--These instructions are mainly for the flat terrain generator, but also apply to the spherical planet.--
You won't need any plugins, it runs on default blender. the files are developed on Blender 2.83.11
This tool only works with Cycles.
Using eevee isn't recommended, the displacement won't work and you get alot of lag because of the complex node setup.
With default settings (for 1920x1080 renders) the planet and the terrain generator use about 5gb of ram for a render
-Using a higher focal length for the camera uses more ram (since terrain thats far away appears larger and will get more geometry by the adaptive subdivision)
-Using a higher resolution for renders will use more ram (since the adaptive subdivision is based on the amount of pixels)
-Using a lower dicing rate for the subdivision will use more ram (since the dicing rate determines how much geometry each pixel will get)
The desert seed setting is disabled in the terrain generator due to shading bugs
The desert amount still works fine
The desert seed works fine for the globe planet.
The terrain generator uses adaptive subdivision by default. it creates polygons based on the distance of the viewer, if the scene's details appears to be too low, try to get out of the rendered viewport and intialise the rendered viewport again.
If you want to see changes happen more quickly, try turning off the subdivision modifier in the viewport
The seed changes alot even if you change it by 0.01
if you set the global seed above 5 or below -5, glitches start to appear
If you can't find the right seed between 5 or -5, try to change the continent seed instead
If you see alot of water at your current seed, try to higher the continent height, if you still only see water, try another seed
The mountain seed makes large mountainranges rotate around their axes, if you don't see anything change, it's probably because you are at a really low global scale.
Tip: when searching for a nice seed, try to put the continent height at 0.85 and the mountain height at 5 or lower, this way you have less chance to get water-only seeds, but still have plenty of flat land to generate cities and fields.
IMPORTANT: with every seed, try to lower the continent height as much as possible, this will create more dynamic landscapes in combination with water and the displaced polygons will be closer to the orginal plane, this way the subdivision surface will work better
All the fields can be turned into cities with the ''cities and downtown settings''.
If you want more forest, try setting the mountain height higher.
To find the nice terrain that fits your needs, it's just a matter of taking time to try out different combinations of seeds and settings. it's a totally random system based on noise.
Feel free to change or use the node setup in any way.