Code/net/minecraft/world/entity/ai/control/MoveControl.java

package net.minecraft.world.entity.ai.control;

import net.minecraft.core.BlockPos;
import net.minecraft.core.Direction;
import net.minecraft.tags.BlockTags;
import net.minecraft.util.Mth;
import net.minecraft.world.entity.Mob;
import net.minecraft.world.entity.ai.attributes.Attributes;
import net.minecraft.world.entity.ai.navigation.PathNavigation;
import net.minecraft.world.level.block.state.BlockState;
import net.minecraft.world.level.pathfinder.NodeEvaluator;
import net.minecraft.world.level.pathfinder.PathType;
import net.minecraft.world.phys.shapes.VoxelShape;

public class MoveControl implements Control {
    public static final float MIN_SPEED = 5.0E-4F;
    public static final float MIN_SPEED_SQR = 2.5000003E-7F;
    protected static final int MAX_TURN = 90;
    protected final Mob mob;
    protected double wantedX;
    protected double wantedY;
    protected double wantedZ;
    protected double speedModifier;
    protected float strafeForwards;
    protected float strafeRight;
    protected MoveControl.Operation operation = MoveControl.Operation.WAIT;

    public MoveControl(Mob p_24983_) {
        this.mob = p_24983_;
    }

    public boolean hasWanted() {
        return this.operation == MoveControl.Operation.MOVE_TO;
    }

    public double getSpeedModifier() {
        return this.speedModifier;
    }

    public void setWantedPosition(double p_24984_, double p_24985_, double p_24986_, double p_24987_) {
        this.wantedX = p_24984_;
        this.wantedY = p_24985_;
        this.wantedZ = p_24986_;
        this.speedModifier = p_24987_;
        if (this.operation != MoveControl.Operation.JUMPING) {
            this.operation = MoveControl.Operation.MOVE_TO;
        }
    }

    public void strafe(float p_24989_, float p_24990_) {
        this.operation = MoveControl.Operation.STRAFE;
        this.strafeForwards = p_24989_;
        this.strafeRight = p_24990_;
        this.speedModifier = 0.25;
    }

    public void tick() {
        if (this.operation == MoveControl.Operation.STRAFE) {
            float f = (float)this.mob.getAttributeValue(Attributes.MOVEMENT_SPEED);
            float f1 = (float)this.speedModifier * f;
            float f2 = this.strafeForwards;
            float f3 = this.strafeRight;
            float f4 = Mth.sqrt(f2 * f2 + f3 * f3);
            if (f4 < 1.0F) {
                f4 = 1.0F;
            }

            f4 = f1 / f4;
            f2 *= f4;
            f3 *= f4;
            float f5 = Mth.sin(this.mob.getYRot() * (float) (Math.PI / 180.0));
            float f6 = Mth.cos(this.mob.getYRot() * (float) (Math.PI / 180.0));
            float f7 = f2 * f6 - f3 * f5;
            float f8 = f3 * f6 + f2 * f5;
            if (!this.isWalkable(f7, f8)) {
                this.strafeForwards = 1.0F;
                this.strafeRight = 0.0F;
            }

            this.mob.setSpeed(f1);
            this.mob.setZza(this.strafeForwards);
            this.mob.setXxa(this.strafeRight);
            this.operation = MoveControl.Operation.WAIT;
        } else if (this.operation == MoveControl.Operation.MOVE_TO) {
            this.operation = MoveControl.Operation.WAIT;
            double d0 = this.wantedX - this.mob.getX();
            double d1 = this.wantedZ - this.mob.getZ();
            double d2 = this.wantedY - this.mob.getY();
            double d3 = d0 * d0 + d2 * d2 + d1 * d1;
            if (d3 < 2.5000003E-7F) {
                this.mob.setZza(0.0F);
                return;
            }

            float f9 = (float)(Mth.atan2(d1, d0) * 180.0F / (float)Math.PI) - 90.0F;
            this.mob.setYRot(this.rotlerp(this.mob.getYRot(), f9, 90.0F));
            this.mob.setSpeed((float)(this.speedModifier * this.mob.getAttributeValue(Attributes.MOVEMENT_SPEED)));
            BlockPos blockpos = this.mob.blockPosition();
            BlockState blockstate = this.mob.level().getBlockState(blockpos);
            VoxelShape voxelshape = blockstate.getCollisionShape(this.mob.level(), blockpos);
            if (d2 > this.mob.maxUpStep() && d0 * d0 + d1 * d1 < Math.max(1.0F, this.mob.getBbWidth())
                || !voxelshape.isEmpty()
                    && this.mob.getY() < voxelshape.max(Direction.Axis.Y) + blockpos.getY()
                    && !blockstate.is(BlockTags.DOORS)
                    && !blockstate.is(BlockTags.FENCES)) {
                this.mob.getJumpControl().jump();
                this.operation = MoveControl.Operation.JUMPING;
            }
        } else if (this.operation == MoveControl.Operation.JUMPING) {
            this.mob.setSpeed((float)(this.speedModifier * this.mob.getAttributeValue(Attributes.MOVEMENT_SPEED)));
            if (this.mob.onGround() || this.mob.isInLiquid() && this.mob.isAffectedByFluids()) {
                this.operation = MoveControl.Operation.WAIT;
            }
        } else {
            this.mob.setZza(0.0F);
        }
    }

    private boolean isWalkable(float p_24997_, float p_24998_) {
        PathNavigation pathnavigation = this.mob.getNavigation();
        if (pathnavigation != null) {
            NodeEvaluator nodeevaluator = pathnavigation.getNodeEvaluator();
            if (nodeevaluator != null
                && nodeevaluator.getPathType(
                        this.mob, BlockPos.containing(this.mob.getX() + p_24997_, this.mob.getBlockY(), this.mob.getZ() + p_24998_)
                    )
                    != PathType.WALKABLE) {
                return false;
            }
        }

        return true;
    }

    protected float rotlerp(float p_24992_, float p_24993_, float p_24994_) {
        float f = Mth.wrapDegrees(p_24993_ - p_24992_);
        if (f > p_24994_) {
            f = p_24994_;
        }

        if (f < -p_24994_) {
            f = -p_24994_;
        }

        float f1 = p_24992_ + f;
        if (f1 < 0.0F) {
            f1 += 360.0F;
        } else if (f1 > 360.0F) {
            f1 -= 360.0F;
        }

        return f1;
    }

    public double getWantedX() {
        return this.wantedX;
    }

    public double getWantedY() {
        return this.wantedY;
    }

    public double getWantedZ() {
        return this.wantedZ;
    }

    protected static enum Operation {
        WAIT,
        MOVE_TO,
        STRAFE,
        JUMPING;
    }
}