With Terragen you have complete control over the shader networks used for terrains, textures, micropolygon displacements, clouds and object distributions. You can reorganize the planetary shading pipeline to suit your goals. Place grass and trees wherever you want, as well as other objects in native TGO or OBJ format that you have modeled in third party software.
Here are some key features of "Terragen":
Cutting-edge adaptive subdivision renderer.
Modular, plugin-based architecture.
Render entire planets, sweeping vistas, tiny rock gardens, or anything in between.
Import 3D objects for rendering. Export high resolution objects.
Render millions of boulders or trees using "instancing".
Add multiple heightfields to your scene. Use procedural terrains that can span an entire planet.
Apply almost "infinite" fractal detail to terrain and other objects.
Overhanging terrain using procedural displacements, image-based displacements, or imported geometry.
Volumetric clouds or fast "2.5D" clouds.
Production quality anti-aliasing and motion blur.
Node graph editor for ultimate control over shaders and textures.
Mac
OS X 10.8 or newer
Intel CPU or Apple M-series (via Rosetta 2 emulation)
Minimum 8GB of RAM - 16GB or more recommended
Minimum 2GHz Dual Core CPU - Quad Core or better recommended
Language : English
Home Page-http://planetside.co.uk/whats-new-in-terragen-4/