From ab7b88d1a041083fe201fc9143dfd6bf03492e17 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Sun, 3 Aug 2014 15:07:49 +0200
Subject: [PATCH] Made robot afterimages declare themselves as air blocks and
 made robots ignore afterimages when moving, to avoid potential issues when
 for some reason they were not properly cleaned up (e.g. on chunk borders
 after world loads). Might help with #440.

---
 src/main/scala/li/cil/oc/common/block/Delegate.scala        | 2 ++
 src/main/scala/li/cil/oc/common/block/Delegator.scala       | 6 ++++++
 src/main/scala/li/cil/oc/common/block/RobotAfterimage.scala | 2 ++
 src/main/scala/li/cil/oc/common/tileentity/Robot.scala      | 2 +-
 4 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/main/scala/li/cil/oc/common/block/Delegate.scala b/src/main/scala/li/cil/oc/common/block/Delegate.scala
index 3f4899259..f31d973cd 100644
--- a/src/main/scala/li/cil/oc/common/block/Delegate.scala
+++ b/src/main/scala/li/cil/oc/common/block/Delegate.scala
@@ -50,6 +50,8 @@ trait Delegate {
 
   def explosionResistance(entity: Entity): Float = parent.getExplosionResistance(entity)
 
+  def isAir(world: World, x: Int, y: Int, z: Int) = false
+
   def isNormalCube(world: World, x: Int, y: Int, z: Int) = true
 
   def validRotations(world: World, x: Int, y: Int, z: Int) = validRotations_
diff --git a/src/main/scala/li/cil/oc/common/block/Delegator.scala b/src/main/scala/li/cil/oc/common/block/Delegator.scala
index 5a2d3971d..bf96b59d4 100644
--- a/src/main/scala/li/cil/oc/common/block/Delegator.scala
+++ b/src/main/scala/li/cil/oc/common/block/Delegator.scala
@@ -146,6 +146,12 @@ class Delegator[Child <: Delegate](id: Int) extends Block(id, Material.iron) {
       case _ => super.getExplosionResistance(entity, world, x, y, z, explosionX, explosionY, explosionZ)
     }
 
+  override def isAirBlock(world: World, x: Int, y: Int, z: Int) =
+    subBlock(world, x, y, z) match {
+      case Some(subBlock) => subBlock.isAir(world, x, y, z)
+      case _ => super.isAirBlock(world, x, y, z)
+    }
+
   override def isBlockNormalCube(world: World, x: Int, y: Int, z: Int) =
     subBlock(world.getBlockMetadata(x, y, z)) match {
       case Some(subBlock) => subBlock.isNormalCube(world, x, y, z)
diff --git a/src/main/scala/li/cil/oc/common/block/RobotAfterimage.scala b/src/main/scala/li/cil/oc/common/block/RobotAfterimage.scala
index 3aa35897d..d955f7595 100644
--- a/src/main/scala/li/cil/oc/common/block/RobotAfterimage.scala
+++ b/src/main/scala/li/cil/oc/common/block/RobotAfterimage.scala
@@ -39,6 +39,8 @@ class RobotAfterimage(val parent: SpecialDelegator) extends SpecialDelegate {
 
   override def opacity(world: World, x: Int, y: Int, z: Int) = 0
 
+  override def isAir(world: World, x: Int, y: Int, z: Int) = true
+
   override def isNormalCube(world: World, x: Int, y: Int, z: Int) = false
 
   override def isSolid(world: IBlockAccess, x: Int, y: Int, z: Int, side: ForgeDirection) = false
diff --git a/src/main/scala/li/cil/oc/common/tileentity/Robot.scala b/src/main/scala/li/cil/oc/common/tileentity/Robot.scala
index 455e036a5..18f635721 100644
--- a/src/main/scala/li/cil/oc/common/tileentity/Robot.scala
+++ b/src/main/scala/li/cil/oc/common/tileentity/Robot.scala
@@ -171,7 +171,7 @@ class Robot extends traits.Computer with traits.PowerInformation with api.machin
           // If we broke some replaceable block (like grass) play its break sound.
           if (blockId > 0) {
             val block = Block.blocksList(blockId)
-            if (block != null) {
+            if (block != null && !Delegator.subBlock(block, metadata).exists(_ == Blocks.robotAfterimage)) {
               if (FluidRegistry.lookupFluidForBlock(block) == null &&
                 !block.isInstanceOf[BlockFluidBase] &&
                 !block.isInstanceOf[BlockFlowing]) {