Bat Ecology and Photophobia

🦇 Bat Ecology, Photophobia & Daytime Roosting

Feature Parameter	Specification Details
Primary AI Goal Class	net.vanillaoutsider.betterbats.ai.BatSleepGoal
Roost Validator Class	net.vanillaoutsider.betterbats.ai.BatRoostHelper
Daytime Sky Light Limit	Sky Light = 0
Daytime Block Light Limit	Block Light <= 7
Roost Search Radius	16 blocks (Horizontal) / 10 blocks (Vertical)
Cluster Preference	Prefers roosting within 5x3x5 blocks of existing resting bats
Supported Roost Surfaces	Solid ceilings, stalactites, lanterns, chains, fences, walls, leaves

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☀️ Daytime Photophobia Mechanics

Unlike vanilla Minecraft where bats randomly fly regardless of time or daylight, Better Bats introduces Photophobia. During daylight hours (level.isBrightOutside()) or when raining while exposed to sky (level.isRaining() && level.canSeeSky(pos)), bats actively seek out dark cave overhangs or covered roosting spots.

                  ┌────────────────────────┐
                  │   Daylight / Storm     │
                  └───────────┬────────────┘
                              │
                    Can see sky / Bright?
                     ┌────────┴────────┐
                    YES                NO
                     │                 │
           ┌─────────▼────────┐  ┌─────▼────────┐
           │ Seek Dark Cover  │  │ Check Roost  │
           │  (BatSleepGoal)  │  │ Surface Type │
           └─────────┬────────┘  └─────┬────────┘
                     │                 │
             Sky Light == 0 &&         │
             Block Light <= 7?         │
                     │                 │
           ┌─────────▼─────────────────▼────────┐
           │     Attach Ceiling & Sleep         │
           │        (setResting(true))          │
           └────────────────────────────────────┘

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🪨 Valid Roosting Surfaces (BatRoostHelper)

Roosting is evaluated via BatRoostHelper.isSuitableRoost(Level level, BlockPos pos, BlockPos above):

1. Solid Ceiling Blocks: Any block with a sturdy bottom face (aboveState.isFaceSturdy(level, above, Direction.DOWN)) or redstone conductor.
2. Pointed Dripstone / Speleothem: Stalactite tips pointing downwards (SpeleothemBlock.TIP_DIRECTION == Direction.DOWN).
3. Hanging Lanterns: Lanterns suspended from ceilings (LanternBlock.HANGING == true).
4. Hanging Chains & Supports: Blocks tagged under #minecraft:chains, #minecraft:fences, #minecraft:walls, and #minecraft:leaves.

public static boolean isSuitableRoost(Level level, BlockPos pos, BlockPos above) {
    if (!level.isEmptyBlock(pos)) return false;
    BlockState aboveState = level.getBlockState(above);
    if (aboveState.isAir()) return false;

    if (aboveState.isFaceSturdy(level, above, Direction.DOWN) || aboveState.isRedstoneConductor(level, pos)) return true;
    if (aboveState.getBlock() instanceof SpeleothemBlock || aboveState.getBlock() instanceof PointedDripstoneBlock) {
        if (aboveState.hasProperty(SpeleothemBlock.TIP_DIRECTION) && aboveState.getValue(SpeleothemBlock.TIP_DIRECTION) == Direction.DOWN) return true;
    }
    if (aboveState.getBlock() instanceof LanternBlock && aboveState.getValue(LanternBlock.HANGING)) return true;
    return aboveState.is(BlockTags.CHAINS) || aboveState.is(BlockTags.FENCES) || aboveState.is(BlockTags.WALLS) || aboveState.is(BlockTags.LEAVES);
}

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🦇 Roost Clustering Behavior

When a bat decides to sleep, it scans a 16-block bounding box for already resting bats. If resting bats are present, it prioritizes selecting a candidate roost block offset within a 5x3x5 neighborhood of its fellow bats, creating natural colony clusters on cave ceilings and under dark structures.

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🔗 Related Pages

• 3D BOIDs Flocking, Altitude Caps & Steering
• Guano Production & Farmland Crop Fertilization
• Dynamic GameRules Reference Table