MAtmos is a sound atmosphere generator mod for Minecraft. MAtmos examines your surroundings and generates noises based on its database. Examples include birds chirping in the forest, rumbling noises near a lava lake or wind gusts on a hilltop.
MAtmos runs on a database of rules for when each sound should play. The database can be added to and modified.
Enable / Disable - Toggle by pressing the MAtmos key (F7 by default)
Change Volume - Hold the MAtmos key (F7 by default) and scroll up or down using mouse or mouse scroll wheel
Adding your own sounds
It is possible to create your own atmosphere by altering the database. To perform this, you will need to roughly understand how MAtmos works.
MAtmos counts at regular intervals, how many blocks of each type there are. It is scanning a 64x32x64 volume around the player (64 being the height). Rules allow it to draw conclusions. If there are leaves, there are trees. At shorter intervals, MAtmos scans a small volume (36x10x20) and also checks variables like altitude, the amount of sunlight or the weather. Combining conclusions and observations creates atmospheres. Forest with birds is trees and with air while the player could see sunlight with no rain. Environments are enabled whenever a corresponding atmosphere is active. Environments are rules in which to play sounds. Volume, delay, intervals. Rules, atmospheres and environments are all written in a database. You can edit the default database or add a new one.