more train coupling stuff

src/main/java/com/hbm/entity/train/EntityRailCarBase.java

@@ -1,5 +1,6 @@
 package com.hbm.entity.train;
 
+import java.util.ArrayList;
 import java.util.List;
 
 import com.hbm.blocks.rail.IRailNTM;
@@ -93,6 +94,7 @@ public abstract class EntityRailCarBase extends Entity {
 					if(neighbor.getCoupledTo(closestNeighborCoupling) != null) continue;
 					this.couple(closestOwnCoupling, neighbor);
 					neighbor.couple(closestNeighborCoupling, this);
+					player.swingItem();
 					return true;
 				}
 			}
@@ -282,10 +284,14 @@ public abstract class EntityRailCarBase extends Entity {
 	public abstract TrackGauge getGauge();
 	/** Returns the length between the core and one of the bogies */
 	public abstract double getLengthSpan();
-	/* Returns a collision box, usually smaller than the entity's AABB for rendering, which is used for colliding trains */
+	/** Returns a collision box, usually smaller than the entity's AABB for rendering, which is used for colliding trains */
 	public AxisAlignedBB getCollisionBox() {
 		return this.boundingBox;
 	}
+	/** Returns a collision box used for block collisions when derailed */
+	@Override public AxisAlignedBB getBoundingBox() {
+		return this.boundingBox;
+	}
 	
 	/** Returns the "true" position of the train, i.e. the block it wants to snap to */
 	public BlockPos getCurentAnchorPos() {
@@ -417,6 +423,8 @@ public abstract class EntityRailCarBase extends Entity {
 		
 		if(dist <= 0) return null;
 		
+		if(coupling == TrainCoupling.BACK) dist *= -1;
+		
 		Vec3 rot = Vec3.createVectorHelper(0, 0, dist);
 		rot.rotateAroundY((float) (-this.rotationYaw * Math.PI / 180D));
 		rot.xCoord += this.renderX;
@@ -433,4 +441,11 @@ public abstract class EntityRailCarBase extends Entity {
 		if(coupling == TrainCoupling.FRONT) this.coupledFront = to;
 		if(coupling == TrainCoupling.BACK) this.coupledBack = to;
 	}
+	
+	public static class LogicalTrainUnit {
+		
+		List<EntityRailCarBase> trains = new ArrayList();
+		
+		//TBI
+	}
 }

src/main/java/com/hbm/entity/train/EntityRailCarRidable.java

@@ -129,7 +129,7 @@ public abstract class EntityRailCarRidable extends EntityRailCarCargo {
 		if(nearestSeat == -1) {
 			player.mountEntity(this);
 		} else {
-			SeatDummyEntity dummySeat = new SeatDummyEntity(worldObj, this);
+			SeatDummyEntity dummySeat = new SeatDummyEntity(worldObj, this, nearestSeat);
 			Vec3 passengerSeat = this.getPassengerSeats()[nearestSeat];
 			passengerSeat.rotateAroundY((float) (-this.rotationYaw * Math.PI / 180));
 			double x = renderX + passengerSeat.xCoord;
@@ -194,16 +194,17 @@ public abstract class EntityRailCarRidable extends EntityRailCarCargo {
 		private double trainX;
 		private double trainY;
 		private double trainZ;
-		public EntityRailCarBase train;
+		public EntityRailCarRidable train;
 
 		public SeatDummyEntity(World world) { super(world); this.setSize(0.5F, 0.1F);}
-		public SeatDummyEntity(World world, EntityRailCarBase train) {
+		public SeatDummyEntity(World world, EntityRailCarRidable train, int index) {
 			this(world);
 			this.train = train;
 			if(train != null) this.dataWatcher.updateObject(3, train.getEntityId());
+			this.dataWatcher.updateObject(4, index);
 		}
 		
-		@Override protected void entityInit() { this.dataWatcher.addObject(3, new Integer(0)); }
+		@Override protected void entityInit() { this.dataWatcher.addObject(3, new Integer(0)); this.dataWatcher.addObject(4, new Integer(0)); }
 		@Override protected void writeEntityToNBT(NBTTagCompound nbt) { }
 		@Override public boolean writeToNBTOptional(NBTTagCompound nbt) { return false; }
 		@Override public void readEntityFromNBT(NBTTagCompound nbt) { this.setDead(); }
@@ -238,7 +239,30 @@ public abstract class EntityRailCarRidable extends EntityRailCarCargo {
 		@Override
 		public void updateRiderPosition() {
 			if(this.riddenByEntity != null) {
-				this.riddenByEntity.setPosition(this.posX, this.posY + 1, this.posZ);
+				
+				if(train == null) {
+					int eid = this.dataWatcher.getWatchableObjectInt(3);
+					Entity entity = worldObj.getEntityByID(eid);
+					if(entity instanceof EntityRailCarRidable) {
+						train = (EntityRailCarRidable) entity;
+					}
+				}
+				
+				//fallback for when train is null
+				if(train == null) {
+					this.riddenByEntity.setPosition(posX, posY + 1, posZ);
+					return;
+				}
+				
+				//doing it like this instead of with the position directly removes any discrepancies caused by entity tick order
+				//mmhmhmhm silky smooth
+				int index = this.dataWatcher.getWatchableObjectInt(4);
+				Vec3 rot = this.train.getPassengerSeats()[index];
+				rot.rotateAroundY((float) (-train.rotationYaw * Math.PI / 180));
+				double x = train.renderX + rot.xCoord;
+				double y = train.renderY + rot.yCoord;
+				double z = train.renderZ + rot.zCoord;
+				this.riddenByEntity.setPosition(x, y, z);
 			}
 		}
 	}

src/main/java/com/hbm/entity/train/TrainCargoTram.java

@@ -51,11 +51,12 @@ public class TrainCargoTram extends EntityRailCarElectric implements IGUIProvide
 
 	@Override public TrackGauge getGauge() { return TrackGauge.STANDARD; }
 	@Override public double getLengthSpan() { return 1.5; }
-	@Override public Vec3 getRiderSeatPosition() { return Vec3.createVectorHelper(0.375, 2.25, 0.5); }
+	@Override public Vec3 getRiderSeatPosition() { return Vec3.createVectorHelper(0.375, 2.375, 0.5); }
 	@Override public boolean shouldRiderSit() { return false; }
 	@Override public int getSizeInventory() { return 29; }
 	@Override public String getInventoryName() { return this.hasCustomInventoryName() ? this.getEntityName() : "container.trainTram"; }
 	@Override public AxisAlignedBB getCollisionBox() { return AxisAlignedBB.getBoundingBox(renderX, renderY, renderZ, renderX, renderY + 1, renderZ).expand(4, 0, 4); }
+	@Override public double getCouplingDist(TrainCoupling coupling) { return coupling != null ? 2.75 : 0; }
 
 	@Override public int getMaxPower() { return this.getPowerConsumption() * 100; }
 	@Override public int getPowerConsumption() { return 10; }

src/main/java/com/hbm/entity/train/TrainCargoTramTrailer.java

@@ -2,6 +2,7 @@ package com.hbm.entity.train;
 
 import com.hbm.blocks.rail.IRailNTM.TrackGauge;
 
+import net.minecraft.util.AxisAlignedBB;
 import net.minecraft.util.DamageSource;
 import net.minecraft.util.Vec3;
 import net.minecraft.world.World;
@@ -28,6 +29,8 @@ public class TrainCargoTramTrailer extends EntityRailCarCargo {
 	@Override public double getLengthSpan() { return 1.5; }
 	@Override public int getSizeInventory() { return 29; }
 	@Override public String getInventoryName() { return this.hasCustomInventoryName() ? this.getEntityName() : "container.trainTramTrailer"; }
+	@Override public AxisAlignedBB getCollisionBox() { return AxisAlignedBB.getBoundingBox(renderX, renderY, renderZ, renderX, renderY + 1, renderZ).expand(4, 0, 4); }
+	@Override public double getCouplingDist(TrainCoupling coupling) { return coupling != null ? 2.75 : 0; }
 
 	@Override
 	public double getCurrentSpeed() {

src/main/java/com/hbm/items/special/ItemTrain.java

@@ -8,12 +8,14 @@ import com.hbm.entity.train.TrainCargoTram;
 import com.hbm.entity.train.TrainCargoTramTrailer;
 import com.hbm.items.ItemEnumMulti;
 import com.hbm.util.EnumUtil;
+import com.hbm.util.fauxpointtwelve.BlockPos;
 
 import net.minecraft.block.Block;
 import net.minecraft.creativetab.CreativeTabs;
 import net.minecraft.entity.player.EntityPlayer;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.EnumChatFormatting;
+import net.minecraft.util.Vec3;
 import net.minecraft.world.World;
 
 public class ItemTrain extends ItemEnumMulti {
@@ -74,7 +76,13 @@ public class ItemTrain extends ItemEnumMulti {
 			if(train != null && train.getGauge() == ((IRailNTM) b).getGauge(world, x, y, z)) {
 				if(!world.isRemote) {
 					train.setPosition(x + fx, y + fy, z + fz);
+					BlockPos anchor = train.getCurentAnchorPos();
 					train.rotationYaw = entity.rotationYaw;
+					Vec3 corePos = train.getRelPosAlongRail(anchor, 0);
+					train.setPosition(corePos.xCoord, corePos.yCoord, corePos.zCoord);
+					Vec3 frontPos = train.getRelPosAlongRail(anchor, train.getLengthSpan());
+					Vec3 backPos = train.getRelPosAlongRail(anchor, -train.getLengthSpan());
+					train.rotationYaw = train.generateYaw(frontPos, backPos);
 					world.spawnEntityInWorld(train);
 				}