I have made an item which shoots my custom projectile all is good until i bring the velocity of the projectile to around 15 or higher.  At this point it begins to prefer aiming at 45 degree angles.  rather than where i am actually aiming.  I assume it has to do with how im calculating the motion of the projectile.  Does anyone know how i can fix this problem.

 

Spoiler

package com.drok.progressiveg.common.item;

import com.drok.progressiveg.GunMod;
import com.drok.progressiveg.entity.projectile.EntityLeadBullet;

import net.minecraft.entity.Entity;
import net.minecraft.entity.item.EntityEnderPearl;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.init.SoundEvents;
import net.minecraft.item.Item;
import net.minecraft.item.ItemStack;
import net.minecraft.stats.StatList;
import net.minecraft.util.ActionResult;
import net.minecraft.util.EnumActionResult;
import net.minecraft.util.EnumHand;
import net.minecraft.util.SoundCategory;
import net.minecraft.world.World;

public class ItemLeadGun extends Item {
	
	public Item ammo;
	public int damage;
	public int velocity;
	
	public ItemLeadGun(String name, Item ammo, int damage, int velocity) {
		this();
		this.ammo = ammo;
		this.damage = damage;
		this.velocity = velocity;
		
		this.setRegistryName(name);
		this.setUnlocalizedName(name);
		
	}
	
	public ItemLeadGun() {
		this.setCreativeTab(GunMod.TABGUNS);
		this.setMaxStackSize(1);
		
	}
	
	public ActionResult<ItemStack> onItemRightClick(World worldIn, EntityPlayer playerIn, EnumHand handIn)
    {
		ItemStack item = findAmmo(playerIn);
		
		if(!item.isEmpty()) {
			EntityLeadBullet bullet = new EntityLeadBullet(worldIn, playerIn, damage);
			bullet.setAim(playerIn, playerIn.rotationPitch, playerIn.rotationYaw, 0.0F, 20, 0);
			bullet.posX = playerIn.posX;
			bullet.posY = playerIn.posY + 1;
			bullet.posZ = playerIn.posZ;
			
			
			worldIn.spawnEntity(bullet);

			return new ActionResult<ItemStack>(EnumActionResult.SUCCESS, playerIn.getHeldItemMainhand());
		} else {
			return new ActionResult<ItemStack>(EnumActionResult.FAIL, playerIn.getHeldItemMainhand());
		}
    }
	
	 private ItemStack findAmmo(EntityPlayer player)
	 {
	        for(int i = 0; i < player.inventory.getSizeInventory(); i++) {
	        	ItemStack item = player.inventory.getStackInSlot(i);
	        	
	        	
	        	if(item != null) {
	        		if(item.getItem().getUnlocalizedName().equalsIgnoreCase(ammo.getUnlocalizedName())) {
	        			return item;
	        		}
	        	}
	        }
	        return ItemStack.EMPTY;
	 }
}

 

 

package com.drok.progressiveg.entity.projectile;

import com.drok.progressiveg.GunMod;

import net.minecraft.block.material.Material;
import net.minecraft.block.state.IBlockState;
import net.minecraft.entity.Entity;
import net.minecraft.entity.EntityLivingBase;
import net.minecraft.entity.IProjectile;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.entity.projectile.EntityArrow;
import net.minecraft.item.ItemStack;
import net.minecraft.nbt.NBTTagCompound;
import net.minecraft.util.DamageSource;
import net.minecraft.util.math.BlockPos;
import net.minecraft.util.math.MathHelper;
import net.minecraft.util.math.RayTraceResult;
import net.minecraft.util.math.Vec3d;
import net.minecraft.world.World;
import net.minecraftforge.fml.common.registry.IThrowableEntity;

public class EntityLeadBullet extends Entity implements IProjectile {

	public Entity owner;
	public int damage;
	
	public float speed() {
		float a = (float) Math.abs(this.motionX);
		float b = (float) Math.abs(this.motionY);;
		float c = (float) Math.abs(this.motionZ);;
		
		return (a + b + c) / 3;
	};
	
	public EntityLeadBullet(World worldIn) {
		this(worldIn, null, 0);
	}
	
	public EntityLeadBullet(World worldIn, Entity own, int dmg) {
		super(worldIn);
		
		owner = own;
		damage = dmg;
		
		this.setSize(0.5F, 0.5F);
		this.setNoGravity(false);
		this.setVelocity(0, 0, 50);
	}
	
	public void setAim(Entity entityThrower, float rotationPitchIn, float rotationYawIn, float pitchOffset, float velocity, float inaccuracy)
    {
        double f = -MathHelper.sin(rotationYawIn * 0.017453292F) * MathHelper.cos(rotationPitchIn * 0.017453292F);
        double f1 = -MathHelper.sin((rotationPitchIn + pitchOffset) * 0.017453292F);
        double f2 = MathHelper.cos(rotationYawIn * 0.017453292F) * MathHelper.cos(rotationPitchIn * 0.017453292F);
        this.setThrowableHeading((double)f, (double)f1, (double)f2, velocity, inaccuracy);
        this.motionX += entityThrower.motionX;
        this.motionZ += entityThrower.motionZ;

        if (!entityThrower.onGround)
        {
            this.motionY += entityThrower.motionY;
        }
    }
	
	@Override
	public void setVelocity(double x, double y, double z) {
		this.motionX = x;
        this.motionY = y;
        this.motionZ = z;
		
	}
	
	@Override
	public void onUpdate() {
		super.onUpdate();
		
		this.posX += this.motionX;
		this.posY += this.motionY;
   		this.posZ += this.motionZ;
   		Vec3d from = new Vec3d(this.posX, this.posY, this.posZ);
   		Vec3d to = new Vec3d(this.posX + this.motionX, this.posY + this.motionY, this.posZ + this.motionZ);
   		RayTraceResult raytraceresult = this.world.rayTraceBlocks(from, to, false, true, false);
   		
   		if(raytraceresult != null) {
   			this.onHit(raytraceresult);
   		}
   		
   		this.motionX *= 0.99;
   		this.motionY *= 0.99;
   		this.motionZ *= 0.99;
   		
   		this.motionY -= 0.05000000074505806D;
   		
		this.setPosition(this.posX, this.posY, this.posZ);
		this.doBlockCollisions();
	}
	
	protected void onHit(RayTraceResult result)
    {
		GunMod.log(result.getBlockPos().toString());
		
		Entity entity = result.entityHit;
		
		if(entity != null) {
			DamageSource damagesource = null;

            if (this.owner == null && this.owner instanceof EntityPlayer)
            {
                damagesource = DamageSource.causePlayerDamage((EntityPlayer) this.owner);
            }
            else if (this.owner == null && this.owner instanceof EntityLivingBase)
            {
                damagesource = DamageSource.causeMobDamage((EntityLivingBase) this.owner);
            } else {
            	GunMod.log("No Valid Bullet Owner!  Please contact the mod developer.");
            	return;
            }
            
            entity.attackEntityFrom(damagesource, this.damage);
			
		} else {
			BlockPos blkpos = result.getBlockPos();
			IBlockState blkst = this.world.getBlockState(blkpos);
			if(blkst.getMaterial() == Material.GLASS && speed() > 7) {
				world.setBlockToAir(blkpos);
				for(int x = -1; x < 2; x++) {
					for(int y = -1; y < 2; y++) {
						for(int z = -1; z < 2; z++) {
							BlockPos blkpos2 = blkpos;
							blkpos2 = blkpos2.add(x, y, z);
							IBlockState blkst2 = this.world.getBlockState(blkpos2);
							GunMod.log("1: " + blkpos + ", 2: " + blkpos2);
							if(blkst2.getMaterial() == Material.GLASS && GunMod.rand.nextBoolean()) {
								world.setBlockToAir(blkpos2);
								this.motionX *= 0.5f;
								this.motionY *= 0.5f;
								this.motionZ *= 0.5f;
							}
						}	
					}	
				}
			} else {
				this.setDead();
			}
			
		}
    }

	@Override
	public void setThrowableHeading(double x, double y, double z, float velocity, float inaccuracy)
    {
        float f = MathHelper.sqrt(x * x + y * y + z * z);
        x = x / (double)f;
        y = y / (double)f;
        z = z / (double)f;
        x = x + this.rand.nextGaussian() * 0.007499999832361937D * (double)inaccuracy;
        y = y + this.rand.nextGaussian() * 0.007499999832361937D * (double)inaccuracy;
        z = z + this.rand.nextGaussian() * 0.007499999832361937D * (double)inaccuracy;
        x = x * (double)velocity;
        y = y * (double)velocity;
        z = z * (double)velocity;
        this.motionX = x;
        this.motionY = y;
        this.motionZ = z;
        float f1 = MathHelper.sqrt(x * x + z * z);
        this.rotationYaw = (float)(MathHelper.atan2(x, z) * (180D / Math.PI));
        this.rotationPitch = (float)(MathHelper.atan2(y, (double)f1) * (180D / Math.PI));
        this.prevRotationYaw = this.rotationYaw;
        this.prevRotationPitch = this.rotationPitch;
        //this.ticksInGround = 0;
    }

	@Override
	protected void entityInit() {
		// TODO Auto-generated method stub
		
	}

	@Override
	protected void readEntityFromNBT(NBTTagCompound compound) {
		// TODO Auto-generated method stub
		
	}

	@Override
	protected void writeEntityToNBT(NBTTagCompound compound) {
		// TODO Auto-generated method stub
		
	}

}

 

 

Ok i have done some testing and it travels correctly when it comes to its position and collisions but visually it's incorrect.  Why could this be happening and is there a way to fix it?