26.1.2 Mob Crowd Overdraw Defense

👥 Mob Crowd Overdraw Defense (Minecraft 26.1.2)

Dense mob farms, villager trading halls, and animal breeding pens can cause extreme framerate drops when hundreds of entities are stacked within a few blocks. While GPU Early-Z rasterization handles basic depth testing, extracting and submitting hundreds of mob skeletal hierarchies overloads CPU render dispatchers.

Camera Culling provides an optional, safeguarded crowd overdraw defense system.

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📋 Mob Crowd Defense Infobox

Property	Value
Config Key	cullEntitiesBehindEntities (Default: false)
Cluster Density Cap	maxEntitiesPerCluster (Default: 8 mobs / 1.5 blocks)
Distance Fast-Fail	$> 16.0$ meters ($256.0\text{m}^2$)
Cluster Search Radius	targetBox.inflate(1.5)
Exempt Entities	Transparent / Decorative mobs (Vex, ArmorStand, ItemFrame, Slime, MagmaCube)

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🛑 16-Meter Distance Fast-Fail Architecture

In large open fields with dispersed cow herds, running spatial queries across all mobs causes unnecessary CPU overhead. In modern versions of Camera Culling, crowd overdraw culling enforces an immediate 16-meter distance fast-fail:

public static boolean isEntityOccludedByCloserEntities(Entity target, Level level, Vec3 camPos, AABB targetBox, double targetDistSq) {
    if (target == null || level == null || camPos == null) {
        return false;
    }

    // Fast-fail: only apply crowd overdraw culling within 16 meters
    if (targetDistSq > 256.0) {
        return false;
    }

    // 1. Cluster Density Cap in tight 1.5-block sphere
    int maxCluster = CameraCullingConfig.getMaxEntitiesPerCluster();
    AABB clusterBox = targetBox.inflate(1.5);
    List<Entity> clusterEntities = level.getEntities(target, clusterBox, 
        e -> e instanceof LivingEntity && !isTransparentOrDecorative(e));
    
    if (clusterEntities.size() < maxCluster) {
        return false;
    }

    int closerInCluster = 0;
    for (Entity e : clusterEntities) {
        double distSq = camPos.distanceToSqr(e.getX(), e.getY(), e.getZ());
        if (distSq < targetDistSq) {
            closerInCluster++;
            if (closerInCluster >= maxCluster) {
                return true; // Culled due to cluster density cap
            }
        }
    }
    return false;
}

Benefits:

1. Zero Open-Field Overhead: Mobs grazing beyond 16 meters skip entity search sweeps entirely.
2. Dense Pen Protection: In 1x1 or 2x2 mob grinder pens where 50+ cows/zombies are packed, rendering is capped to the frontmost 8 entities, eliminating lag spikes.

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🔗 Related Pages

• Entity Occlusion Culling
• Boss & Blacklist Immunity
• Return to MC 26.1.2 Overview