Distant Horizons is a mod for Minecraft

What does Distant Horizons do?

Distant Horizons allows you to see the distant landscape beyond the usual drawing distance. For remote areas, simplified LOD models are used, so the horizon can extend over hundreds of chunks.

Why is the horizon getting further?

Minecraft's usual drawing distance limits the number of full-fledged chunks that the game brings around the player. Distant Horizons creates simplified representations of a remote landscape called LOD. Mountains, coastlines and large structures remain visible far beyond the boundaries of conventional rendering, although remote areas are not treated with full detail of the nearby chunks. This is a way of displaying the world, and not increasing the distance of all game mechanisms.

How a distant landscape is formed

Fashion needs data about the terrain: as it explores, it remembers and builds simplified geometry. Therefore, the first discovered territory and the already studied world can look different. At high ranges, the load on video memory, disk and computing increases; there is no infinite free review. For beautiful panoramas with shaders, you need to separately check the support for Distant Horizons in the shaderpack itself and the compatible version of Iris.

What fashion doesn't do

The remote silhouette of a mountain on the horizon does not mean that mobs, machinery or farms are working on it at this moment. The LOD is designed to depict a remote world, not a complete simulation of all the chunks into hundreds of blocks around the player. Screenshots of developers usually show specific values of normal and LOD-range – these numbers are important to distinguish.

Primary source: developer-page.