Atlas - The FlightGear mapping utility  
   Produce and display charts of the world for users of FlightGear, an open source flight simulator. Includes map creator and atlas viewer. Can also be used stand alone. Under development, GPL. [Win32(cygwin),Linux]
   http://atlas.sourceforge.net/

Blueberry3D  
   A program for designing and creating virtual landscapes utilizing real map data or synthetic data from fractals. Fractals are also used to dynamically extend the data and level of detail. [Win 98/SE/Me/2k]
   http://www.blueberry3d.com/

G-Graphix  
   Makers of G-Vista, G-Scene, G-Render Library, software components for CD-ROM/DVD-ROM/Web-productions to interactively fly over huge contiguous terrains. Target market: high end professional.
   http://www.g-graphix.de/english/home/index.htm

Genova  
   Premier demonstration site for G-Vista Web technology. '3D Flight Over Switzerland' uses 25 meter satellite imagery to build 3D scenes to be streamed and visualized over the internet.
   http://www.geonova.ch/home_en.htm

The Aeliom Portal  
   Aeliom allows real time generation, rendering, illumination, and exploration of 3d virtual landscapes.
   http://www.iluac.com/aeliom/

nineteen70five  
   Specializes in the import of GIS data sets and creation of a GIS viewer, which allows the user to "fly" over a 3-D image of their data sets.
   http://mzone.mweb.co.za/residents/jhammes/main.htm

Interactive Visualization Systems  
   IVS of the University of New Brunswick develops software specializes in interactive 3D exploration of ocean floor surfaces, submarine cable routes, and complex climate data sets. Available for download. [Win32,SGI]
   http://www.ivs.unb.ca/

MapRender3D  
   Modeling and visualization software package that creates relief maps in both 2D and 3D using either proprietary global elevation database or public domain DEMs. Features include projections, texture draping, lighting, shading, and elevation color graduati
   http://www.maprender3d.com/

HeightField Lab  
   Generate, manipulate, display, load and save heightfields and then use a raytracer such as POV-Ray to generate the final output image. (free, with code) [Linux]
   http://www.redshift.com/%7eyramin/atp/hflab/

Height Map Editor  
   Free program that edits, generates, and manipulates terrain height maps. These can be used in terrain renders, which are used in games, applications, and demos. Web base manual available. [Windows and Linux]
   http://hme.sourceforge.net/

Natural Scene Designer  
   Raytracing based landscape renderer with object (trees, rocks, lakes) creation, placement and animation capabilities. Interactive planimetric, and 3D modeling viewpoints. Imports USGS and STDS DEMs. [Windows and Mac]
   http://naturalgfx.com/

WorldPerfect  
   A standalone Windows desktop utility for generating high resolution terrain databases from photo-realistic imagery, digital elevation data, and cultural feature content.
   http://www.metavr.com/products/worldperfect/worldperfect.html

Landsraad  
   Alpha version of a terrain editor/viewer for BeOS.
   http://www.geocities.com/stratgis/landsraad/index.html

Leveller by Daylon Graphics  
   Heightfield, bumpmap, and terrain modeler for Windows. Has an active user community with many 3rd party plugins. Downloadable demo with limited functionality.
   http://www.daylongraphics.com/products/leveller/index.htm

Mapper  
   Earth data processing and visualization system. It can combine data from different sources and in varying formats to a single view. It is not an image processing tool but rather builds a 3dimensional model of the earth. [Win95/NT] 1997
   http://www.geocities.com/TimesSquare/1658/mapper.html

World Construction Set  
   Professional photorealistic terrain modeling, visualization, rendering and animation program. Create stunning, photorealistic images and animations with image object rendering. [Win9x/NT/2k/Mac/SGI]
   http://www.3dnature.com/index.html

OBVIO  
   A free win32 3D viewer which demonstrates Dynamic Level of Detail (DLOD), based on OpenGL and GLUT, only reads USGS DEMs. Appears to be in active development.
   http://www.geo-visualisierung.de/demo.htm

Virtual Terrain Project  
   Promotes development of tools for constructing any part of the real world in interactive, 3D digital form. CAD, GIS, visual simulation, surveying and remote sensing. (free, with code) [win32, unix]
   http://vterrain.org/

Vista LSS for Windows  
   3D views and realtime virtual tours with textured and heighted features. Built on Terrain LSS, which provides 'Field-to-Finish' DTM system for surveyors and engineers. [Windows]
   http://www.mccarthytaylor.com/vista.htm

OpenSkies Training System  
   Free authoring tool for virtual environment training system. A low cost PC-based system which incorporates trainee performance measurement capability. [Win9x/NT/2k]
   http://www.openskies.net/training/index.html

TerrainEditor  
   Create landscapes and texture them. Features include: Mesh sizes up to 2048x2048, 3DExploreView for normal FPS viewing and movement, Fractal Brownian Motion (fBm) Heightfields using Perlin Noise. An open-source, OpenGL-MFC program, by NEB Software.
   http://www.nebsoftware.com/Terrain.html

TerrainPro by MultiGen-Paradigm  
   Produce large area terrain databases with real-world data and 3D culture (eg. roads) and imagery, skin generation, and texture mapping. Target market: Professional [Win98/NT,SGI]
   http://www.multigen.com/products/terrpro.htm

TerraVision by ART+COM  
   These guys have big ideas: "A complete virtual 1:1 map of the earth." and "In a nutshell, ... the ultimate information system enabling seamless travel through space and time." Available in German and English. [Requires Flash]
   http://www.artcom.de/cgi-bin/index.cgi?tpl=frame&navName=IE&language=en&id=2_3&res=782&resH=636

SpatialAce  
   Toolkit for building interactive real-time applications with 2D or 3D presentations, from simulators and command and control (C3I) to surveillance and traditional GIS systems. [Win9x/NT/2k]
   http://www.spatialace.com/

OpenGL Terrain Engine  
   An experimental OpenGL interactive terrain viewer with surface textures, clouds and reflective water capabilities. (free, with code) [Win32]
   http://ohad.visual-i.com/exper/exper.htm

Wilbur  
   Small program for playing with terrain data (height fields). Imports data from and to many popular file formats. Can use a number of image processing operations and height field painting tools. (Free, no code) [Win9x/NT]
   http://www.ridgecrest.ca.us/~jslayton/software.html

InReality (tm) Model Viewer  
   Visualization tool that permits the user to view RealSite (tm) models within a virtual environment. [IRIX, Win32]
   http://www.govcomm.harris.com/realsite/

3DEM  
   Interactive OpenGL 3D viewer with flyby and animation capabilities. Reads most familiar US DEM formats and can export to common image and terrain formats. [Win95/98/ME/2000]
   http://www.visualizationsoftware.com/3dem.html

KLevel Heightfield Tool  
   A heightfield modelling tool designed to mimic Leveller for Windows. It features an OpenGL preview and many brush-like tools. (free, with code) [Linux]
   http://sourceforge.net/projects/klevel/

UrbanModeller  
   Software for visualisation of non-tangible data related to the urban environment. It may be used to construct 3D thematic 'maps' such as land use. A component of the Virtual Field Course from the U. of Leicester. [Win9x/NT/2k]
   http://www.geog.le.ac.uk/vfc/software/urbanmodeller/index.html

Generating Terrain  
   An older (1996) collection of documentation, source code, and programs for generating and visualizing terrain.
   http://www.geocities.com/Area51/6902/terrain.html

Demeter Terrain Rendering Engine  
   A cross-platform, open source terrain rendering engine. Written as a stand-alone compnent that can be easily integrated into any kind of application. [OpenGL]
   http://www.terrainengine.com/

TechNature Library  
   A collection of rendering, mathematics, and texturing functions that use fractals to "grow" everything from plants to planets with seamless procedural textures. (shareware, with source code) [Requires DirectX 6.0+]
   http://www.tanzanite.to/

Terrain Modelling  
   A number of scholarly pages covering visualization techniques, terrain morphing, generating fractal surfaces, data filtering, and a mars planetary model. (free, with code)
   http://astronomy.swin.edu.au/pbourke/terrain/

Skyline Software System  
   A complete, modular software collection to serve photo-based 3D interactive environments over the internet or intranets. (free, no code) [Win9x/NT/2k]
   http://www.skylinesoft.com/corporate/corporate_home.asp

TerrainView-Web  
   Plugin for Microsoft Internet Explorer to allow interactive visualization of high-resolution 3D terrain data directly over the internet.
   http://www.viewtec.ch/techdiv/terrainviewwebplugin_e.html

VistaPro  
   Create 3D landscapes using real-world data from the United States Geological Survey and extra-terrestrial data from NASA. [Win9x+]
   http://www.vendornation.com/*ws4d-db-query-QuickShow?vp001