Effect (dimension)

In custom dimensions, an effect is a set of rendering features utilised for defining a dimension's atmosphere and visuals.

Elements
The dimension effect governs the following things:


 * Cloud level
 * Whether the dimension has ground
 * The sky type to be used
 * Whether to always use a bright lightmap
 * Whether the ambient light level is constant
 * Fog color

Examples
Note that as of Java Edition 1.16.5, all effect features are hardcoded, and new ones cannot be created without mods. Dimensions created using effects from existing modded dimensions tend to carry dimension effects to the respective dimension as expected.

minecraft:overworld
The Overworld has the following effect elements:

The fog color is affected by the time of day. The new color $ C$ can be calculated using the following formulae, where $T$  is the time of day and $ \left[ {\begin{array}{c} a\\ b\\ c\\ \end{array} } \right]$ is the existing color.
 * Cloud level: 192
 * Has ground: true
 * Sky type: NORMAL (sun, moon, stars etc.)
 * Force bright lightmap: false
 * Constant ambient light level: false
 * No fog apart from view distance fog

$$A=\max(0,\min(\frac{1}{2}+2\cos(T\times2\pi),1))$$

$$ C= \left[ {\begin{array}{cc} a(0.94A+0.06)\\ b(0.94A+0.06)\\ c(0.91A+0.09)\\ \end{array} } \right]$$

minecraft:the_nether
The Nether has the following effect elements:


 * No clouds (cloud level: NaN)
 * Has ground: true
 * Sky type: NONE (no celestial bodies)
 * Force bright lightmap: false
 * Constant ambient light level: false
 * Has fog

The fog color is not affected by the time of day as the nether has no daylight cycle.

minecraft:the_end
The End has the following effect elements:

The fog color is not affected by the time of day as the end has no daylight cycle, however each RGB component is multiplied by 0.15.
 * No clouds (cloud level: NaN)
 * Has ground: false
 * Sky type: END (no celestial bodies, purple spotted sky texture)
 * Force bright lightmap: true
 * Constant ambient light level: false
 * No fog apart from view distance fog