Java tutorial
/** * This class was created by <Vazkii>. It's distributed as * part of the Botania Mod. Get the Source Code in github: * https://github.com/Vazkii/Botania * * Botania is Open Source and distributed under the * Botania License: http://botaniamod.net/license.php * * File Created @ [Nov 24, 2014, 5:58:22 PM (GMT)] */ package vazkii.botania.common.entity; import java.util.List; import javax.annotation.Nonnull; import com.google.common.base.Predicates; import net.minecraft.block.Block; import net.minecraft.block.BlockBush; import net.minecraft.block.BlockLeaves; import net.minecraft.entity.Entity; import net.minecraft.entity.EntityLivingBase; import net.minecraft.entity.monster.IMob; import net.minecraft.entity.player.EntityPlayer; import net.minecraft.entity.projectile.EntityThrowable; import net.minecraft.nbt.NBTTagCompound; import net.minecraft.network.datasync.DataParameter; import net.minecraft.network.datasync.DataSerializers; import net.minecraft.network.datasync.EntityDataManager; import net.minecraft.util.DamageSource; import net.minecraft.util.math.AxisAlignedBB; import net.minecraft.util.math.RayTraceResult; import net.minecraft.world.World; import net.minecraftforge.fml.relauncher.ReflectionHelper; import vazkii.botania.common.Botania; import vazkii.botania.common.core.helper.Vector3; import vazkii.botania.common.lib.LibObfuscation; public class EntityMagicMissile extends EntityThrowable { private static final String TAG_TIME = "time"; private static final DataParameter<Boolean> EVIL = EntityDataManager.createKey(EntityMagicMissile.class, DataSerializers.BOOLEAN); private static final DataParameter<Integer> TARGET = EntityDataManager.createKey(EntityMagicMissile.class, DataSerializers.VARINT); double lockX, lockY = -1, lockZ; int time = 0; public EntityMagicMissile(World world) { super(world); setSize(0F, 0F); } public EntityMagicMissile(EntityLivingBase thrower, boolean evil) { this(thrower.worldObj); ReflectionHelper.setPrivateValue(EntityThrowable.class, this, thrower, LibObfuscation.THROWER); setEvil(evil); } @Override protected void entityInit() { dataManager.register(EVIL, false); dataManager.register(TARGET, 0); } public void setEvil(boolean evil) { dataManager.set(EVIL, evil); } public boolean isEvil() { return dataManager.get(EVIL); } public void setTarget(EntityLivingBase e) { dataManager.set(TARGET, e == null ? -1 : e.getEntityId()); } public EntityLivingBase getTargetEntity() { int id = dataManager.get(TARGET); Entity e = worldObj.getEntityByID(id); if (e != null && e instanceof EntityLivingBase) return (EntityLivingBase) e; return null; } @Override public void onUpdate() { double lastTickPosX = this.lastTickPosX; double lastTickPosY = this.lastTickPosY; double lastTickPosZ = this.lastTickPosZ; super.onUpdate(); if (!worldObj.isRemote && (!getTarget() || time > 40)) { setDead(); return; } boolean evil = isEvil(); Vector3 thisVec = Vector3.fromEntityCenter(this); Vector3 oldPos = new Vector3(lastTickPosX, lastTickPosY, lastTickPosZ); Vector3 diff = thisVec.subtract(oldPos); Vector3 step = diff.normalize().multiply(0.05); int steps = (int) (diff.mag() / step.mag()); Vector3 particlePos = oldPos; Botania.proxy.setSparkleFXCorrupt(evil); for (int i = 0; i < steps; i++) { Botania.proxy.sparkleFX(particlePos.x, particlePos.y, particlePos.z, 1F, evil ? 0F : 0.4F, 1F, 0.8F, 2); if (worldObj.rand.nextInt(steps) <= 1) Botania.proxy.sparkleFX(particlePos.x + (Math.random() - 0.5) * 0.4, particlePos.y + (Math.random() - 0.5) * 0.4, particlePos.z + (Math.random() - 0.5) * 0.4, 1F, evil ? 0F : 0.4F, 1F, 0.8F, 2); particlePos = particlePos.add(step); } Botania.proxy.setSparkleFXCorrupt(false); EntityLivingBase target = getTargetEntity(); if (target != null) { if (lockY == -1) { lockX = target.posX; lockY = target.posY; lockZ = target.posZ; } Vector3 targetVec = evil ? new Vector3(lockX, lockY, lockZ) : Vector3.fromEntityCenter(target); Vector3 diffVec = targetVec.subtract(thisVec); Vector3 motionVec = diffVec.normalize().multiply(evil ? 0.5 : 0.6); motionX = motionVec.x; motionY = motionVec.y; if (time < 10) motionY = Math.abs(motionY); motionZ = motionVec.z; List<EntityLivingBase> targetList = worldObj.getEntitiesWithinAABB(EntityLivingBase.class, new AxisAlignedBB(posX - 0.5, posY - 0.5, posZ - 0.5, posX + 0.5, posY + 0.5, posZ + 0.5)); if (targetList.contains(target) && target != null) { EntityLivingBase thrower = getThrower(); if (thrower != null) { EntityPlayer player = thrower instanceof EntityPlayer ? (EntityPlayer) thrower : null; target.attackEntityFrom(player == null ? DamageSource.causeMobDamage(thrower) : DamageSource.causePlayerDamage(player), evil ? 12 : 7); } else target.attackEntityFrom(DamageSource.generic, evil ? 12 : 7); setDead(); } if (evil && diffVec.mag() < 1) setDead(); } time++; } @Override public void writeEntityToNBT(NBTTagCompound cmp) { super.writeEntityToNBT(cmp); cmp.setInteger(TAG_TIME, time); } @Override public void readEntityFromNBT(NBTTagCompound cmp) { super.readEntityFromNBT(cmp); time = cmp.getInteger(TAG_TIME); } public boolean getTarget() { EntityLivingBase target = getTargetEntity(); if (target != null && target.getHealth() > 0 && !target.isDead && worldObj.loadedEntityList.contains(target)) return true; if (target != null) setTarget(null); double range = 12; List entities = worldObj.getEntitiesWithinAABB( Entity.class, new AxisAlignedBB(posX - range, posY - range, posZ - range, posX + range, posY + range, posZ + range), Predicates.instanceOf(isEvil() ? EntityPlayer.class : IMob.class)); while (entities.size() > 0) { Entity e = (Entity) entities.get(worldObj.rand.nextInt(entities.size())); if (!(e instanceof EntityLivingBase) || e.isDead) { // Just in case... entities.remove(e); continue; } target = (EntityLivingBase) e; setTarget(target); break; } return target != null; } @Override protected void onImpact(@Nonnull RayTraceResult pos) { switch (pos.typeOfHit) { case BLOCK: { Block block = worldObj.getBlockState(pos.getBlockPos()).getBlock(); if (!(block instanceof BlockBush) && !(block instanceof BlockLeaves)) setDead(); break; } case ENTITY: { if (pos.entityHit == getTargetEntity()) setDead(); break; } default: { setDead(); break; } } } }