What is a Hillshade Map?

A hillshade map transforms flat elevation data into an intuitive 3D visualization by simulating how sunlight falls across terrain. Ridges and peaks catch the light while valleys and depressions fall into shadow. The result is a grayscale image that makes topography immediately understandable — no specialized training required to interpret it.

How Hillshade Works

The algorithm places a virtual sun at a specific position in the sky, defined by two angles: azimuth (compass direction, typically 315° for northwest) and altitude (height above horizon, typically 45°). For each cell in the elevation model, it calculates the angle between the surface normal and the incoming light rays. Surfaces facing the sun render bright; surfaces facing away render dark; surfaces at oblique angles render in intermediate grays.

This simple calculation produces remarkably effective visualizations. Subtle features that are invisible in raw elevation numbers — ancient field boundaries, geological faults, erosion patterns — pop into view when illuminated from the side. The human visual system is extremely good at interpreting shaded relief, making hillshades one of the most powerful ways to communicate terrain information.

Applications

Cartographers use hillshades as base layers that give maps depth and context. Geologists identify structural features and fault lines. Archaeologists have discovered countless sites — Roman roads, medieval settlements, ancient fortifications — by examining hillshaded LiDAR data of forested areas. For reports and presentations, a well-rendered hillshade communicates terrain more effectively than any table of numbers.

Hillshades with LidarVisor

LidarVisor generates hillshade visualizations automatically from your DTM. View them draped over 3D terrain or export high-resolution images for use in reports, presentations, and GIS projects.