Heightmaps

Heightmaps are a type of raster data used to store elevation information. Each cell (pixel) contains a value indicating the height at that location. In its simplest form, a heightmap is a grayscale image, where darker values represent lower elevations and brighter values higher elevations. Multichannel or color heightmaps can encode elevation or additional attributes with color.

In 3D graphics and GIS, heightmaps are converted into terrain models by creating a grid of vertices whose vertical coordinate corresponds to the height value scaled to a real-world elevation range. Adjacent grid points are connected to form triangles or quads, producing a terrain mesh. The mesh can then be shaded, textured, and rendered with lighting, and further refined with smoothing, filtering, or level-of-detail techniques.

Common data sources include digital elevation models from satellites or aircraft, LiDAR, and photogrammetry. File formats for heightmaps include PNG, TIFF, and RAW, typically with 8- or 16-bit depth. Height information may be georeferenced with world files or embedded metadata to place the terrain in a geographic coordinate system.

Color heightmaps, or colormapped heightmaps, map height values to colors to aid visualization, while separate normal maps or shading models provide lighting cues for rendering. Applications span geographic information systems, landscape design, game development, procedural terrain generation, and environmental simulations.

Limitations include resolution constraints, interpolation artifacts, and the fact that a heightmap encodes only surface elevation at grid samples, omitting fine-scale features and subsurface structures.