Fluid

Liquids are blocks that can form pools, streams and even oceans, can flow and spread out over an area, form falls, and allow for swimming and floating.

Liquid properties


There are currently only two liquids in Minecraft: lava and water.

Flows of liquid always start with a source block, a liquid block that is completely full. Source blocks that are completely confined by other blocks (solid or liquid) cannot start a flow and will render as still water with a bit of sparkly animation. Source blocks that are at least partly un-confined will give rise to a flow that will spread out according to the nature of liquids, as described on this page. The liquid blocks in the flow are less full the further they are from their source, and render with animated lines that show their direction of flow. Flows can interact with each other, and with blocks and decorations they pass by or over. They also exert pressure on objects floating in them, carrying them along or down, and in the case of mobs, possibly trapping them.

Flowing liquid has a speed value that governs how fast the spreading effect takes place. Lava in the overworld is much slower than water, but in the Nether it moves at the same speed. Liquid flows can also affect blocks they flow over or past, according to the properties of those blocks and of the liquid.

It is not possible to obtain the liquid as an item, but a source block can be held using a bucket.

Liquid depth
Liquids have a depth value that gives the amount of its block that is empty. A source block is completely full and has depth value zero. Flowing blocks next to a source have an "emptiness" of one more than the source's depth, so one. As a flow spreads from a source the blocks in the flow are more and more empty till they reach the maximum value of 7, where the flow stops. Liquid flows always have a minimum depth of one lower than the surrounding liquid blocks.

Lava in the Overworld has a maximum depth of 3, but in the Nether lava it behaves nearly like water and has a maximum depth value of 7.

Liquid spread
Once a source block is placed the liquid spreading procedure begins by considering the block directly below the source. If that is an air block it is changed to be a block of the same liquid with a depth value of 1 and added to the collection of blocks involved in the spreading process. The source block is removed from the collection as the only possible flow from it is downwards. If the block below is a non-solid block that is affected by a flow it is either destroyed or converted to an item (according to its properties), and then the block beneath is treated as a block of air. Solid blocks and some non-solid blocks are not affected by liquids, so no flow can go that way.

If the block under the flow is deemed to be solid or the block is the main source block, the procedure continues by considering the four blocks around the source. If any of the four are air blocks, or transparent blocks that will be affected, they are changed to blocks of that liquid and are assigned a depth value one greater than the source's if that value is less than the maximum depth, then added to the collection. The source block is removed from the collection as it need not be considered further.

Blocks in the collection with a depth value less than the maximum need to considered as possible origins for further spreading, while those at the maximum are limit of horizontal spreading and are removed from the collection. Note that if all four surrounding blocks are solid the spreading procedure stops as there is no where for a flow to go.

Flow direction
The shape of the ground around a flow is considered for aesthetic effect when evaluating its spread to give preference to the creation of water/lava falls. During the evaluation of horizontal spread the 5 block area around source and flowing blocks is checked for air blocks one block down from the liquid block. These air blocks, and the blocks that lead to them, are all converted to liquid blocks with depth level of 1 greater than the current block to establish a simple flow, but are not added to the collection for later consideration.

For example, the flow of water from a single source placed within 7 blocks of an edge will be only one block wide to the edge, and then will fall as a one block wide stream.

In the overworld this rule means that the flow from a lava source near an edge further than its maximum spread will remain one block wide in the direction of the edge, but not reach it.

Dripping
When particles are enabled, solid blocks that have air below and liquid above will drip as a visual indication that one thin layer of ceiling blocks are all that is keeping the player dry. Dripping lava does not cause damage or start fires. It can take several seconds before dripping starts.

Liquid updates
There are some types of block updates particular to liquid blocks:
 * Another block is placed into it's space
 * Liquid starts to flow in from an adjacent block
 * An established incoming flow stops

Liquid blocks are considered as "empty" when a player tries to place a block, so the placement always succeeds. This means that liquid source blocks can be destroyed by filling the source with any other type of block. Water sources can even be destroyed by placing a torch which leaves the block empty as the water has time to wash the torch off of its placement before it is converted into air. Lava sources can only be filled in by solid blocks of course.

Generated structuress never cause block updates to adjacent liquids when they spawn. For example, a cave entrance that is created partly below water level at the edge of a body of water/lava will not cause the liquid to flow until it receives a block update. On the other hand, liquids created as part of structure will flow immediately if not completely confined, like holes in the bottom of an ocean that open into a cave below.

Gallery
Flüssigkeit Líquidos Fluides 液体 Vloeistoffen Ciecze Жидкости 液体