public override void OnUpdate(World world, int x, int y, int z)
{
// Get all kinds of required data
var type = world.GetBlockType(x, y, z);
var groundtype = world.GetBlockType(x, y - 1, z);
var metaData = world.GetBlockData(x, y, z);
var height = GetHeight(metaData);
var isFalling = IsFalling(metaData);
var onWater = groundtype == SourceType || groundtype == FlowingType;
// Still water drains and has some restriction the way it can flow:
// 1) It can't flow on top of water tiles
// 2) It can't spread if it is falling
if (type == FlowingType) {
// Not falling tiles adjust their size depending on their neighbors' height
if (!isFalling) {
var maxNHeight = FindMaxNHeight(world, x, y, z);
if (maxNHeight >= height) { // this block is higher than our highest neighbor and needs to shrink
// If this already is the smallest block, disappear, otherwise shrink by 1
if (height == MaxHeight)
world.SetBlockType(x, y, z, (int)BlockType.Air);
else {
world.SetBlockData(x, y, z, height + 1);
ActivateNeighbors(world, x, y, z);
ActivateBlock(world, x, y, z);
}
return;
} else if (height != maxNHeight + 1) { // this block needs to grow
// Never grow higher than the max height
world.SetBlockData(x, y, z, Math.Min(MaxHeight, maxNHeight + 1));
ActivateNeighbors(world, x, y, z);
ActivateBlock(world, x, y, z);
}
} else {
// Falling water shrinks if there is no water block above it
var aboveType = world.GetBlockType(x, y + 1, z);
if (aboveType != FlowingType && aboveType != SourceType) {
// Falling water shrinks faster than normal tiles
if (height >= MaxHeight)
world.SetBlockType(x, y, z, (int)BlockType.Air);
else {
world.SetBlockData(x, y, z, MaxHeight);
ActivateNeighbors(world, x, y, z);
ActivateBlock(world, x, y, z);
}
return;
}
}
// Flowing water doesn't spread on top of water
if (onWater)
return;
}
// Set height of all following tiles and abort if this tile is already the smallest
height++;
if (height > MaxHeight)
return;
// Source blocks also spread on top of water
bool flowDown = DoFlow(world, x, y - 1, z, 8);
if (!flowDown || (onWater && type == SourceType)) {
// Try flowing towards the nearest drop in 4 tiles radius
if (!FlowRadius(world, x, y, z, 1, height))
if (!FlowRadius(world, x, y, z, 2, height))
if (!FlowRadius(world, x, y, z, 3, height))
if (!FlowRadius(world, x, y, z, 4, height)) {
// No nearby drop down, flow in all directions
DoFlow(world, x - 1, y, z, height);
DoFlow(world, x + 1, y, z, height);
DoFlow(world, x, y, z - 1, height);
DoFlow(world, x, y, z + 1, height);
}
return;
}
if (flowDown && y == 0)
return;
// Schedule new update for this block if we flowed once (down or sideways)
ActivateBlock(world, x, y, z);
}
