Code/net/minecraft/world/entity/boss/enderdragon/DragonFlightHistory.java

package net.minecraft.world.entity.boss.enderdragon;

import java.util.Arrays;
import net.minecraft.util.Mth;

public class DragonFlightHistory {
    public static final int LENGTH = 64;
    private static final int MASK = 63;
    private final DragonFlightHistory.Sample[] samples = new DragonFlightHistory.Sample[64];
    private int head = -1;

    public DragonFlightHistory() {
        Arrays.fill(this.samples, new DragonFlightHistory.Sample(0.0, 0.0F));
    }

    public void copyFrom(DragonFlightHistory p_366507_) {
        System.arraycopy(p_366507_.samples, 0, this.samples, 0, 64);
        this.head = p_366507_.head;
    }

    public void record(double p_362558_, float p_366669_) {
        DragonFlightHistory.Sample dragonflighthistory$sample = new DragonFlightHistory.Sample(p_362558_, p_366669_);
        if (this.head < 0) {
            Arrays.fill(this.samples, dragonflighthistory$sample);
        }

        if (++this.head == 64) {
            this.head = 0;
        }

        this.samples[this.head] = dragonflighthistory$sample;
    }

    public DragonFlightHistory.Sample get(int p_365431_) {
        return this.samples[this.head - p_365431_ & 63];
    }

    public DragonFlightHistory.Sample get(int p_369995_, float p_366809_) {
        DragonFlightHistory.Sample dragonflighthistory$sample = this.get(p_369995_);
        DragonFlightHistory.Sample dragonflighthistory$sample1 = this.get(p_369995_ + 1);
        return new DragonFlightHistory.Sample(
            Mth.lerp(p_366809_, dragonflighthistory$sample1.y, dragonflighthistory$sample.y),
            Mth.rotLerp(p_366809_, dragonflighthistory$sample1.yRot, dragonflighthistory$sample.yRot)
        );
    }

    public record Sample(double y, float yRot) {
    }
}