001package net.minecraft.entity.ai;
002
003import net.minecraft.entity.Entity;
004import net.minecraft.entity.EntityLiving;
005import net.minecraft.util.MathHelper;
006
007public class EntityLookHelper
008{
009    private EntityLiving entity;
010
011    /**
012     * The amount of change that is made each update for an entity facing a direction.
013     */
014    private float deltaLookYaw;
015
016    /**
017     * The amount of change that is made each update for an entity facing a direction.
018     */
019    private float deltaLookPitch;
020
021    /** Whether or not the entity is trying to look at something. */
022    private boolean isLooking = false;
023    private double posX;
024    private double posY;
025    private double posZ;
026
027    public EntityLookHelper(EntityLiving par1EntityLiving)
028    {
029        this.entity = par1EntityLiving;
030    }
031
032    /**
033     * Sets position to look at using entity
034     */
035    public void setLookPositionWithEntity(Entity par1Entity, float par2, float par3)
036    {
037        this.posX = par1Entity.posX;
038
039        if (par1Entity instanceof EntityLiving)
040        {
041            this.posY = par1Entity.posY + (double)par1Entity.getEyeHeight();
042        }
043        else
044        {
045            this.posY = (par1Entity.boundingBox.minY + par1Entity.boundingBox.maxY) / 2.0D;
046        }
047
048        this.posZ = par1Entity.posZ;
049        this.deltaLookYaw = par2;
050        this.deltaLookPitch = par3;
051        this.isLooking = true;
052    }
053
054    /**
055     * Sets position to look at
056     */
057    public void setLookPosition(double par1, double par3, double par5, float par7, float par8)
058    {
059        this.posX = par1;
060        this.posY = par3;
061        this.posZ = par5;
062        this.deltaLookYaw = par7;
063        this.deltaLookPitch = par8;
064        this.isLooking = true;
065    }
066
067    /**
068     * Updates look
069     */
070    public void onUpdateLook()
071    {
072        this.entity.rotationPitch = 0.0F;
073
074        if (this.isLooking)
075        {
076            this.isLooking = false;
077            double var1 = this.posX - this.entity.posX;
078            double var3 = this.posY - (this.entity.posY + (double)this.entity.getEyeHeight());
079            double var5 = this.posZ - this.entity.posZ;
080            double var7 = (double)MathHelper.sqrt_double(var1 * var1 + var5 * var5);
081            float var9 = (float)(Math.atan2(var5, var1) * 180.0D / Math.PI) - 90.0F;
082            float var10 = (float)(-(Math.atan2(var3, var7) * 180.0D / Math.PI));
083            this.entity.rotationPitch = this.updateRotation(this.entity.rotationPitch, var10, this.deltaLookPitch);
084            this.entity.rotationYawHead = this.updateRotation(this.entity.rotationYawHead, var9, this.deltaLookYaw);
085        }
086        else
087        {
088            this.entity.rotationYawHead = this.updateRotation(this.entity.rotationYawHead, this.entity.renderYawOffset, 10.0F);
089        }
090
091        float var11 = MathHelper.wrapAngleTo180_float(this.entity.rotationYawHead - this.entity.renderYawOffset);
092
093        if (!this.entity.getNavigator().noPath())
094        {
095            if (var11 < -75.0F)
096            {
097                this.entity.rotationYawHead = this.entity.renderYawOffset - 75.0F;
098            }
099
100            if (var11 > 75.0F)
101            {
102                this.entity.rotationYawHead = this.entity.renderYawOffset + 75.0F;
103            }
104        }
105    }
106
107    private float updateRotation(float par1, float par2, float par3)
108    {
109        float var4 = MathHelper.wrapAngleTo180_float(par2 - par1);
110
111        if (var4 > par3)
112        {
113            var4 = par3;
114        }
115
116        if (var4 < -par3)
117        {
118            var4 = -par3;
119        }
120
121        return par1 + var4;
122    }
123}