Stale Attribute Purging and Scale

Stale Attribute Purging & Scale Math

Bug Fix	Issue	Release
Giant Scale Bug	Stale attribute modifier accumulation	1.8.11
Base Scale Offset	ADD_VALUE attribute modifier base offset math	1.8.10

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📐 Scale Attribute Offset Math

In Minecraft 26.2, entity scale uses vanilla minecraft:scale. When applying an ADD_VALUE attribute modifier for scale, the modifier value $M_{\text{scale}}$ MUST subtract $1.0\text{f}$ from the target scale $S$:

$$M_{\text{scale}} = S - 1.0\text{f}$$

$$\text{Final Scale} = \text{Base Scale } (1.0) + M_{\text{scale}} = 1.0 + (S - 1.0) = S$$

If $1.0\text{f}$ is not subtracted, setting target scale to $2.0$ applies $+2.0$ onto base $1.0$, rendering a $3.0\text{x}$ (300%) unintended giant entity.

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🧹 Stale Modifier Purging in GeneticsEngine

To prevent duplicate attribute modifiers from stacking over world reloads or breeding updates, GeneticsEngine purges legacy genetics_ modifiers before applying new ones:

public static void applyGeneticsModifiers(LivingEntity entity) {
    AttributeInstance scaleInstance = entity.getAttribute(Attributes.SCALE);
    if (scaleInstance != null) {
        // Purge legacy/duplicate modifiers by identifier
        scaleInstance.getModifiers().stream()
            .filter(mod -> mod.id().getPath().startsWith("genetics_"))
            .toList()
            .forEach(scaleInstance::removeModifier);
    }
}

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🔗 Related Pages

• Animal Genetics Engine
• Genetics API & Pedigree