- this will ensure that your roads are placed after the terrain itself has been formed.
There are some quirks while using Parallels which means that I cannot recommend it as a supported configuration for anyone. Speaking unofficially, I often use World Machine successfully in that configuration myself, but it is notably slower than running under Windows directly, and a few things work quite badly, including lighting in the 3D views and some problems viewing the results of large resolution terrains.