Paper/nms-patches/EntityMinecartAbstract.patch

--- a/net/minecraft/server/EntityMinecartAbstract.java
+++ b/net/minecraft/server/EntityMinecartAbstract.java
@@ -4,6 +4,15 @@
 import java.util.Iterator;
 import java.util.Map;
 
+// CraftBukkit start
+import org.bukkit.Location;
+import org.bukkit.entity.Vehicle;
+import org.bukkit.event.vehicle.VehicleDamageEvent;
+import org.bukkit.event.vehicle.VehicleDestroyEvent;
+import org.bukkit.event.vehicle.VehicleEntityCollisionEvent;
+import org.bukkit.util.Vector;
+// CraftBukkit end
+
 public abstract class EntityMinecartAbstract extends Entity implements INamableTileEntity {
 
     private boolean a;
@@ -16,6 +25,17 @@
     private double h;
     private double i;
 
+    // CraftBukkit start
+    public boolean slowWhenEmpty = true;
+    private double derailedX = 0.5;
+    private double derailedY = 0.5;
+    private double derailedZ = 0.5;
+    private double flyingX = 0.95;
+    private double flyingY = 0.95;
+    private double flyingZ = 0.95;
+    public double maxSpeed = 0.4D;
+    // CraftBukkit end
+
     public EntityMinecartAbstract(World world) {
         super(world);
         this.k = true;
@@ -81,6 +101,8 @@
         this.lastX = d0;
         this.lastY = d1;
         this.lastZ = d2;
+
+        this.world.getServer().getPluginManager().callEvent(new org.bukkit.event.vehicle.VehicleCreateEvent((Vehicle) this.getBukkitEntity())); // CraftBukkit
     }
 
     public double an() {
@@ -92,6 +114,19 @@
             if (this.isInvulnerable(damagesource)) {
                 return false;
             } else {
+                // CraftBukkit start - fire VehicleDamageEvent
+                Vehicle vehicle = (Vehicle) this.getBukkitEntity();
+                org.bukkit.entity.Entity passenger = (damagesource.getEntity() == null) ? null : damagesource.getEntity().getBukkitEntity();
+
+                VehicleDamageEvent event = new VehicleDamageEvent(vehicle, passenger, f);
+                this.world.getServer().getPluginManager().callEvent(event);
+
+                if (event.isCancelled()) {
+                    return true;
+                }
+
+                f = (float) event.getDamage();
+                // CraftBukkit end
                 this.k(-this.r());
                 this.j(10);
                 this.ac();
@@ -99,6 +134,15 @@
                 boolean flag = damagesource.getEntity() instanceof EntityHuman && ((EntityHuman) damagesource.getEntity()).abilities.canInstantlyBuild;
 
                 if (flag || this.getDamage() > 40.0F) {
+                    // CraftBukkit start
+                    VehicleDestroyEvent destroyEvent = new VehicleDestroyEvent(vehicle, passenger);
+                    this.world.getServer().getPluginManager().callEvent(destroyEvent);
+
+                    if (destroyEvent.isCancelled()) {
+                        this.setDamage(40); // Maximize damage so this doesn't get triggered again right away
+                        return true;
+                    }
+                    // CraftBukkit end
                     if (this.passenger != null) {
                         this.passenger.mount((Entity) null);
                     }
@@ -140,6 +184,14 @@
     }
 
     public void t_() {
+        // CraftBukkit start
+        double prevX = this.locX;
+        double prevY = this.locY;
+        double prevZ = this.locZ;
+        float prevYaw = this.yaw;
+        float prevPitch = this.pitch;
+        // CraftBukkit end
+        
         if (this.getType() > 0) {
             this.j(this.getType() - 1);
         }
@@ -160,7 +212,7 @@
 
             i = this.L();
             if (this.ak) {
-                if (minecraftserver.getAllowNether()) {
+                if (true || minecraftserver.getAllowNether()) { // CraftBukkit - multi-world should still allow teleport even if default vanilla nether disabled
                     if (this.vehicle == null && this.al++ >= i) {
                         this.al = i;
                         this.portalCooldown = this.aq();
@@ -257,6 +309,20 @@
             }
 
             this.setYawPitch(this.yaw, this.pitch);
+
+            // CraftBukkit start
+            org.bukkit.World bworld = this.world.getWorld();
+            Location from = new Location(bworld, prevX, prevY, prevZ, prevYaw, prevPitch);
+            Location to = new Location(bworld, this.locX, this.locY, this.locZ, this.yaw, this.pitch);
+            Vehicle vehicle = (Vehicle) this.getBukkitEntity();
+
+            this.world.getServer().getPluginManager().callEvent(new org.bukkit.event.vehicle.VehicleUpdateEvent(vehicle));
+
+            if (!from.equals(to)) {
+                this.world.getServer().getPluginManager().callEvent(new org.bukkit.event.vehicle.VehicleMoveEvent(vehicle, from, to));
+            }
+            // CraftBukkit end
+
             Iterator iterator = this.world.getEntities(this, this.getBoundingBox().grow(0.20000000298023224D, 0.0D, 0.20000000298023224D)).iterator();
 
             while (iterator.hasNext()) {
@@ -280,7 +346,7 @@
     }
 
     protected double m() {
-        return 0.4D;
+        return this.maxSpeed; // CraftBukkit
     }
 
     public void a(int i, int j, int k, boolean flag) {}
@@ -291,16 +357,20 @@
         this.motX = MathHelper.a(this.motX, -d0, d0);
         this.motZ = MathHelper.a(this.motZ, -d0, d0);
         if (this.onGround) {
-            this.motX *= 0.5D;
-            this.motY *= 0.5D;
-            this.motZ *= 0.5D;
+            // CraftBukkit start - replace magic numbers with our variables
+            this.motX *= this.derailedX;
+            this.motY *= this.derailedY;
+            this.motZ *= this.derailedZ;
+            // CraftBukkit end
         }
 
         this.move(this.motX, this.motY, this.motZ);
         if (!this.onGround) {
-            this.motX *= 0.949999988079071D;
-            this.motY *= 0.949999988079071D;
-            this.motZ *= 0.949999988079071D;
+            // CraftBukkit start - replace magic numbers with our variables
+            this.motX *= this.flyingX;
+            this.motY *= this.flyingY;
+            this.motZ *= this.flyingZ;
+            // CraftBukkit end
         }
 
     }
@@ -488,7 +558,7 @@
     }
 
     protected void o() {
-        if (this.passenger != null) {
+        if (this.passenger != null || !this.slowWhenEmpty) { // CraftBukkit - add !this.slowWhenEmpty
             this.motX *= 0.996999979019165D;
             this.motY *= 0.0D;
             this.motZ *= 0.996999979019165D;
@@ -616,6 +686,17 @@
         if (!this.world.isClientSide) {
             if (!entity.noclip && !this.noclip) {
                 if (entity != this.passenger) {
+                    // CraftBukkit start
+                    Vehicle vehicle = (Vehicle) this.getBukkitEntity();
+                    org.bukkit.entity.Entity hitEntity = (entity == null) ? null : entity.getBukkitEntity();
+
+                    VehicleEntityCollisionEvent collisionEvent = new VehicleEntityCollisionEvent(vehicle, hitEntity);
+                    this.world.getServer().getPluginManager().callEvent(collisionEvent);
+
+                    if (collisionEvent.isCancelled()) {
+                        return;
+                    }
+                    // CraftBukkit end
                     if (entity instanceof EntityLiving && !(entity instanceof EntityHuman) && !(entity instanceof EntityIronGolem) && this.s() == EntityMinecartAbstract.EnumMinecartType.RIDEABLE && this.motX * this.motX + this.motZ * this.motZ > 0.01D && this.passenger == null && entity.vehicle == null) {
                         entity.mount(this);
                     }
@@ -624,7 +705,8 @@
                     double d1 = entity.locZ - this.locZ;
                     double d2 = d0 * d0 + d1 * d1;
 
-                    if (d2 >= 9.999999747378752E-5D) {
+                    // CraftBukkit - collision
+                    if (d2 >= 9.999999747378752E-5D && !collisionEvent.isCollisionCancelled()) {
                         d2 = (double) MathHelper.sqrt(d2);
                         d0 /= d2;
                         d1 /= d2;
@@ -891,4 +973,26 @@
 
         }
     }
+
+    // CraftBukkit start - Methods for getting and setting flying and derailed velocity modifiers
+    public Vector getFlyingVelocityMod() {
+        return new Vector(flyingX, flyingY, flyingZ);
+    }
+
+    public void setFlyingVelocityMod(Vector flying) {
+        flyingX = flying.getX();
+        flyingY = flying.getY();
+        flyingZ = flying.getZ();
+    }
+
+    public Vector getDerailedVelocityMod() {
+        return new Vector(derailedX, derailedY, derailedZ);
+    }
+
+    public void setDerailedVelocityMod(Vector derailed) {
+        derailedX = derailed.getX();
+        derailedY = derailed.getY();
+        derailedZ = derailed.getZ();
+    }
+    // CraftBukkit end
 }