World Machine - Command powerful tools like erosion and advanced colormaps to create terrain heightmaps, meshes, and textures for your game or 3D scene. Download for Free!
Unity - The multiplatform game creation tools for everyone.
Vue - Create vast expanses of terrains, add trees, select the best point of view and render...
Godot Engine - Feature-packed 2D and 3D open source game engine.
EarthSculptor - EarthSculptor is a realtime terrain height-map editor and paint program featuring an easy to use...
Blender - Blender is the open source, cross platform suite of tools for 3D creation.