What is the purpose of a color gun in GIS technology?

The purpose of a color gun in GIS technology relates specifically to the display of digital images. A color gun uses the red, green, and blue (RGB) color model to create various colors by combining these three primary colors in different intensities. When a color gun projects pixels on a screen, it mixes different amounts of red, green, and blue light to produce the full spectrum of colors that we perceive on a digital display. This is foundational in map-making and rendering in GIS, as it allows for a wide range of colors to be used in visual representations of geographic data, enhancing the interpretation and analysis of spatial information.

In this context, other options do not align with the primary function of a color gun. The color gun does not specifically measure temperature variations, capture three-dimensional images, or enhance brightness; its fundamental role is in the accurate display and generation of color through the RGB system.