Piston upgrade. Seems to work. For the most part.

src/main/resources/application.conf

@@ -636,6 +636,9 @@ opencomputers {
           # The amount of energy the chunkloader upgrade draws per tick while
           # it is enabled, i.e. actually loading a chunk.
           chunkloaderCost: 0.06
+
+          # The amount of energy pushing blocks with the piston upgrade costs.
+          pistonPush: 20
       }
 
       # Power values for different power systems.

src/main/resources/assets/opencomputers/lang/de_DE.lang

@@ -100,7 +100,8 @@ oc:item.UpgradeExperience.name=Erfahrungs-Upgrade
 oc:item.UpgradeGenerator.name=Generator-Upgrade
 oc:item.UpgradeInventory.name=Inventar-Upgrade
 oc:item.UpgradeInventoryController.name=Inventarbedienungs-Upgrade
-oc:item.UpgradeNavigation.name=Navigationsupgrade
+oc:item.UpgradeNavigation.name=Navigations-Upgrade
+oc:item.UpgradePiston.name=Kolben-Upgrade
 oc:item.UpgradeSign.name=Schild-I/O-Upgrade
 oc:item.UpgradeSolarGenerator.name=Solargenerator-Upgrade
 oc:item.UpgradeTractorBeam.name=Traktorstrahl-Upgrade
@@ -257,6 +258,7 @@ oc:tooltip.UpgradeGenerator=Kann verwendet werden, um unterwegs Energie aus Bren
 oc:tooltip.UpgradeInventory=Dieses Upgrade gibt Robotern ein internes Inventar. Ohne ein solches Upgrade können Roboter keine Gegenstände verwahren.
 oc:tooltip.UpgradeInventoryController=Dieses Upgrade erlaubt es dem Roboter, präziser mit externen Inventaren zu interagieren, und erlaubt es ihm, das angelegte Werkzeug mit einem Gegenstand in seinem Inventar auszutauschen.
 oc:tooltip.UpgradeNavigation=Erlaubt es Robotern, ihre Position und Ausrichtung zu bestimmen. Die Position ist relativ zur Mitte der Karte, die in diesem Upgrade verbaut wurde.
+oc:tooltip.UpgradePiston=Dieses Upgrade erlaubt es zu drängeln. Es macht es möglich Blöcke zu verschieben, ähnlich dem Kolben. Es kann jedoch §lkeine§7 Entities bewegen.
 oc:tooltip.UpgradeSign=Erlaubt das Lesen und Schreiben von Text auf Schildern.
 oc:tooltip.UpgradeSolarGenerator=Kann verwendet werden, um unterwegs Energie aus Sonnenlicht zu generieren. Benötigt eine ungehinderte Sicht zum Himmel über dem Roboter. Generiert Energie mit %s%% der Geschwindigkeit eines Stirlingmotors.
 oc:tooltip.UpgradeTractorBeam=Stattet den Roboter mit unglaublich fortschrittlicher Technologie - Kosename: "Gegenstandsmagnet" - aus. Erlaubt es dem Roboter, Gegenstände, innerhalb von 3 Blöcken um sich herum, einzusammeln.

src/main/resources/assets/opencomputers/lang/en_US.lang

@@ -101,6 +101,7 @@ oc:item.UpgradeGenerator.name=Generator Upgrade
 oc:item.UpgradeInventory.name=Inventory Upgrade
 oc:item.UpgradeInventoryController.name=Inventory Controller Upgrade
 oc:item.UpgradeNavigation.name=Navigation Upgrade
+oc:item.UpgradePiston.name=Piston Upgrade
 oc:item.UpgradeSign.name=Sign I/O Upgrade
 oc:item.UpgradeSolarGenerator.name=Solar Generator Upgrade
 oc:item.UpgradeTractorBeam.name=Tractor Beam Upgrade
@@ -257,6 +258,7 @@ oc:tooltip.UpgradeGenerator=Can be used to generate energy from fuel on the go.
 oc:tooltip.UpgradeInventory=This upgrade provides inventory space to the robot. Without one of these, robots will not be able to store items internally.
 oc:tooltip.UpgradeInventoryController=This upgrade allows the robot more control in how it interacts with external inventories, and allows it to swap its equipped tool with an item in its inventory.
 oc:tooltip.UpgradeNavigation=Can be used to determine the position and orientation of the robot. The position is relative to the center of the map that was used to craft this upgrade.
+oc:tooltip.UpgradePiston=This upgrade is very pushy. It allows moving blocks, similar to when using a piston. It does §lnot§7 move entities, however.
 oc:tooltip.UpgradeSign=Allows reading text on and writing text to signs.
 oc:tooltip.UpgradeSolarGenerator=Can be used to generate energy from sunlight on the go. Requires a clear line of sight to the sky above the robot. Generates energy at %s%% of the speed of a Stirling Engine.
 oc:tooltip.UpgradeTractorBeam=Equips the robot with extremely advanced technology, nicknamed the "Item Magnet". Allows it to pick up items anywhere within 3 blocks of its location.

src/main/resources/assets/opencomputers/recipes/default.recipes

@@ -176,6 +176,11 @@ navigationUpgrade {
           ["oc:circuitChip2", {item=map, subID=any}, "oc:circuitChip2"]
           [ingotGold, potion, ingotGold]]
 }
+pistonUpgrade {
+  input: [[ingotIron, craftingPiston, ingotIron]
+          [stickWood, "oc:circuitChip1", stickWood]
+          [ingotIron, "oc:materialCircuitBoardPrinted", ingotIron]]
+}
 signUpgrade {
   input: [[ingotIron, dyeBlack, ingotIron]
           ["oc:circuitChip1", stickWood, "oc:circuitChip1"]

src/main/scala/li/cil/oc/Items.scala

@@ -260,5 +260,8 @@ object Items extends ItemAPI {
 
     // 1.3.?
     registerItem(new item.TabletCase(multi), "tabletCase")
+
+    // 1.3.5
+    Recipes.addItem(new item.UpgradePiston(multi), "pistonUpgrade", "oc:pistonUpgrade")
   }
 }

src/main/scala/li/cil/oc/Settings.scala

@@ -171,6 +171,7 @@ class Settings(config: Config) {
   val robotComplexityCost = config.getDouble("power.cost.robotAssemblyComplexity") max 0
   val disassemblerItemCost = config.getDouble("power.cost.disassemblerPerItem") max 0
   val chunkloaderCost = config.getDouble("power.cost.chunkloaderCost") max 0
+  val pistonCost = config.getDouble("power.cost.pistonPush") max 0
 
   // power.value
   private val valueBuildCraft = config.getDouble("power.value.BuildCraft")

src/main/scala/li/cil/oc/common/Proxy.scala

@@ -95,6 +95,7 @@ class Proxy {
     api.Driver.add(driver.item.UpgradeInventory)
     api.Driver.add(driver.item.UpgradeInventoryController)
     api.Driver.add(driver.item.UpgradeNavigation)
+    api.Driver.add(driver.item.UpgradePiston)
     api.Driver.add(driver.item.UpgradeSign)
     api.Driver.add(driver.item.UpgradeSolarGenerator)
     api.Driver.add(driver.item.UpgradeTractorBeam)

src/main/scala/li/cil/oc/common/item/UpgradePiston.scala

@@ -0,0 +1,3 @@
+package li.cil.oc.common.item
+
+class UpgradePiston(val parent: Delegator) extends Delegate with ItemTier

src/main/scala/li/cil/oc/server/component/UpgradePiston.scala

@@ -0,0 +1,32 @@
+package li.cil.oc.server.component
+
+import cpw.mods.fml.relauncher.ReflectionHelper
+import li.cil.oc.Settings
+import li.cil.oc.api.driver.Container
+import li.cil.oc.api.network.{Arguments, Callback, Context, Visibility}
+import li.cil.oc.api.{Network, Rotatable}
+import li.cil.oc.common.component
+import net.minecraft.block.{Block, BlockPistonBase}
+import net.minecraft.world.World
+
+class UpgradePiston(val container: Rotatable with Container) extends component.ManagedComponent {
+  val node = Network.newNode(this, Visibility.Network).
+    withComponent("piston").
+    withConnector().
+    create()
+
+  private lazy val tryExtend = ReflectionHelper.findMethod(classOf[BlockPistonBase], null, Array("tryExtend", "func_72115_j", "f"), classOf[World], classOf[Int], classOf[Int], classOf[Int], classOf[Int])
+
+  @Callback(doc = """function(side:number):boolean -- Tries to push the block in front of the container of the upgrade.""")
+  def push(context: Context, args: Arguments): Array[AnyRef] = {
+    val (x, y, z) = (math.floor(container.xPosition).toInt, math.floor(container.yPosition).toInt, math.floor(container.zPosition).toInt)
+    val (bx, by, bz) = (x + container.facing.offsetX, y + container.facing.offsetY, z + container.facing.offsetZ)
+    if (!container.world.isAirBlock(bx, by, bz) && node.tryChangeBuffer(-Settings.get.pistonCost) && tryExtend.invoke(Block.pistonBase, container.world, x.underlying(), y.underlying(), z.underlying(), container.facing.ordinal.underlying()).asInstanceOf[Boolean]) {
+      container.world.setBlockToAir(bx, by, bz)
+      container.world.playSoundEffect(container.xPosition, container.yPosition, container.zPosition, "tile.piston.out", 0.5f, container.world.rand.nextFloat() * 0.25f + 0.6f)
+      context.pause(0.5)
+      result(true)
+    }
+    else result(false)
+  }
+}

src/main/scala/li/cil/oc/server/component/machine/luac/ComputerAPI.scala

@@ -1,6 +1,5 @@
 package li.cil.oc.server.component.machine.luac
 
-import com.naef.jnlua.LuaState
 import li.cil.oc.Settings
 import li.cil.oc.api.network.Connector
 import li.cil.oc.server.component.machine.NativeLuaArchitecture

src/main/scala/li/cil/oc/server/driver/item/UpgradePiston.scala

@@ -0,0 +1,18 @@
+package li.cil.oc.server.driver.item
+
+import li.cil.oc.api
+import li.cil.oc.api.Rotatable
+import li.cil.oc.api.driver.{Container, Slot}
+import li.cil.oc.server.component
+import net.minecraft.item.ItemStack
+
+object UpgradePiston extends Item {
+  override def worksWith(stack: ItemStack) = isOneOf(stack, api.Items.get("pistonUpgrade"))
+
+  override def createEnvironment(stack: ItemStack, container: Container) = container match {
+    case rotatable: Rotatable with Container => new component.UpgradePiston(rotatable)
+    case _ => null
+  }
+
+  override def slot(stack: ItemStack) = Slot.Upgrade
+}