When draping an image over a digital terrain model, what is typically adjusted?

When draping an image over a digital terrain model, adjusting the z-values to match terrain heights is essential for achieving a realistic representation. Digital terrain models (DTMs) provide elevation data, which is crucial to reflect the topographical features accurately. If the z-values of the draped image are not aligned with the elevations from the terrain model, the image can appear distorted, misplaced, or simply unrealistic in relation to the terrain. By matching the z-values, the image follows the contours of the terrain, creating a more accurate visualization that integrates both the surface and the visual elements effectively.

In the context of the other options, adjusting the color saturation of the image does not directly contribute to the accurate representation of the image on the terrain model, while scaling the image may help fit its dimensions to the area of interest but does not ensure that it accurately drapes over varying elevations. The resolution of the final output is relevant for visual clarity but does not affect the fitting of the image onto the terrain itself. Thus, focusing on z-values is key to properly draping the image over the digital terrain model.