From c5cb7287c2dd10fe4bbbf6257d77bc2dd8b7065e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Mon, 24 Feb 2014 22:52:35 +0100
Subject: [PATCH 01/12] simplified autocreate method; added nil check for timer
 cleanup

---
 .../lua/component/internet/bin/irc.lua        | 24 +++++++++----------
 1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
index ebba420c7..65e2bf9c3 100644
--- a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
+++ b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
@@ -41,12 +41,8 @@ end
 
 -- utility method for reply tracking tables.
 function autocreate(table, key)
-  local value = rawget(table, key)
-  if not value then
-    value = {}
-    rawset(table, key, value)
-  end
-  return value
+  table[key] = {}
+  return table[key]
 end
 
 -- extract nickname from identity.
@@ -172,22 +168,22 @@ local function handleCommand(prefix, command, args, message)
     print(message)
   elseif command == commands.RPL_WHOISUSER then
     local nick = args[2]:lower()
-    whois[nick].nick = nick
+    whois[nick].nick = args[2]
     whois[nick].user = args[3]
     whois[nick].host = args[4]
     whois[nick].realName = message
   elseif command == commands.RPL_WHOISSERVER then
-    local nick = args[2]
+    local nick = args[2]:lower()
     whois[nick].server = args[3]
     whois[nick].serverInfo = message
   elseif command == commands.RPL_WHOISOPERATOR then
-    local nick = args[2]
+    local nick = args[2]:lower()
     whois[nick].isOperator = true
   elseif command == commands.RPL_WHOISIDLE then
-    local nick = args[2]
+    local nick = args[2]:lower()
     whois[nick].idle = tonumber(args[3])
   elseif command == commands.RPL_ENDOFWHOIS then
-    local nick = args[2]
+    local nick = args[2]:lower()
     local info = whois[nick]
     print("Nick: " .. info.nick)
     print("User name: " .. info.user)
@@ -198,7 +194,7 @@ local function handleCommand(prefix, command, args, message)
     print("Idle for: " .. info.idle)
     whois[nick] = nil
   elseif command == commands.RPL_WHOISCHANNELS then
-    local nick = args[1]
+    local nick = args[2]:lower()
     whois[nick].channels = message
   elseif command == commands.RPL_CHANNELMODEIS then
     print("Channel mode for " .. args[1] .. ": " .. args[2] .. "(" .. args[3] .. ")")
@@ -368,7 +364,9 @@ if sock then
   sock:write("QUIT\r\n")
   sock:close()
 end
-event.cancel(timer)
+if timer then
+  event.cancel(timer)
+end
 
 if not result then
   error(reason, 0)

From cd490f7ae2c8f72b4b43b89e635dc2b7a8b4467a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Mon, 24 Feb 2014 22:58:24 +0100
Subject: [PATCH 02/12] dem spaces before brackets

---
 .../assets/opencomputers/lua/component/internet/bin/irc.lua   | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
index 65e2bf9c3..68961055f 100644
--- a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
+++ b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
@@ -189,7 +189,7 @@ local function handleCommand(prefix, command, args, message)
     print("User name: " .. info.user)
     print("Real name: " .. info.realName)
     print("Host: " .. info.host)
-    print("Server: " .. info.server .. "(" .. info.serverInfo .. ")")
+    print("Server: " .. info.server .. " (" .. info.serverInfo .. ")")
     print("Channels: " .. info.channels)
     print("Idle for: " .. info.idle)
     whois[nick] = nil
@@ -197,7 +197,7 @@ local function handleCommand(prefix, command, args, message)
     local nick = args[2]:lower()
     whois[nick].channels = message
   elseif command == commands.RPL_CHANNELMODEIS then
-    print("Channel mode for " .. args[1] .. ": " .. args[2] .. "(" .. args[3] .. ")")
+    print("Channel mode for " .. args[1] .. ": " .. args[2] .. " (" .. args[3] .. ")")
   elseif command == commands.RPL_NOTOPIC then
     print("No topic is set for " .. args[1] .. ".")
   elseif command == commands.RPL_TOPIC then

From 6116ef39428b67081f782a4b9eca5b17e5793fc9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Mon, 24 Feb 2014 23:26:56 +0100
Subject: [PATCH 03/12] not sending nil results from lua

---
 .../assets/opencomputers/lua/component/internet/bin/irc.lua     | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
index 68961055f..7675d2d90 100644
--- a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
+++ b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
@@ -338,7 +338,7 @@ local result, reason = pcall(function()
             print("Error: " .. tostring(reason))
           elseif type(reason) == "function" then
             callback = reason
-          else
+          elseif reason then
             line = tostring(reason)
           end
         end

From a9faf1c477a9978bed5acbc0ec60bd9dae5f2036 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Tue, 25 Feb 2014 00:06:11 +0100
Subject: [PATCH 04/12] nil checks for whois stuffs

---
 .../lua/component/internet/bin/irc.lua             | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
index 7675d2d90..d8749ecc1 100644
--- a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
+++ b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
@@ -185,13 +185,13 @@ local function handleCommand(prefix, command, args, message)
   elseif command == commands.RPL_ENDOFWHOIS then
     local nick = args[2]:lower()
     local info = whois[nick]
-    print("Nick: " .. info.nick)
-    print("User name: " .. info.user)
-    print("Real name: " .. info.realName)
-    print("Host: " .. info.host)
-    print("Server: " .. info.server .. " (" .. info.serverInfo .. ")")
-    print("Channels: " .. info.channels)
-    print("Idle for: " .. info.idle)
+    if info.nick then print("Nick: " .. info.nick) end
+    if info.user then print("User name: " .. info.user) end
+    if info.realName then print("Real name: " .. info.realName) end
+    if info.host then print("Host: " .. info.host) end
+    if info.server then print("Server: " .. info.server .. (info.serverInfo and (" (" .. info.serverInfo .. ")") or "")) end
+    if info.channels then print("Channels: " .. info.channels) end
+    if info.idle then print("Idle for: " .. info.idle) end
     whois[nick] = nil
   elseif command == commands.RPL_WHOISCHANNELS then
     local nick = args[2]:lower()

From 55a90f8b63671c9fb9b88a6f5ef521d126cd9d27 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Wed, 26 Feb 2014 00:34:01 +0100
Subject: [PATCH 05/12] fixed iron nugget recipe registration (stupid
 initialization order mix-up)

---
 src/main/java/li/cil/oc/Items.scala                        | 7 ++++---
 .../opencomputers/lua/component/internet/bin/irc.lua       | 4 +++-
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/src/main/java/li/cil/oc/Items.scala b/src/main/java/li/cil/oc/Items.scala
index 1535c50e5..257e09a22 100644
--- a/src/main/java/li/cil/oc/Items.scala
+++ b/src/main/java/li/cil/oc/Items.scala
@@ -95,9 +95,6 @@ object Items {
     upgradeGenerator = Recipes.addItem(new item.UpgradeGenerator(multi), "generatorUpgrade")
 
     ironNugget = new item.IronNugget(multi)
-    if (OreDictionary.getOres("nuggetIron").exists(ironNugget.createItemStack().isItemEqual)) {
-      Recipes.addItem(ironNugget, "nuggetIron")
-    }
 
     cuttingWire = Recipes.addItem(new item.CuttingWire(multi), "cuttingWire")
     acid = Recipes.addItem(new item.Acid(multi), "acid")
@@ -182,6 +179,10 @@ object Items {
     register("oc:craftingAcid", acid.createItemStack())
     register("oc:craftingGenerator", upgradeGenerator.createItemStack())
     register("oc:craftingSolarGenerator", upgradeSolarGenerator.createItemStack())
+
+    if (OreDictionary.getOres("nuggetIron").exists(ironNugget.createItemStack().isItemEqual)) {
+      Recipes.addItem(ironNugget, "nuggetIron")
+    }
   }
 
   def register(name: String, item: ItemStack) {
diff --git a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
index d8749ecc1..5eddd65bb 100644
--- a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
+++ b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
@@ -306,7 +306,9 @@ local result, reason = pcall(function()
       print("[" .. (target or "?") .. "] me: " .. line, true)
       if line:lower():sub(1, 5) == "/msg " then
         local user, message = line:sub(6):match("^(%S+) (.+)$")
-        message = text.trim(message)
+        if message then
+          message = text.trim(message)
+        end
         if not user or not message or message == "" then
           print("Invalid use of /msg. Usage: /msg nick|channel message.")
           line = ""

From 6f8bb90f2458fe67c94fc248cab1a24b84debb49 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Wed, 26 Feb 2014 01:13:53 +0100
Subject: [PATCH 06/12] fixed a bug in LuaJ's string.match. hopefully. closes
 #138

---
 src/main/required/org/luaj/vm3/lib/StringLib.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/required/org/luaj/vm3/lib/StringLib.java b/src/main/required/org/luaj/vm3/lib/StringLib.java
index 317d68920..afde5979b 100644
--- a/src/main/required/org/luaj/vm3/lib/StringLib.java
+++ b/src/main/required/org/luaj/vm3/lib/StringLib.java
@@ -1155,7 +1155,7 @@ public class StringLib extends TwoArgFunction {
 			if ( poff == plen || poff + 1 == plen ) {
 				error( "unbalanced pattern" );
 			}
-			if ( s.luaByte( soff ) != p.luaByte( poff ) )
+			if ( soff >= s.length() || s.luaByte( soff ) != p.luaByte( poff ) )
 				return -1;
 			else {
 				int b = p.luaByte( poff );

From 8072a50fd2a10f49700f11dc9de19be3f69a39ce Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Wed, 26 Feb 2014 17:02:34 +0100
Subject: [PATCH 07/12] basics for hologram projector

---
 src/main/java/li/cil/oc/Blocks.scala          |   5 +
 .../java/li/cil/oc/client/PacketHandler.scala |  13 ++
 src/main/java/li/cil/oc/client/Proxy.scala    |   1 +
 .../li/cil/oc/client/TexturePreloader.scala   |   1 +
 .../tileentity/HologramRenderer.scala         | 117 ++++++++++++++++++
 .../java/li/cil/oc/common/PacketType.scala    |   1 +
 .../li/cil/oc/common/block/Delegate.scala     |   4 +-
 .../li/cil/oc/common/block/Hologram.scala     |  33 +++++
 .../cil/oc/common/tileentity/Hologram.scala   |  93 ++++++++++++++
 .../java/li/cil/oc/server/PacketSender.scala  |  10 ++
 .../opencomputers/recipes/default.recipes     |   7 +-
 .../textures/blocks/hologram_effect.png       | Bin 0 -> 157 bytes
 12 files changed, 282 insertions(+), 3 deletions(-)
 create mode 100644 src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
 create mode 100644 src/main/java/li/cil/oc/common/block/Hologram.scala
 create mode 100644 src/main/java/li/cil/oc/common/tileentity/Hologram.scala
 create mode 100644 src/main/resources/assets/opencomputers/textures/blocks/hologram_effect.png

diff --git a/src/main/java/li/cil/oc/Blocks.scala b/src/main/java/li/cil/oc/Blocks.scala
index 7055dccce..3447b55f4 100644
--- a/src/main/java/li/cil/oc/Blocks.scala
+++ b/src/main/java/li/cil/oc/Blocks.scala
@@ -21,6 +21,7 @@ object Blocks {
   var case1, case2, case3: Case = _
   var diskDrive: DiskDrive = _
   var keyboard: Keyboard = _
+  var hologram: Hologram = _
   var powerConverter: PowerConverter = _
   var powerDistributor: PowerDistributor = _
   var redstone: Redstone = _
@@ -56,6 +57,7 @@ object Blocks {
     GameRegistry.registerTileEntity(classOf[tileentity.Charger], Settings.namespace + "charger")
     GameRegistry.registerTileEntity(classOf[tileentity.DiskDrive], Settings.namespace + "disk_drive")
     GameRegistry.registerTileEntity(classOf[tileentity.Keyboard], Settings.namespace + "keyboard")
+    GameRegistry.registerTileEntity(classOf[tileentity.Hologram], Settings.namespace + "hologram")
     GameRegistry.registerTileEntity(classOf[tileentity.PowerConverter], Settings.namespace + "power_converter")
     GameRegistry.registerTileEntity(classOf[tileentity.PowerDistributor], Settings.namespace + "power_distributor")
     GameRegistry.registerTileEntity(classOf[tileentity.Redstone], Settings.namespace + "redstone")
@@ -95,6 +97,9 @@ object Blocks {
     // v1.2.0
     serverRack = Recipes.addBlock(new Rack(blockSpecialWithRedstone), "rack")
 
+    // v1.2.2
+    hologram = Recipes.addBlock(new Hologram(blockSpecial), "hologram")
+
     register("oc:craftingCable", cable.createItemStack())
     register("oc:craftingCapacitor", capacitor.createItemStack())
     register("oc:craftingCaseTier1", case1.createItemStack())
diff --git a/src/main/java/li/cil/oc/client/PacketHandler.scala b/src/main/java/li/cil/oc/client/PacketHandler.scala
index f209814f0..47a7c593a 100644
--- a/src/main/java/li/cil/oc/client/PacketHandler.scala
+++ b/src/main/java/li/cil/oc/client/PacketHandler.scala
@@ -26,6 +26,7 @@ class PacketHandler extends CommonPacketHandler {
       case PacketType.ChargerState => onChargerState(p)
       case PacketType.ComputerState => onComputerState(p)
       case PacketType.ComputerUserList => onComputerUserList(p)
+      case PacketType.HologramSet => onHologramSet(p)
       case PacketType.PowerState => onPowerState(p)
       case PacketType.RedstoneState => onRedstoneState(p)
       case PacketType.RobotAnimateSwing => onRobotAnimateSwing(p)
@@ -100,6 +101,18 @@ class PacketHandler extends CommonPacketHandler {
       case _ => // Invalid packet.
     }
 
+  def onHologramSet(p: PacketParser) =
+    p.readTileEntity[Hologram]() match {
+      case Some(t) =>
+        val length = p.readInt()
+        val count = math.max(0, math.min(length, t.volume.length))
+        for (i <- 0 until count) {
+          t.volume(i) = p.readInt()
+        }
+        t.dirty = true
+      case _ => // Invalid packet.
+    }
+
   def onPowerState(p: PacketParser) =
     p.readTileEntity[PowerInformation]() match {
       case Some(t) =>
diff --git a/src/main/java/li/cil/oc/client/Proxy.scala b/src/main/java/li/cil/oc/client/Proxy.scala
index 6e1862247..c72df6230 100644
--- a/src/main/java/li/cil/oc/client/Proxy.scala
+++ b/src/main/java/li/cil/oc/client/Proxy.scala
@@ -28,6 +28,7 @@ private[oc] class Proxy extends CommonProxy {
 
     ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.Cable], CableRenderer)
     ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.Case], CaseRenderer)
+    ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.Hologram], HologramRenderer)
     ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.PowerDistributor], PowerDistributorRenderer)
     ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.Rack], RackRenderer)
     ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.RobotProxy], RobotRenderer)
diff --git a/src/main/java/li/cil/oc/client/TexturePreloader.scala b/src/main/java/li/cil/oc/client/TexturePreloader.scala
index e489214ba..b6e7bc80e 100644
--- a/src/main/java/li/cil/oc/client/TexturePreloader.scala
+++ b/src/main/java/li/cil/oc/client/TexturePreloader.scala
@@ -22,6 +22,7 @@ object TexturePreloader extends ResourceManagerReloadListener {
 
   val blockCable = new ResourceLocation(Settings.resourceDomain, "textures/blocks/cable.png")
   val blockCaseFrontOn = new ResourceLocation(Settings.resourceDomain, "textures/blocks/case_front_on.png")
+  val blockHologram = new ResourceLocation(Settings.resourceDomain, "textures/blocks/hologram_effect.png")
   val blockPowerDistributorOn = new ResourceLocation(Settings.resourceDomain, "textures/blocks/power_distributor_on.png")
   val blockRackFrontOn = new ResourceLocation(Settings.resourceDomain, "textures/blocks/rack_front_on.png")
   val blockRobot = new ResourceLocation(Settings.resourceDomain, "textures/blocks/robot.png")
diff --git a/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala b/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
new file mode 100644
index 000000000..c6a8ff2be
--- /dev/null
+++ b/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
@@ -0,0 +1,117 @@
+package li.cil.oc.client.renderer.tileentity
+
+import net.minecraft.client.renderer.tileentity.TileEntitySpecialRenderer
+import net.minecraft.tileentity.TileEntity
+import li.cil.oc.common.tileentity.Hologram
+import net.minecraft.client.renderer.Tessellator
+import org.lwjgl.opengl.GL11
+import li.cil.oc.util.RenderState
+import li.cil.oc.client.TexturePreloader
+import net.minecraftforge.client.MinecraftForgeClient
+
+object HologramRenderer extends TileEntitySpecialRenderer {
+  override def renderTileEntityAt(te: TileEntity, x: Double, y: Double, z: Double, f: Float) {
+    if (MinecraftForgeClient.getRenderPass != 0) return
+
+    val hologram = te.asInstanceOf[Hologram]
+
+    GL11.glPushAttrib(0xFFFFFFFF)
+    GL11.glDisable(GL11.GL_CULL_FACE)
+
+//    RenderState.disableLighting()
+    RenderState.makeItBlend()
+
+    GL11.glPushMatrix()
+    GL11.glTranslated(x - 1, y + 0.5, z - 1)
+
+    def isSolid(hx: Int, hy: Int, hz: Int) = {
+      hx >= 0 && hy >= 0 && hz >= 0 && hx < hologram.width && hy < hologram.height && hz < hologram.width &&
+        (hologram.volume(hx + hz * hologram.width) & (1 << hy)) != 0
+    }
+
+    bindTexture(TexturePreloader.blockHologram)
+    val t = Tessellator.instance
+    t.startDrawingQuads()
+    t.setColorRGBA_F(1, 1, 1, 0.7f)
+
+    val s = 1f / 16f
+    for (hx <- 0 until hologram.width) {
+      val wx = hx * s
+      for (hz <- 0 until hologram.width) {
+        val wz = hz * s
+        for (hy <- 0 until hologram.height) {
+          val wy = hy * s
+
+          if (isSolid(hx, hy, hz)) {
+            /*
+                  0---1
+                  | N |
+              0---3---2---1---0
+              | W | U | E | D |
+              5---6---7---4---5
+                  | S |
+                  5---4
+             */
+
+            // South
+            if (!isSolid(hx, hy, hz + 1)) {
+              t.setNormal(0, 0, 1)
+              t.addVertex(wx + s, wy + s, wz + s) // 5
+              t.addVertex(wx + 0, wy + s, wz + s) // 4
+              t.addVertex(wx + 0, wy + 0, wz + s) // 7
+              t.addVertex(wx + s, wy + 0, wz + s) // 6
+            }
+            // North
+            if (!isSolid(hx, hy, hz - 1)) {
+              t.setNormal(0, 0, -1)
+              t.addVertex(wx + s, wy + 0, wz + 0) // 3
+              t.addVertex(wx + 0, wy + 0, wz + 0) // 2
+              t.addVertex(wx + 0, wy + s, wz + 0) // 1
+              t.addVertex(wx + s, wy + s, wz + 0) // 0
+            }
+
+            // East
+            if (!isSolid(hx + 1, hy, hz)) {
+              t.setNormal(1, 0, 0)
+              t.addVertex(wx + s, wy + s, wz + s) // 5
+              t.addVertex(wx + s, wy + 0, wz + s) // 6
+              t.addVertex(wx + s, wy + 0, wz + 0) // 3
+              t.addVertex(wx + s, wy + s, wz + 0) // 0
+            }
+            // West
+            if (!isSolid(hx - 1, hy, hz)) {
+              t.setNormal(-1, 0, 0)
+              t.addVertex(wx + 0, wy + 0, wz + s) // 7
+              t.addVertex(wx + 0, wy + s, wz + s) // 4
+              t.addVertex(wx + 0, wy + s, wz + 0) // 1
+              t.addVertex(wx + 0, wy + 0, wz + 0) // 2
+            }
+
+            // Up
+            if (!isSolid(hx, hy + 1, hz)) {
+              t.setNormal(0, 1, 0)
+              t.addVertex(wx + s, wy + s, wz + 0) // 0
+              t.addVertex(wx + 0, wy + s, wz + 0) // 1
+              t.addVertex(wx + 0, wy + s, wz + s) // 4
+              t.addVertex(wx + s, wy + s, wz + s) // 5
+            }
+            // Down
+            if (!isSolid(hx, hy - 1, hz)) {
+              t.setNormal(0, -1, 0)
+              t.addVertex(wx + s, wy + 0, wz + s) // 6
+              t.addVertex(wx + 0, wy + 0, wz + s) // 7
+              t.addVertex(wx + 0, wy + 0, wz + 0) // 2
+              t.addVertex(wx + s, wy + 0, wz + 0) // 3
+            }
+
+          }
+        }
+      }
+    }
+
+    t.draw()
+
+    GL11.glPopMatrix()
+    GL11.glPopAttrib()
+  }
+}
diff --git a/src/main/java/li/cil/oc/common/PacketType.scala b/src/main/java/li/cil/oc/common/PacketType.scala
index eb98c912c..11013c6c1 100644
--- a/src/main/java/li/cil/oc/common/PacketType.scala
+++ b/src/main/java/li/cil/oc/common/PacketType.scala
@@ -8,6 +8,7 @@ object PacketType extends Enumeration {
   ChargerState,
   ComputerState,
   ComputerUserList,
+  HologramSet,
   PowerState,
   RedstoneState,
   RobotAnimateSwing,
diff --git a/src/main/java/li/cil/oc/common/block/Delegate.scala b/src/main/java/li/cil/oc/common/block/Delegate.scala
index 29defc757..626dc008f 100644
--- a/src/main/java/li/cil/oc/common/block/Delegate.scala
+++ b/src/main/java/li/cil/oc/common/block/Delegate.scala
@@ -41,11 +41,11 @@ trait Delegate {
 
   def canPlaceBlockOnSide(world: World, x: Int, y: Int, z: Int, side: ForgeDirection) = true
 
-  def bounds(world: World, x: Int, y: Int, z: Int) =
+  def bounds(world: IBlockAccess, x: Int, y: Int, z: Int) =
     AxisAlignedBB.getAABBPool.getAABB(0, 0, 0, 1, 1, 1)
 
   def updateBounds(world: IBlockAccess, x: Int, y: Int, z: Int) =
-    parent.setBlockBounds(0, 0, 0, 1, 1, 1)
+    parent.setBlockBounds(bounds(world, x, y, z))
 
   def intersect(world: World, x: Int, y: Int, z: Int, origin: Vec3, direction: Vec3) =
     parent.superCollisionRayTrace(world, x, y, z, origin, direction)
diff --git a/src/main/java/li/cil/oc/common/block/Hologram.scala b/src/main/java/li/cil/oc/common/block/Hologram.scala
new file mode 100644
index 000000000..9b926bb38
--- /dev/null
+++ b/src/main/java/li/cil/oc/common/block/Hologram.scala
@@ -0,0 +1,33 @@
+package li.cil.oc.common.block
+
+import java.util
+import li.cil.oc.common.tileentity
+import li.cil.oc.util.Tooltip
+import net.minecraft.entity.player.EntityPlayer
+import net.minecraft.item.{ItemStack, EnumRarity}
+import net.minecraft.world.{World, IBlockAccess}
+import net.minecraftforge.common.ForgeDirection
+import net.minecraft.util.AxisAlignedBB
+
+class Hologram(val parent: SpecialDelegator) extends SpecialDelegate {
+  val unlocalizedName = "Hologram"
+
+  override def rarity = EnumRarity.rare
+
+  override def tooltipLines(stack: ItemStack, player: EntityPlayer, tooltip: util.List[String], advanced: Boolean) {
+    tooltip.addAll(Tooltip.get(unlocalizedName))
+  }
+
+  override def luminance(world: IBlockAccess, x: Int, y: Int, z: Int) = 15
+
+  override def isSolid(world: IBlockAccess, x: Int, y: Int, z: Int, side: ForgeDirection) = side == ForgeDirection.DOWN
+
+  override def bounds(world: IBlockAccess, x: Int, y: Int, z: Int) =
+    AxisAlignedBB.getAABBPool.getAABB(0, 0, 0, 1, 0.2f, 1)
+
+  // ----------------------------------------------------------------------- //
+
+  override def hasTileEntity = true
+
+  override def createTileEntity(world: World) = Some(new tileentity.Hologram())
+}
diff --git a/src/main/java/li/cil/oc/common/tileentity/Hologram.scala b/src/main/java/li/cil/oc/common/tileentity/Hologram.scala
new file mode 100644
index 000000000..94dba39ce
--- /dev/null
+++ b/src/main/java/li/cil/oc/common/tileentity/Hologram.scala
@@ -0,0 +1,93 @@
+package li.cil.oc.common.tileentity
+
+import cpw.mods.fml.relauncher.{Side, SideOnly}
+import li.cil.oc.api.network._
+import li.cil.oc.server.{PacketSender => ServerPacketSender}
+import li.cil.oc.{Settings, api}
+import net.minecraft.nbt.NBTTagCompound
+import net.minecraft.util.AxisAlignedBB
+import net.minecraftforge.common.ForgeDirection
+
+class Hologram extends Environment with SidedEnvironment {
+  val node = api.Network.newNode(this, Visibility.Network).
+    withComponent("hologram").
+    withConnector().
+    create()
+
+  val width = 3 * 16
+
+  val height = 2 * 16 // 32 bit in an int
+
+  val volume = new Array[Int](width * width)
+
+  // Whether we need to send an update packet/recompile our display list.
+  var dirty = false
+
+  // Time to wait before sending another update packet.
+  var cooldown = 0
+
+  // ----------------------------------------------------------------------- //
+
+  override def canConnect(side: ForgeDirection) = side != ForgeDirection.UP
+
+  override def sidedNode(side: ForgeDirection) = node
+
+  // ----------------------------------------------------------------------- //
+
+  @Callback(direct = true, doc = """function(x:number, z:number):number -- Returns the bit mask representing the specified column.""")
+  def get(computer: Context, args: Arguments): Array[AnyRef] = {
+    val x = args.checkInteger(0) - 1
+    val z = args.checkInteger(1) - 1
+    result(volume(x + z * width))
+  }
+
+  @Callback(direct = true, limit = 256, doc = """function(x:number, z:number, value:number) -- Set the bit mask for the specified column.""")
+  def set(computer: Context, args: Arguments): Array[AnyRef] = {
+    val x = args.checkInteger(0) - 1
+    val z = args.checkInteger(1) - 1
+    val value = args.checkInteger(2)
+    volume(x + z * width) = value
+    dirty = true
+    null
+  }
+
+  // ----------------------------------------------------------------------- //
+
+  override def updateEntity() {
+    super.updateEntity()
+    if (isServer && dirty) {
+      cooldown -= 1
+      if (cooldown <= 0) {
+        dirty = false
+        cooldown = 10
+        ServerPacketSender.sendHologramSet(this)
+      }
+    }
+  }
+
+  // ----------------------------------------------------------------------- //
+
+  override def getRenderBoundingBox = AxisAlignedBB.getAABBPool.getAABB(xCoord - 1, yCoord, zCoord - 1, xCoord + 2, yCoord + 3, zCoord + 2)
+
+  override def readFromNBT(nbt: NBTTagCompound) {
+    super.readFromNBT(nbt)
+    nbt.getIntArray(Settings.namespace + "volume").copyToArray(volume)
+  }
+
+  override def writeToNBT(nbt: NBTTagCompound) {
+    super.writeToNBT(nbt)
+    nbt.setIntArray(Settings.namespace + "volume", volume)
+  }
+
+  @SideOnly(Side.CLIENT)
+  override def readFromNBTForClient(nbt: NBTTagCompound) {
+    super.readFromNBTForClient(nbt)
+    nbt.getIntArray("volume").copyToArray(volume)
+    dirty = true
+  }
+
+  override def writeToNBTForClient(nbt: NBTTagCompound) {
+    super.writeToNBTForClient(nbt)
+    nbt.setIntArray("volume", volume)
+  }
+}
diff --git a/src/main/java/li/cil/oc/server/PacketSender.scala b/src/main/java/li/cil/oc/server/PacketSender.scala
index 2e4ee1aaa..2290137f8 100644
--- a/src/main/java/li/cil/oc/server/PacketSender.scala
+++ b/src/main/java/li/cil/oc/server/PacketSender.scala
@@ -55,6 +55,16 @@ object PacketSender {
     pb.sendToNearbyPlayers(t)
   }
 
+  def sendHologramSet(t: Hologram) {
+    val pb = new PacketBuilder(PacketType.HologramSet)
+
+    pb.writeTileEntity(t)
+    pb.writeInt(t.volume.length)
+    t.volume.foreach(pb.writeInt)
+
+    pb.sendToNearbyPlayers(t)
+  }
+
   def sendPowerState(t: PowerInformation) {
     val pb = new PacketBuilder(PacketType.PowerState)
 
diff --git a/src/main/resources/assets/opencomputers/recipes/default.recipes b/src/main/resources/assets/opencomputers/recipes/default.recipes
index e901711bb..8534bb21f 100644
--- a/src/main/resources/assets/opencomputers/recipes/default.recipes
+++ b/src/main/resources/assets/opencomputers/recipes/default.recipes
@@ -271,7 +271,7 @@ powerDistributor {
 rack {
   input: [["oc:circuitTier2", "oc:componentCardWLan", "oc:circuitTier2"]
           [fenceIron, chest, fenceIron]
-          ["oc:craftingRouter", "oc:craftingCircuitBoardPrinted","oc:craftingPowerDistributor"]]
+          ["oc:craftingRouter", "oc:craftingCircuitBoardPrinted", "oc:craftingPowerDistributor"]]
 }
 redstone {
   input: [[ingotIron, blockRedstone, ingotIron]
@@ -302,4 +302,9 @@ screen3 {
   input: [[obsidian, yellowDust, obsidian]
           [yellowDust, "oc:circuitTier3", glass]
           [obsidian, yellowDust, obsidian]]
+}
+hologram {
+  input: [[obsidian, glass, obsidian]
+          ["oc:craftingCircuitBoardPrinted", diamond, "oc:craftingCircuitBoardPrinted"]
+          ["oc:circuitTier3", blazeRod, "oc:circuitTier3"]]
 }
\ No newline at end of file
diff --git a/src/main/resources/assets/opencomputers/textures/blocks/hologram_effect.png b/src/main/resources/assets/opencomputers/textures/blocks/hologram_effect.png
new file mode 100644
index 0000000000000000000000000000000000000000..e994756a32b1220e09edb6f9a50463c1de1bade0
GIT binary patch
literal 157
zcmeAS@N?(olHy`uVBq!ia0vp^EFjFm1|(O0oL2{=BuiW)N`mv#O3D+9QW+dm@{>{(
zJaZG%Q-e|yQz{EjrrH1%*?YP;hE&{A>DnpCpvc2K{kSH}m-~XD7g~H9-rFp2*t|G2
z$<Wf_>9R)`*><M7sI<M0G*7?Hr*px5e|hLr@dSq5!F=bwb?mzYG>XB~)z4*}Q$iB}
D{-`x}

literal 0
HcmV?d00001


From 794590399d5e67466e65d628844fb687d97809b3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Wed, 26 Feb 2014 17:03:29 +0100
Subject: [PATCH 08/12] fixed stupid stupid bug that made term.write fail
 horribly when writing multiline strings in non-wrapping mode

---
 src/main/resources/assets/opencomputers/lua/rom/lib/term.lua | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/main/resources/assets/opencomputers/lua/rom/lib/term.lua b/src/main/resources/assets/opencomputers/lua/rom/lib/term.lua
index 111097326..67a5f98d8 100644
--- a/src/main/resources/assets/opencomputers/lua/rom/lib/term.lua
+++ b/src/main/resources/assets/opencomputers/lua/rom/lib/term.lua
@@ -338,7 +338,7 @@ function term.write(value, wrap)
   end
   local blink = term.getCursorBlink()
   term.setCursorBlink(false)
-  local line, nl = value
+  local line, nl
   repeat
     local wrapAfter, margin = math.huge, math.huge
     if wrap then
@@ -356,7 +356,7 @@ function term.write(value, wrap)
       component.gpu.fill(1, h, w, 1, " ")
       cursorY = h
     end
-  until not wrap or not value
+  until not value
   term.setCursorBlink(blink)
 end
 

From e04a8767d641a83ab526fdea46db5a39d05fc527 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Wed, 26 Feb 2014 20:57:36 +0100
Subject: [PATCH 09/12] textures for hologram projector block; caching display
 list for hologram; fixed item bounds; added localization; added clear and
 fill callbacks; fixed pcall and xpcall being exploitable to avoid timeout
 enforcement

---
 src/main/java/li/cil/oc/client/Proxy.scala    |   1 +
 .../tileentity/HologramRenderer.scala         | 147 +++++++++++++-----
 .../renderer/tileentity/ScreenRenderer.scala  |   3 +-
 .../li/cil/oc/common/block/Hologram.scala     |  24 ++-
 .../cil/oc/common/tileentity/Hologram.scala   |  31 +++-
 .../assets/opencomputers/lang/de_DE.lang      |   2 +
 .../assets/opencomputers/lang/en_US.lang      |   2 +
 .../assets/opencomputers/lua/kernel.lua       |  14 +-
 .../textures/blocks/hologram_effect.png       | Bin 157 -> 149 bytes
 .../textures/blocks/hologram_side.png         | Bin 0 -> 185 bytes
 .../textures/blocks/hologram_top.png          | Bin 0 -> 421 bytes
 11 files changed, 172 insertions(+), 52 deletions(-)
 create mode 100644 src/main/resources/assets/opencomputers/textures/blocks/hologram_side.png
 create mode 100644 src/main/resources/assets/opencomputers/textures/blocks/hologram_top.png

diff --git a/src/main/java/li/cil/oc/client/Proxy.scala b/src/main/java/li/cil/oc/client/Proxy.scala
index c72df6230..ee5266fa5 100644
--- a/src/main/java/li/cil/oc/client/Proxy.scala
+++ b/src/main/java/li/cil/oc/client/Proxy.scala
@@ -48,6 +48,7 @@ private[oc] class Proxy extends CommonProxy {
   override def postInit(e: FMLPostInitializationEvent) {
     super.postInit(e)
 
+    TickRegistry.registerTickHandler(HologramRenderer, Side.CLIENT)
     TickRegistry.registerTickHandler(ScreenRenderer, Side.CLIENT)
     if (Settings.get.rTreeDebugRenderer) {
       MinecraftForge.EVENT_BUS.register(WirelessNetworkDebugRenderer)
diff --git a/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala b/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
index c6a8ff2be..991d4a34b 100644
--- a/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
+++ b/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
@@ -1,29 +1,65 @@
 package li.cil.oc.client.renderer.tileentity
 
-import net.minecraft.client.renderer.tileentity.TileEntitySpecialRenderer
-import net.minecraft.tileentity.TileEntity
-import li.cil.oc.common.tileentity.Hologram
-import net.minecraft.client.renderer.Tessellator
-import org.lwjgl.opengl.GL11
-import li.cil.oc.util.RenderState
+import com.google.common.cache.{RemovalNotification, RemovalListener, CacheBuilder}
+import cpw.mods.fml.common.{TickType, ITickHandler}
+import java.util
+import java.util.concurrent.{Callable, TimeUnit}
 import li.cil.oc.client.TexturePreloader
-import net.minecraftforge.client.MinecraftForgeClient
+import li.cil.oc.common.tileentity.Hologram
+import li.cil.oc.util.RenderState
+import net.minecraft.client.renderer.tileentity.TileEntitySpecialRenderer
+import net.minecraft.client.renderer.{GLAllocation, Tessellator}
+import net.minecraft.tileentity.TileEntity
+import org.lwjgl.opengl.GL11
+import scala.util.Random
+
+object HologramRenderer extends TileEntitySpecialRenderer with Callable[Int] with RemovalListener[TileEntity, Int] with ITickHandler {
+  val random = new Random()
+
+  /** We cache the display lists for the projectors we render for performance. */
+  val cache = com.google.common.cache.CacheBuilder.newBuilder().
+    expireAfterAccess(2, TimeUnit.SECONDS).
+    removalListener(this).
+    asInstanceOf[CacheBuilder[Hologram, Int]].
+    build[Hologram, Int]()
+
+  /** Used to pass the current screen along to call(). */
+  private var hologram: Hologram = null
 
-object HologramRenderer extends TileEntitySpecialRenderer {
   override def renderTileEntityAt(te: TileEntity, x: Double, y: Double, z: Double, f: Float) {
-    if (MinecraftForgeClient.getRenderPass != 0) return
-
-    val hologram = te.asInstanceOf[Hologram]
+    hologram = te.asInstanceOf[Hologram]
 
     GL11.glPushAttrib(0xFFFFFFFF)
-    GL11.glDisable(GL11.GL_CULL_FACE)
-
-//    RenderState.disableLighting()
     RenderState.makeItBlend()
 
     GL11.glPushMatrix()
+
+    GL11.glScaled(1.01, 1.01, 1.01) // Avoid z-fighting with other blocks.
     GL11.glTranslated(x - 1, y + 0.5, z - 1)
 
+    if (random.nextDouble() < 0.025) {
+      GL11.glScaled(1 + random.nextGaussian() * 0.01, 1 + random.nextGaussian() * 0.001, 1 + random.nextGaussian() * 0.01)
+      GL11.glTranslated(random.nextGaussian() * 0.01, random.nextGaussian() * 0.01, random.nextGaussian() * 0.01)
+    }
+
+    GL11.glColorMask(false, false, false, false)
+    val list = cache.get(hologram, this)
+    compileOrDraw(list)
+    GL11.glColorMask(true, true, true, true)
+    GL11.glDepthFunc(GL11.GL_EQUAL)
+    compileOrDraw(list)
+
+    GL11.glPopMatrix()
+    GL11.glPopAttrib()
+  }
+
+  def compileOrDraw(list: Int) = if (hologram.dirty) {
+    val doCompile = !RenderState.compilingDisplayList
+    if (doCompile) {
+      hologram.dirty = false
+      GL11.glNewList(list, GL11.GL_COMPILE_AND_EXECUTE)
+    }
+
     def isSolid(hx: Int, hy: Int, hz: Int) = {
       hx >= 0 && hy >= 0 && hz >= 0 && hx < hologram.width && hy < hologram.height && hz < hologram.width &&
         (hologram.volume(hx + hz * hologram.width) & (1 << hy)) != 0
@@ -56,54 +92,53 @@ object HologramRenderer extends TileEntitySpecialRenderer {
             // South
             if (!isSolid(hx, hy, hz + 1)) {
               t.setNormal(0, 0, 1)
-              t.addVertex(wx + s, wy + s, wz + s) // 5
-              t.addVertex(wx + 0, wy + s, wz + s) // 4
-              t.addVertex(wx + 0, wy + 0, wz + s) // 7
-              t.addVertex(wx + s, wy + 0, wz + s) // 6
+              t.addVertexWithUV(wx + s, wy + s, wz + s, 0, 0) // 5
+              t.addVertexWithUV(wx + 0, wy + s, wz + s, 1, 0) // 4
+              t.addVertexWithUV(wx + 0, wy + 0, wz + s, 1, 1) // 7
+              t.addVertexWithUV(wx + s, wy + 0, wz + s, 0, 1) // 6
             }
             // North
             if (!isSolid(hx, hy, hz - 1)) {
               t.setNormal(0, 0, -1)
-              t.addVertex(wx + s, wy + 0, wz + 0) // 3
-              t.addVertex(wx + 0, wy + 0, wz + 0) // 2
-              t.addVertex(wx + 0, wy + s, wz + 0) // 1
-              t.addVertex(wx + s, wy + s, wz + 0) // 0
+              t.addVertexWithUV(wx + s, wy + 0, wz + 0, 0, 0) // 3
+              t.addVertexWithUV(wx + 0, wy + 0, wz + 0, 1, 0) // 2
+              t.addVertexWithUV(wx + 0, wy + s, wz + 0, 1, 1) // 1
+              t.addVertexWithUV(wx + s, wy + s, wz + 0, 0, 1) // 0
             }
 
             // East
             if (!isSolid(hx + 1, hy, hz)) {
               t.setNormal(1, 0, 0)
-              t.addVertex(wx + s, wy + s, wz + s) // 5
-              t.addVertex(wx + s, wy + 0, wz + s) // 6
-              t.addVertex(wx + s, wy + 0, wz + 0) // 3
-              t.addVertex(wx + s, wy + s, wz + 0) // 0
+              t.addVertexWithUV(wx + s, wy + s, wz + s, 1, 0) // 5
+              t.addVertexWithUV(wx + s, wy + 0, wz + s, 1, 1) // 6
+              t.addVertexWithUV(wx + s, wy + 0, wz + 0, 0, 1) // 3
+              t.addVertexWithUV(wx + s, wy + s, wz + 0, 0, 0) // 0
             }
             // West
             if (!isSolid(hx - 1, hy, hz)) {
               t.setNormal(-1, 0, 0)
-              t.addVertex(wx + 0, wy + 0, wz + s) // 7
-              t.addVertex(wx + 0, wy + s, wz + s) // 4
-              t.addVertex(wx + 0, wy + s, wz + 0) // 1
-              t.addVertex(wx + 0, wy + 0, wz + 0) // 2
+              t.addVertexWithUV(wx + 0, wy + 0, wz + s, 1, 0) // 7
+              t.addVertexWithUV(wx + 0, wy + s, wz + s, 1, 1) // 4
+              t.addVertexWithUV(wx + 0, wy + s, wz + 0, 0, 1) // 1
+              t.addVertexWithUV(wx + 0, wy + 0, wz + 0, 0, 0) // 2
             }
 
             // Up
             if (!isSolid(hx, hy + 1, hz)) {
               t.setNormal(0, 1, 0)
-              t.addVertex(wx + s, wy + s, wz + 0) // 0
-              t.addVertex(wx + 0, wy + s, wz + 0) // 1
-              t.addVertex(wx + 0, wy + s, wz + s) // 4
-              t.addVertex(wx + s, wy + s, wz + s) // 5
+              t.addVertexWithUV(wx + s, wy + s, wz + 0, 0, 0) // 0
+              t.addVertexWithUV(wx + 0, wy + s, wz + 0, 1, 0) // 1
+              t.addVertexWithUV(wx + 0, wy + s, wz + s, 1, 1) // 4
+              t.addVertexWithUV(wx + s, wy + s, wz + s, 0, 1) // 5
             }
             // Down
             if (!isSolid(hx, hy - 1, hz)) {
               t.setNormal(0, -1, 0)
-              t.addVertex(wx + s, wy + 0, wz + s) // 6
-              t.addVertex(wx + 0, wy + 0, wz + s) // 7
-              t.addVertex(wx + 0, wy + 0, wz + 0) // 2
-              t.addVertex(wx + s, wy + 0, wz + 0) // 3
+              t.addVertexWithUV(wx + s, wy + 0, wz + s, 0, 0) // 6
+              t.addVertexWithUV(wx + 0, wy + 0, wz + s, 1, 0) // 7
+              t.addVertexWithUV(wx + 0, wy + 0, wz + 0, 1, 1) // 2
+              t.addVertexWithUV(wx + s, wy + 0, wz + 0, 0, 1) // 3
             }
-
           }
         }
       }
@@ -111,7 +146,37 @@ object HologramRenderer extends TileEntitySpecialRenderer {
 
     t.draw()
 
-    GL11.glPopMatrix()
-    GL11.glPopAttrib()
+    if (doCompile) {
+      GL11.glEndList()
+    }
+
+    true
   }
+  else GL11.glCallList(list)
+
+  // ----------------------------------------------------------------------- //
+  // Cache
+  // ----------------------------------------------------------------------- //
+
+  def call = {
+    val list = GLAllocation.generateDisplayLists(1)
+    hologram.dirty = true // Force compilation.
+    list
+  }
+
+  def onRemoval(e: RemovalNotification[TileEntity, Int]) {
+    GLAllocation.deleteDisplayLists(e.getValue)
+  }
+
+  // ----------------------------------------------------------------------- //
+  // ITickHandler
+  // ----------------------------------------------------------------------- //
+
+  def getLabel = "OpenComputers.Hologram"
+
+  def ticks() = util.EnumSet.of(TickType.CLIENT)
+
+  def tickStart(tickType: util.EnumSet[TickType], tickData: AnyRef*) = cache.cleanUp()
+
+  def tickEnd(tickType: util.EnumSet[TickType], tickData: AnyRef*) {}
 }
diff --git a/src/main/java/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala b/src/main/java/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala
index 53da985c4..06c847d23 100644
--- a/src/main/java/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala
+++ b/src/main/java/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala
@@ -74,8 +74,7 @@ object ScreenRenderer extends TileEntitySpecialRenderer with Callable[Int] with
 
     if (screen.hasPower) {
       MonospaceFontRenderer.init(tileEntityRenderer.renderEngine)
-      val list = cache.get(screen, this)
-      compileOrDraw(list)
+      compileOrDraw(cache.get(screen, this))
     }
 
     GL11.glPopMatrix()
diff --git a/src/main/java/li/cil/oc/common/block/Hologram.scala b/src/main/java/li/cil/oc/common/block/Hologram.scala
index 9b926bb38..993f325ec 100644
--- a/src/main/java/li/cil/oc/common/block/Hologram.scala
+++ b/src/main/java/li/cil/oc/common/block/Hologram.scala
@@ -7,23 +7,43 @@ import net.minecraft.entity.player.EntityPlayer
 import net.minecraft.item.{ItemStack, EnumRarity}
 import net.minecraft.world.{World, IBlockAccess}
 import net.minecraftforge.common.ForgeDirection
-import net.minecraft.util.AxisAlignedBB
+import net.minecraft.util.{Icon, AxisAlignedBB}
+import net.minecraft.client.renderer.texture.IconRegister
+import li.cil.oc.Settings
 
 class Hologram(val parent: SpecialDelegator) extends SpecialDelegate {
   val unlocalizedName = "Hologram"
 
+  private val icons = Array.fill[Icon](6)(null)
+
   override def rarity = EnumRarity.rare
 
   override def tooltipLines(stack: ItemStack, player: EntityPlayer, tooltip: util.List[String], advanced: Boolean) {
     tooltip.addAll(Tooltip.get(unlocalizedName))
   }
 
+  override def icon(side: ForgeDirection) = Some(icons(side.ordinal()))
+
   override def luminance(world: IBlockAccess, x: Int, y: Int, z: Int) = 15
 
   override def isSolid(world: IBlockAccess, x: Int, y: Int, z: Int, side: ForgeDirection) = side == ForgeDirection.DOWN
 
   override def bounds(world: IBlockAccess, x: Int, y: Int, z: Int) =
-    AxisAlignedBB.getAABBPool.getAABB(0, 0, 0, 1, 0.2f, 1)
+    AxisAlignedBB.getAABBPool.getAABB(0, 0, 0, 1, 3 / 16f, 1)
+
+  override def itemBounds() {
+    parent.setBlockBounds(AxisAlignedBB.getAABBPool.getAABB(0, 0, 0, 1, 3 / 16f, 1))
+  }
+
+  override def registerIcons(iconRegister: IconRegister) = {
+    icons(ForgeDirection.DOWN.ordinal) = iconRegister.registerIcon(Settings.resourceDomain + ":generic_top")
+    icons(ForgeDirection.UP.ordinal) = iconRegister.registerIcon(Settings.resourceDomain + ":hologram_top")
+
+    icons(ForgeDirection.NORTH.ordinal) = iconRegister.registerIcon(Settings.resourceDomain + ":hologram_side")
+    icons(ForgeDirection.SOUTH.ordinal) = icons(ForgeDirection.NORTH.ordinal)
+    icons(ForgeDirection.WEST.ordinal) = icons(ForgeDirection.NORTH.ordinal)
+    icons(ForgeDirection.EAST.ordinal) = icons(ForgeDirection.NORTH.ordinal)
+  }
 
   // ----------------------------------------------------------------------- //
 
diff --git a/src/main/java/li/cil/oc/common/tileentity/Hologram.scala b/src/main/java/li/cil/oc/common/tileentity/Hologram.scala
index 94dba39ce..f0ed42622 100644
--- a/src/main/java/li/cil/oc/common/tileentity/Hologram.scala
+++ b/src/main/java/li/cil/oc/common/tileentity/Hologram.scala
@@ -34,15 +34,22 @@ class Hologram extends Environment with SidedEnvironment {
 
   // ----------------------------------------------------------------------- //
 
+  @Callback(doc = """function() -- Clears the hologram.""")
+  def clear(computer: Context, args: Arguments): Array[AnyRef] = this.synchronized {
+    for (i <- 0 until volume.length) volume(i) = 0
+    dirty = true
+    null
+  }
+
   @Callback(direct = true, doc = """function(x:number, z:number):number -- Returns the bit mask representing the specified column.""")
-  def get(computer: Context, args: Arguments): Array[AnyRef] = {
+  def get(computer: Context, args: Arguments): Array[AnyRef] = this.synchronized {
     val x = args.checkInteger(0) - 1
     val z = args.checkInteger(1) - 1
     result(volume(x + z * width))
   }
 
   @Callback(direct = true, limit = 256, doc = """function(x:number, z:number, value:number) -- Set the bit mask for the specified column.""")
-  def set(computer: Context, args: Arguments): Array[AnyRef] = {
+  def set(computer: Context, args: Arguments): Array[AnyRef] = this.synchronized {
     val x = args.checkInteger(0) - 1
     val z = args.checkInteger(1) - 1
     val value = args.checkInteger(2)
@@ -51,6 +58,18 @@ class Hologram extends Environment with SidedEnvironment {
     null
   }
 
+  @Callback(direct = true, limit = 128, doc = """function(x:number, z:number, height:number) -- Fills a column to the specified height.""")
+  def fill(computer: Context, args: Arguments): Array[AnyRef] = this.synchronized {
+    val x = args.checkInteger(0) - 1
+    val z = args.checkInteger(1) - 1
+    val height = math.min(32, math.max(0, args.checkInteger(2)))
+    // Bit shifts in the JVM only use the lowest five bits... so we have to
+    // manually check the height, to avoid the shift being a no-op.
+    volume(x + z * width) = if (height > 0) 0xFFFFFFFF >>> (32 - height) else 0
+    dirty = true
+    null
+  }
+
   // ----------------------------------------------------------------------- //
 
   override def updateEntity() {
@@ -67,14 +86,18 @@ class Hologram extends Environment with SidedEnvironment {
 
   // ----------------------------------------------------------------------- //
 
-  override def getRenderBoundingBox = AxisAlignedBB.getAABBPool.getAABB(xCoord - 1, yCoord, zCoord - 1, xCoord + 2, yCoord + 3, zCoord + 2)
+  override def shouldRenderInPass(pass: Int) = pass == 1
+
+  override def getRenderBoundingBox = AxisAlignedBB.getAABBPool.getAABB(xCoord - 1, yCoord, zCoord - 1, xCoord + 2, yCoord + 2.25, zCoord + 2)
+
+  // ----------------------------------------------------------------------- //
 
   override def readFromNBT(nbt: NBTTagCompound) {
     super.readFromNBT(nbt)
     nbt.getIntArray(Settings.namespace + "volume").copyToArray(volume)
   }
 
-  override def writeToNBT(nbt: NBTTagCompound) {
+  override def writeToNBT(nbt: NBTTagCompound) = this.synchronized {
     super.writeToNBT(nbt)
     nbt.setIntArray(Settings.namespace + "volume", volume)
   }
diff --git a/src/main/resources/assets/opencomputers/lang/de_DE.lang b/src/main/resources/assets/opencomputers/lang/de_DE.lang
index c9f1bc053..2b7bc3535 100644
--- a/src/main/resources/assets/opencomputers/lang/de_DE.lang
+++ b/src/main/resources/assets/opencomputers/lang/de_DE.lang
@@ -12,6 +12,7 @@ oc:tile.Case2.name=Computergehäuse (Stufe 3)
 oc:tile.Charger.name=Ladestation
 oc:tile.DiskDrive.name=Diskettenlaufwerk
 oc:tile.Keyboard.name=Tastatur
+oc:tile.Hologram.name=Hologrammprojektor
 oc:tile.PowerConverter.name=Leistungswandler
 oc:tile.PowerDistributor.name=Stromverteiler
 oc:tile.Redstone.name=Redstone-I/O
@@ -136,6 +137,7 @@ oc:tooltip.GraphicsCard=Erlaubt es, den angezeigten Inhalt von Bildschirmen zu 
 oc:tooltip.InternetCard=Diese Karte erlaubt es, HTTP-Anfragen zu senden und echte TCP Sockets zu verwenden.
 oc:tooltip.IronNugget=Ein Nugget, das aus Eisen besteht, darum wird es ja auch Eisennugget genannt, duh...
 oc:tooltip.Keyboard=Kann an Bildschirmen befestigt werden, um auf ihnen zu tippen.
+oc:tooltip.Hologram=Ein Volumendisplay das beliebige, von Computern festgelegte Voxelstrukturen anzeigt.[nl] Auflösung: §f48x32x48§7. [nl] Farbtiefe: §fMonochrom§7.
 oc:tooltip.Memory=Braucht ein jeder Computer, um zu starten. Je mehr vorhanden, desto komplexere Programme können ausgeführt werden.
 oc:tooltip.Microchip=Tritt auch unter dem Alias Integrierter Schaltkreis auf. Keine Ahnung, warum das auch mit Redstone klappt, aber es funktioniert.
 oc:tooltip.NetworkCard=Erlaubt es Computern, die über mehrere Blöcke miteinander verbunden sind (z.B. Kabel), mittels Netzwerknachrichten zu kommunizieren.
diff --git a/src/main/resources/assets/opencomputers/lang/en_US.lang b/src/main/resources/assets/opencomputers/lang/en_US.lang
index b5f8195d6..a1d56e273 100644
--- a/src/main/resources/assets/opencomputers/lang/en_US.lang
+++ b/src/main/resources/assets/opencomputers/lang/en_US.lang
@@ -12,6 +12,7 @@ oc:tile.Case2.name=Computer Case (Tier 3)
 oc:tile.Charger.name=Charger
 oc:tile.DiskDrive.name=Disk Drive
 oc:tile.Keyboard.name=Keyboard
+oc:tile.Hologram.name=Hologram Projector
 oc:tile.PowerConverter.name=Power Converter
 oc:tile.PowerDistributor.name=Power Distributor
 oc:tile.Redstone.name=Redstone I/O
@@ -136,6 +137,7 @@ oc:tooltip.GraphicsCard=Used to change what's displayed on screens.[nl] Maximum
 oc:tooltip.InternetCard=This card allows making HTTP requests and using real TCP sockets.
 oc:tooltip.IronNugget=A nugget made of iron, that's why it's called an Iron Nugget, duh...
 oc:tooltip.Keyboard=Can be attached to screens to allow typing on them.
+oc:tooltip.Hologram=A volumetric display that can be controlled by computers to display arbitrary voxel structures.[nl] Resolution: §f48x32x48§7. [nl] Color depth: §fMonochrome§7.
 oc:tooltip.Memory=Required to get computers to run. The more you have, the more complex the programs you can run.
 oc:tooltip.Microchip=The chip formerly known as Integrated Circuit. I have no idea why this works with redstone, but it does.
 oc:tooltip.NetworkCard=Allows distant computers connected by other blocks (such as cable) to communicate by sending messages to each other.
diff --git a/src/main/resources/assets/opencomputers/lua/kernel.lua b/src/main/resources/assets/opencomputers/lua/kernel.lua
index baec22ae5..cc9946c26 100644
--- a/src/main/resources/assets/opencomputers/lua/kernel.lua
+++ b/src/main/resources/assets/opencomputers/lua/kernel.lua
@@ -1,5 +1,5 @@
 local hookInterval = 100
-local deadline = 0
+local deadline = math.huge
 local function checkDeadline()
   if computer.realTime() > deadline then
     debug.sethook(coroutine.running(), checkDeadline, "", 1)
@@ -91,7 +91,11 @@ sandbox = {
   loadfile = nil, -- in boot/*_base.lua
   next = next,
   pairs = pairs,
-  pcall = pcall,
+  pcall = function(...)
+    local result = table.pack(pcall(...))
+    checkDeadline()
+    return table.unpack(result, 1, result.n)
+  end,
   print = nil, -- in boot/*_base.lua
   rawequal = rawequal,
   rawget = rawget,
@@ -103,7 +107,11 @@ sandbox = {
   tostring = tostring,
   type = type,
   _VERSION = "Lua 5.2",
-  xpcall = xpcall,
+  xpcall = function(...)
+    local result = table.pack(xpcall(...))
+    checkDeadline()
+    return table.unpack(result, 1, result.n)
+  end,
 
   coroutine = {
     create = function(f)
diff --git a/src/main/resources/assets/opencomputers/textures/blocks/hologram_effect.png b/src/main/resources/assets/opencomputers/textures/blocks/hologram_effect.png
index e994756a32b1220e09edb6f9a50463c1de1bade0..5be656cec646fc72f7f889645587f7160bb94b0c 100644
GIT binary patch
delta 83
zcmV-Z0IdI=0hIxeNlZ6ML_t(|+9Zj&4ZtuE!$`!n;r(YynMpE$<>v&jASE9!frF1U
p`W7q1?C?`d9nB$`xuUWJ7yz;;3&QpK@*4mE002ovPDHLkV1mx2BGdo?

delta 91
zcmV-h0Hptw0i6MmNmM^cL_t(|+9Zm(5da|!1DD4s1oYn#RnUY@fbTq@K(nJ&Vlg>D
x<)-4%2DxQKB!=%<H)q=pEYL^4cU9#VU;w*Q4$k(7zR~~y002ovPDHLkV1lGMC6@pI

diff --git a/src/main/resources/assets/opencomputers/textures/blocks/hologram_side.png b/src/main/resources/assets/opencomputers/textures/blocks/hologram_side.png
new file mode 100644
index 0000000000000000000000000000000000000000..99746701ca356674699af832b171d2fa6069b655
GIT binary patch
literal 185
zcmeAS@N?(olHy`uVBq!ia0vp^0wB!63?wyl`GbL!WQl7;NpOBzNqJ&XDuZK6ep0G}
zXKrG8YEWuoN@d~6R2!fo#Q>iWS0Jset*xxAtfZvm=H}+&;-aXi=<4dKrKRQM<mBw^
z{DDK_3{a7tr;B4q#jQIn#|0S_1X`}~F8jy*t>$L)0fs+3H{~X`yqWm4;<lgFiq$UH
cRx2N1;QPcd<H1*^P@ql*Pgg&ebxsLQ0ABbvXaE2J

literal 0
HcmV?d00001

diff --git a/src/main/resources/assets/opencomputers/textures/blocks/hologram_top.png b/src/main/resources/assets/opencomputers/textures/blocks/hologram_top.png
new file mode 100644
index 0000000000000000000000000000000000000000..cebbf9d199eb2d4c92de5e343a2c4696ef866852
GIT binary patch
literal 421
zcmV;W0b2fvP)<h;3K|Lk000e1NJLTq000mG000mO0{{R3C@l|D0000PbVXQnQ*UN;
zcVTj606}DLVr3vnZDD6+Qe|Oed2z{QJOBUyfly3TMF0Q*GiEbVQc@`?DJUo?W|?MC
zP*5i)Cs9#RGcz+XGBRYBWHMwj=>O<tmt{{+PiB~AGG#Jm%w|kXJuxvcGi5VQPEIjm
zF=d!#W0YfLm1Ip#K4Oz%F=H`HOFT2mGiAzUFuyP{#4%)+WJ^muCMG6IN;_hdVogm=
zOG`^L%romUXF&h}0J=#;K~#9!98X7b!$1rJ+jdK`EV(C6Z~uQ_sO1bU7!U=YDiTF?
zgNO<=Fee8m9s>tOOb<E{(cVF?Ng+&weOooNsZtQg4;gR+4#02<(G}|%b16B`sKjo{
zbUhUKmD|u*J!P%P*zK^O?ngKMb&pPDOyq<nvXB0<JYS!ZdyKA_^ODO8jJWrxJ@X5=
zZz+-6WbfzcGTiO55yF2&&6}@{+FS48+m0Og=mW#nRQr0LE>T6}zW@UONl^$t>C(mU
P00000NkvXXu0mjfdWoJX

literal 0
HcmV?d00001


From c3e9ed1e97ccf12581dab102f9d65f00665e2ecc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Thu, 27 Feb 2014 03:25:27 +0100
Subject: [PATCH 10/12] added power consumption for hologram projector; added
 scale setting, so hologram can be from 1x1x1 up to 9x6x9, higher scale
 consumes more energy

---
 src/main/java/li/cil/oc/Settings.scala        |   1 +
 .../java/li/cil/oc/client/PacketHandler.scala |   9 +++
 .../renderer/tileentity/CableRenderer.scala   |  12 +---
 .../tileentity/HologramRenderer.scala         |  13 +++--
 .../java/li/cil/oc/common/PacketType.scala    |   1 +
 .../cil/oc/common/tileentity/Hologram.scala   |  52 +++++++++++++++---
 .../java/li/cil/oc/server/PacketSender.scala  |   9 +++
 .../textures/blocks/hologram_effect.png       | Bin 149 -> 157 bytes
 src/main/resources/reference.conf             |   5 ++
 9 files changed, 79 insertions(+), 23 deletions(-)

diff --git a/src/main/java/li/cil/oc/Settings.scala b/src/main/java/li/cil/oc/Settings.scala
index 6bd97680a..566d9d485 100644
--- a/src/main/java/li/cil/oc/Settings.scala
+++ b/src/main/java/li/cil/oc/Settings.scala
@@ -120,6 +120,7 @@ class Settings(config: Config) {
   val robotCost = config.getDouble("power.cost.robot") max 0
   val sleepCostFactor = config.getDouble("power.cost.sleepFactor") max 0
   val screenCost = config.getDouble("power.cost.screen") max 0
+  val hologramCost = config.getDouble("power.cost.hologram") max 0
   val hddReadCost = (config.getDouble("power.cost.hddRead") max 0) / 1024
   val hddWriteCost = (config.getDouble("power.cost.hddWrite") max 0) / 1024
   val gpuSetCost = (config.getDouble("power.cost.gpuSet") max 0) / Settings.basicScreenPixels
diff --git a/src/main/java/li/cil/oc/client/PacketHandler.scala b/src/main/java/li/cil/oc/client/PacketHandler.scala
index 47a7c593a..28b8a04a6 100644
--- a/src/main/java/li/cil/oc/client/PacketHandler.scala
+++ b/src/main/java/li/cil/oc/client/PacketHandler.scala
@@ -26,6 +26,7 @@ class PacketHandler extends CommonPacketHandler {
       case PacketType.ChargerState => onChargerState(p)
       case PacketType.ComputerState => onComputerState(p)
       case PacketType.ComputerUserList => onComputerUserList(p)
+      case PacketType.HologramScale => onHologramScale(p)
       case PacketType.HologramSet => onHologramSet(p)
       case PacketType.PowerState => onPowerState(p)
       case PacketType.RedstoneState => onRedstoneState(p)
@@ -101,6 +102,14 @@ class PacketHandler extends CommonPacketHandler {
       case _ => // Invalid packet.
     }
 
+  def onHologramScale(p: PacketParser) =
+    p.readTileEntity[Hologram]() match {
+      case Some(t) =>
+        t.scale = p.readDouble()
+        t.dirty = true
+      case _ => // Invalid packet.
+    }
+
   def onHologramSet(p: PacketParser) =
     p.readTileEntity[Hologram]() match {
       case Some(t) =>
diff --git a/src/main/java/li/cil/oc/client/renderer/tileentity/CableRenderer.scala b/src/main/java/li/cil/oc/client/renderer/tileentity/CableRenderer.scala
index 35bde5a61..b485b0892 100644
--- a/src/main/java/li/cil/oc/client/renderer/tileentity/CableRenderer.scala
+++ b/src/main/java/li/cil/oc/client/renderer/tileentity/CableRenderer.scala
@@ -40,6 +40,7 @@ object CableRenderer extends TileEntitySpecialRenderer {
 
     for (mask <- 0 to 0xFF >> 2) {
       GL11.glNewList(displayLists + mask, GL11.GL_COMPILE)
+      t.startDrawingQuads()
       for (side <- ForgeDirection.VALID_DIRECTIONS) {
         val connects = (side.flag & mask) != 0
         val z = if (connects) 0 else lb
@@ -48,7 +49,6 @@ object CableRenderer extends TileEntitySpecialRenderer {
           exists(s => (s.flag & mask) != 0)) uo
         else 0
 
-        t.startDrawingQuads()
         t.setNormal(side.offsetX, side.offsetY, -side.offsetZ)
         val (tx, ty, tz, u, v) = side match {
           case ForgeDirection.WEST => (Array.fill(4)(z), t2, t1, uv1.reverse, uv2)
@@ -63,7 +63,6 @@ object CableRenderer extends TileEntitySpecialRenderer {
         t.addVertexWithUV(tx(1), ty(1), tz(1), u(1) + uc, v(1))
         t.addVertexWithUV(tx(2), ty(2), tz(2), u(2) + uc, v(2))
         t.addVertexWithUV(tx(3), ty(3), tz(3), u(3) + uc, v(3))
-        t.draw()
 
         if (connects) {
           val (axis, sign, uv1, uv2, uv3, uv4) = side match {
@@ -79,39 +78,32 @@ object CableRenderer extends TileEntitySpecialRenderer {
           val o1 = offsets((axis + sign + 3) % 3)
           val o2 = offsets((axis - sign + 3) % 3)
 
-          t.startDrawingQuads()
           normal(side, 0)
           t.addVertexWithUV(tx(0) - sign * tl(0), ty(0) - sign * tl(1), tz(0) - sign * tl(2), u(uv(0 + uv1)) + uo, v(uv(0 + uv1)) * vs)
           t.addVertexWithUV(tx(1) - sign * tl(0), ty(1) - sign * tl(1), tz(1) - sign * tl(2), u(uv(1 + uv1)) + uo, v(uv(1 + uv1)) * vs)
           t.addVertexWithUV(tx(2) + o1(0), ty(2) + o1(1), tz(2) + o1(2), u(uv(2 + uv1)) + uo, v(uv(2 + uv1)) * vs)
           t.addVertexWithUV(tx(3) + o1(0), ty(3) + o1(1), tz(3) + o1(2), u(uv(3 + uv1)) + uo, v(uv(3 + uv1)) * vs)
-          t.draw()
 
-          t.startDrawingQuads()
           normal(side, 1)
           t.addVertexWithUV(tx(0) - o1(0), ty(0) - o1(1), tz(0) - o1(2), u(uv(0 + uv2)) + uo, v(uv(0 + uv2)) * vs)
           t.addVertexWithUV(tx(1) - o1(0), ty(1) - o1(1), tz(1) - o1(2), u(uv(1 + uv2)) + uo, v(uv(1 + uv2)) * vs)
           t.addVertexWithUV(tx(2) - sign * tl(0), ty(2) - sign * tl(1), tz(2) - sign * tl(2), u(uv(2 + uv2)) + uo, v(uv(2 + uv2)) * vs)
           t.addVertexWithUV(tx(3) - sign * tl(0), ty(3) - sign * tl(1), tz(3) - sign * tl(2), u(uv(3 + uv2)) + uo, v(uv(3 + uv2)) * vs)
-          t.draw()
 
-          t.startDrawingQuads()
           normal(side, 2)
           t.addVertexWithUV(tx(0) - sign * tl(0), ty(0) - sign * tl(1), tz(0) - sign * tl(2), u(uv(0 + uv3)) + uo, v(uv(0 + uv3)) * vs)
           t.addVertexWithUV(tx(1) - o2(0), ty(1) - o2(1), tz(1) - o2(2), u(uv(1 + uv3)) + uo, v(uv(1 + uv3)) * vs)
           t.addVertexWithUV(tx(2) - o2(0), ty(2) - o2(1), tz(2) - o2(2), u(uv(2 + uv3)) + uo, v(uv(2 + uv3)) * vs)
           t.addVertexWithUV(tx(3) - sign * tl(0), ty(3) - sign * tl(1), tz(3) - sign * tl(2), u(uv(3 + uv3)) + uo, v(uv(3 + uv3)) * vs)
-          t.draw()
 
-          t.startDrawingQuads()
           normal(side, 3)
           t.addVertexWithUV(tx(0) + o2(0), ty(0) + o2(1), tz(0) + o2(2), u(uv(0 + uv4)) + uo, v(uv(0 + uv4)) * vs)
           t.addVertexWithUV(tx(1) - sign * tl(0), ty(1) - sign * tl(1), tz(1) - sign * tl(2), u(uv(1 + uv4)) + uo, v(uv(1 + uv4)) * vs)
           t.addVertexWithUV(tx(2) - sign * tl(0), ty(2) - sign * tl(1), tz(2) - sign * tl(2), u(uv(2 + uv4)) + uo, v(uv(2 + uv4)) * vs)
           t.addVertexWithUV(tx(3) + o2(0), ty(3) + o2(1), tz(3) + o2(2), u(uv(3 + uv4)) + uo, v(uv(3 + uv4)) * vs)
-          t.draw()
         }
       }
+      t.draw()
 
       GL11.glEndList()
     }
diff --git a/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala b/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
index 991d4a34b..da5692247 100644
--- a/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
+++ b/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
@@ -28,15 +28,16 @@ object HologramRenderer extends TileEntitySpecialRenderer with Callable[Int] wit
 
   override def renderTileEntityAt(te: TileEntity, x: Double, y: Double, z: Double, f: Float) {
     hologram = te.asInstanceOf[Hologram]
+    if (!hologram.hasPower) return
 
     GL11.glPushAttrib(0xFFFFFFFF)
-    RenderState.makeItBlend()
 
     GL11.glPushMatrix()
+    GL11.glTranslated(x + 0.5, y + 0.5, z + 0.5)
+    GL11.glScaled(1.001, 1.001, 1.001) // Avoid z-fighting with other blocks.
+    GL11.glTranslated(-1.5 * hologram.scale, 0, -1.5 * hologram.scale)
 
-    GL11.glScaled(1.01, 1.01, 1.01) // Avoid z-fighting with other blocks.
-    GL11.glTranslated(x - 1, y + 0.5, z - 1)
-
+    // Do a bit of flickering, because that's what holograms do!
     if (random.nextDouble() < 0.025) {
       GL11.glScaled(1 + random.nextGaussian() * 0.01, 1 + random.nextGaussian() * 0.001, 1 + random.nextGaussian() * 0.01)
       GL11.glTranslated(random.nextGaussian() * 0.01, random.nextGaussian() * 0.01, random.nextGaussian() * 0.01)
@@ -68,9 +69,9 @@ object HologramRenderer extends TileEntitySpecialRenderer with Callable[Int] wit
     bindTexture(TexturePreloader.blockHologram)
     val t = Tessellator.instance
     t.startDrawingQuads()
-    t.setColorRGBA_F(1, 1, 1, 0.7f)
+    t.setColorRGBA_F(1, 1, 1, 0.5f)
 
-    val s = 1f / 16f
+    val s = 1f / 16f * hologram.scale
     for (hx <- 0 until hologram.width) {
       val wx = hx * s
       for (hz <- 0 until hologram.width) {
diff --git a/src/main/java/li/cil/oc/common/PacketType.scala b/src/main/java/li/cil/oc/common/PacketType.scala
index 11013c6c1..059b3d2f1 100644
--- a/src/main/java/li/cil/oc/common/PacketType.scala
+++ b/src/main/java/li/cil/oc/common/PacketType.scala
@@ -8,6 +8,7 @@ object PacketType extends Enumeration {
   ChargerState,
   ComputerState,
   ComputerUserList,
+  HologramScale,
   HologramSet,
   PowerState,
   RedstoneState,
diff --git a/src/main/java/li/cil/oc/common/tileentity/Hologram.scala b/src/main/java/li/cil/oc/common/tileentity/Hologram.scala
index f0ed42622..f5f24e323 100644
--- a/src/main/java/li/cil/oc/common/tileentity/Hologram.scala
+++ b/src/main/java/li/cil/oc/common/tileentity/Hologram.scala
@@ -20,12 +20,20 @@ class Hologram extends Environment with SidedEnvironment {
 
   val volume = new Array[Int](width * width)
 
+  // Render scale.
+  var scale = 1.0
+
+  // Relative number of lit columns (for energy cost).
+  var litRatio = -1.0
+
   // Whether we need to send an update packet/recompile our display list.
   var dirty = false
 
   // Time to wait before sending another update packet.
   var cooldown = 0
 
+  var hasPower = true
+
   // ----------------------------------------------------------------------- //
 
   override def canConnect(side: ForgeDirection) = side != ForgeDirection.UP
@@ -38,6 +46,7 @@ class Hologram extends Environment with SidedEnvironment {
   def clear(computer: Context, args: Arguments): Array[AnyRef] = this.synchronized {
     for (i <- 0 until volume.length) volume(i) = 0
     dirty = true
+    litRatio = 0
     null
   }
 
@@ -55,6 +64,7 @@ class Hologram extends Environment with SidedEnvironment {
     val value = args.checkInteger(2)
     volume(x + z * width) = value
     dirty = true
+    litRatio = -1
     null
   }
 
@@ -67,6 +77,19 @@ class Hologram extends Environment with SidedEnvironment {
     // manually check the height, to avoid the shift being a no-op.
     volume(x + z * width) = if (height > 0) 0xFFFFFFFF >>> (32 - height) else 0
     dirty = true
+    litRatio = -1
+    null
+  }
+
+  @Callback(doc = """function():number -- Returns the render scale of the hologram.""")
+  def getScale(computer: Context, args: Arguments): Array[AnyRef] = {
+    result(scale)
+  }
+
+  @Callback(doc = """function(value:number) -- Set the render scale. A larger scale consumes more energy.""")
+  def setScale(computer: Context, args: Arguments): Array[AnyRef] = {
+    scale = math.max(0.333333, math.min(3, args.checkDouble(0)))
+    ServerPacketSender.sendHologramScale(this)
     null
   }
 
@@ -74,13 +97,24 @@ class Hologram extends Environment with SidedEnvironment {
 
   override def updateEntity() {
     super.updateEntity()
-    if (isServer && dirty) {
-      cooldown -= 1
-      if (cooldown <= 0) {
-        dirty = false
-        cooldown = 10
-        ServerPacketSender.sendHologramSet(this)
+    if (isServer) {
+      if (dirty) {
+        cooldown -= 1
+        if (cooldown <= 0) {
+          dirty = false
+          cooldown = 10
+          ServerPacketSender.sendHologramSet(this)
+        }
       }
+      if (litRatio < 0) {
+        litRatio = 0
+        for (i <- 0 until volume.length) {
+          if (volume(i) != 0) litRatio += 1
+        }
+        litRatio /= volume.length
+      }
+
+      hasPower = node.changeBuffer(-Settings.get.hologramCost * litRatio * scale) == 0
     }
   }
 
@@ -88,29 +122,33 @@ class Hologram extends Environment with SidedEnvironment {
 
   override def shouldRenderInPass(pass: Int) = pass == 1
 
-  override def getRenderBoundingBox = AxisAlignedBB.getAABBPool.getAABB(xCoord - 1, yCoord, zCoord - 1, xCoord + 2, yCoord + 2.25, zCoord + 2)
+  override def getRenderBoundingBox = AxisAlignedBB.getAABBPool.getAABB(xCoord + 0.5 - 1.5 * scale, yCoord, zCoord - scale, xCoord + 0.5 + 1.5 * scale, yCoord + 0.25 + 2 * scale, zCoord + 0.5 + 1.5 * scale)
 
   // ----------------------------------------------------------------------- //
 
   override def readFromNBT(nbt: NBTTagCompound) {
     super.readFromNBT(nbt)
     nbt.getIntArray(Settings.namespace + "volume").copyToArray(volume)
+    scale = nbt.getDouble(Settings.namespace + "scale")
   }
 
   override def writeToNBT(nbt: NBTTagCompound) = this.synchronized {
     super.writeToNBT(nbt)
     nbt.setIntArray(Settings.namespace + "volume", volume)
+    nbt.setDouble(Settings.namespace + "scale", scale)
   }
 
   @SideOnly(Side.CLIENT)
   override def readFromNBTForClient(nbt: NBTTagCompound) {
     super.readFromNBTForClient(nbt)
     nbt.getIntArray("volume").copyToArray(volume)
+    scale = nbt.getDouble("scale")
     dirty = true
   }
 
   override def writeToNBTForClient(nbt: NBTTagCompound) {
     super.writeToNBTForClient(nbt)
     nbt.setIntArray("volume", volume)
+    nbt.setDouble("scale", scale)
   }
 }
diff --git a/src/main/java/li/cil/oc/server/PacketSender.scala b/src/main/java/li/cil/oc/server/PacketSender.scala
index 2290137f8..55dc419b3 100644
--- a/src/main/java/li/cil/oc/server/PacketSender.scala
+++ b/src/main/java/li/cil/oc/server/PacketSender.scala
@@ -55,6 +55,15 @@ object PacketSender {
     pb.sendToNearbyPlayers(t)
   }
 
+  def sendHologramScale(t: Hologram) {
+    val pb = new PacketBuilder(PacketType.HologramScale)
+
+    pb.writeTileEntity(t)
+    pb.writeDouble(t.scale)
+
+    pb.sendToNearbyPlayers(t)
+  }
+
   def sendHologramSet(t: Hologram) {
     val pb = new PacketBuilder(PacketType.HologramSet)
 
diff --git a/src/main/resources/assets/opencomputers/textures/blocks/hologram_effect.png b/src/main/resources/assets/opencomputers/textures/blocks/hologram_effect.png
index 5be656cec646fc72f7f889645587f7160bb94b0c..154039406c1e4562c5c11f4c691b26801287cc1d 100644
GIT binary patch
delta 103
zcmbQrIG1sPBnLAC1H(N1JfDe*8X=+qJ|V6QR~Q%`F)%!4V7Sb{_=J(+5(DE^#;dv_
z$AJpvJY5_^DsCkuB&4M#C!{2$09grX2?>cQNsJr@42+cw%6HrMhyYbGc)I$ztaD0e
F0s!CT9rpkL

delta 95
zcmV-l0HFV!0hIxe83+ad0061+o_>)bC`>m=L_t(|+9Zj&4ZtuE!$`!n;r(YynMpE$
z<>v&jASE9!frF1U`W7q1?C?`d9nB$`xuUWJ7yz;;3&QpK@*4mE002ovPDHLkV1oY?
BCPDxJ

diff --git a/src/main/resources/reference.conf b/src/main/resources/reference.conf
index cb2bf7eff..e56652212 100644
--- a/src/main/resources/reference.conf
+++ b/src/main/resources/reference.conf
@@ -471,6 +471,11 @@ opencomputers {
           # tick.
           screen: 0.05
 
+          # The amount of energy a hologram projetor consumes per tick. This
+          # is the cost if every column is lit. If not a single voxel is
+          # displayed the hologram projector will not drain energy.
+          hologram: 0.2
+
           # Energy it takes read one kilobyte from a file system. Note that non
           # I/O operations on file systems such as `list` or `getFreeSpace` do
           # *not* consume power. Note that this very much determines how much

From 9dbe22562331cbbe564dfc51d66e1490c3fb769c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Thu, 27 Feb 2014 04:21:21 +0100
Subject: [PATCH 11/12] fixed possibility of math.random pushing a LuaError
 (userdata); fixed shell immediately restarting after errors if there were
 pending signals

---
 src/main/java/li/cil/oc/util/LuaStateFactory.scala         | 6 +++---
 src/main/resources/assets/opencomputers/lua/rom/bin/sh.lua | 2 +-
 src/main/resources/assets/opencomputers/lua/rom/init.lua   | 3 ++-
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/src/main/java/li/cil/oc/util/LuaStateFactory.scala b/src/main/java/li/cil/oc/util/LuaStateFactory.scala
index 9f7179d76..19722d9cf 100644
--- a/src/main/java/li/cil/oc/util/LuaStateFactory.scala
+++ b/src/main/java/li/cil/oc/util/LuaStateFactory.scala
@@ -217,12 +217,12 @@ object LuaStateFactory {
           lua.getTop match {
             case 0 => lua.pushNumber(random.nextDouble())
             case 1 =>
-              val u = lua.checkInteger(1)
+              val u = lua.checkNumber(1).toInt
               lua.checkArg(1, 1 < u, "interval is empty")
               lua.pushInteger(1 + random.nextInt(u))
             case 2 =>
-              val l = lua.checkInteger(1)
-              val u = lua.checkInteger(2)
+              val l = lua.checkNumber(1).toInt
+              val u = lua.checkNumber(2).toInt
               lua.checkArg(1, l < u, "interval is empty")
               lua.pushInteger(l + random.nextInt(u - (l - 1)))
             case _ => throw new IllegalArgumentException("wrong number of arguments")
diff --git a/src/main/resources/assets/opencomputers/lua/rom/bin/sh.lua b/src/main/resources/assets/opencomputers/lua/rom/bin/sh.lua
index 2ec7094d8..342f9f04b 100644
--- a/src/main/resources/assets/opencomputers/lua/rom/bin/sh.lua
+++ b/src/main/resources/assets/opencomputers/lua/rom/bin/sh.lua
@@ -121,7 +121,7 @@ if #args == 0 and (io.input() == io.stdin or options.i) and not options.c then
       elseif command ~= "" then
         local result, reason = execute(command)
         if not result then
-          io.stderr:write(reason .. "\n")
+          io.stderr:write((tostring(reason) or "unknown error").. "\n")
         elseif term.getCursor() > 1 then
           term.write("\n")
         end
diff --git a/src/main/resources/assets/opencomputers/lua/rom/init.lua b/src/main/resources/assets/opencomputers/lua/rom/init.lua
index 48cc1be29..99afa57f3 100644
--- a/src/main/resources/assets/opencomputers/lua/rom/init.lua
+++ b/src/main/resources/assets/opencomputers/lua/rom/init.lua
@@ -13,8 +13,9 @@ while true do
   io.write(_OSVERSION .. " (" .. math.floor(computer.totalMemory() / 1024) .. "k RAM)\n")
   local result, reason = os.execute(os.getenv("SHELL") .. " -")
   if not result then
-    io.stderr:write((reason or "unknown error") .. "\n")
+    io.stderr:write((tostring(reason) or "unknown error") .. "\n")
     print("Press any key to continue.")
+    os.sleep(0.5)
     event.pull("key")
   end
 end
\ No newline at end of file

From 65fb648cf9884cd855e2a9a216ffeff7552c1f83 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Thu, 27 Feb 2014 11:11:47 +0100
Subject: [PATCH 12/12] reduced hologram network footprint and sending updates
 to clients more frequently

---
 .../java/li/cil/oc/client/PacketHandler.scala | 21 ++++++++--
 .../tileentity/HologramRenderer.scala         |  4 ++
 .../java/li/cil/oc/common/PacketBuilder.scala | 38 ++++++++++++++++---
 .../java/li/cil/oc/common/PacketHandler.scala | 10 +++--
 .../java/li/cil/oc/common/PacketType.scala    |  1 +
 .../cil/oc/common/tileentity/Hologram.scala   | 38 +++++++++++++++----
 .../java/li/cil/oc/server/PacketSender.scala  | 24 +++++++++---
 7 files changed, 109 insertions(+), 27 deletions(-)

diff --git a/src/main/java/li/cil/oc/client/PacketHandler.scala b/src/main/java/li/cil/oc/client/PacketHandler.scala
index 28b8a04a6..97ce2beaf 100644
--- a/src/main/java/li/cil/oc/client/PacketHandler.scala
+++ b/src/main/java/li/cil/oc/client/PacketHandler.scala
@@ -26,6 +26,7 @@ class PacketHandler extends CommonPacketHandler {
       case PacketType.ChargerState => onChargerState(p)
       case PacketType.ComputerState => onComputerState(p)
       case PacketType.ComputerUserList => onComputerUserList(p)
+      case PacketType.HologramClear => onHologramClear(p)
       case PacketType.HologramScale => onHologramScale(p)
       case PacketType.HologramSet => onHologramSet(p)
       case PacketType.PowerState => onPowerState(p)
@@ -102,6 +103,14 @@ class PacketHandler extends CommonPacketHandler {
       case _ => // Invalid packet.
     }
 
+  def onHologramClear(p: PacketParser) =
+    p.readTileEntity[Hologram]() match {
+      case Some(t) =>
+        for (i <- 0 until t.volume.length) t.volume(i) = 0
+        t.dirty = true
+      case _ => // Invalid packet.
+    }
+
   def onHologramScale(p: PacketParser) =
     p.readTileEntity[Hologram]() match {
       case Some(t) =>
@@ -113,10 +122,14 @@ class PacketHandler extends CommonPacketHandler {
   def onHologramSet(p: PacketParser) =
     p.readTileEntity[Hologram]() match {
       case Some(t) =>
-        val length = p.readInt()
-        val count = math.max(0, math.min(length, t.volume.length))
-        for (i <- 0 until count) {
-          t.volume(i) = p.readInt()
+        val fromX = p.readByte(): Int
+        val untilX = p.readByte(): Int
+        val fromZ = p.readByte(): Int
+        val untilZ = p.readByte(): Int
+        for (x <- fromX until untilX) {
+          for (z <- fromZ until untilZ) {
+            t.volume(x + z * t.width) = p.readInt()
+          }
         }
         t.dirty = true
       case _ => // Invalid packet.
diff --git a/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala b/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
index da5692247..bcf374af9 100644
--- a/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
+++ b/src/main/java/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
@@ -43,6 +43,9 @@ object HologramRenderer extends TileEntitySpecialRenderer with Callable[Int] wit
       GL11.glTranslated(random.nextGaussian() * 0.01, random.nextGaussian() * 0.01, random.nextGaussian() * 0.01)
     }
 
+    // We do two passes here to avoid weird transparency effects: in the first
+    // pass we find the front-most fragment, in the second we actually draw it.
+    // TODO proper transparency shader? depth peeling e.g.
     GL11.glColorMask(false, false, false, false)
     val list = cache.get(hologram, this)
     compileOrDraw(list)
@@ -71,6 +74,7 @@ object HologramRenderer extends TileEntitySpecialRenderer with Callable[Int] wit
     t.startDrawingQuads()
     t.setColorRGBA_F(1, 1, 1, 0.5f)
 
+    // TODO merge quads for better rendering performance
     val s = 1f / 16f * hologram.scale
     for (hx <- 0 until hologram.width) {
       val wx = hx * s
diff --git a/src/main/java/li/cil/oc/common/PacketBuilder.scala b/src/main/java/li/cil/oc/common/PacketBuilder.scala
index 6c0f0f86f..09ac6943b 100644
--- a/src/main/java/li/cil/oc/common/PacketBuilder.scala
+++ b/src/main/java/li/cil/oc/common/PacketBuilder.scala
@@ -3,8 +3,8 @@ package li.cil.oc.common
 import cpw.mods.fml.common.FMLCommonHandler
 import cpw.mods.fml.common.network.PacketDispatcher
 import cpw.mods.fml.common.network.Player
-import java.io.ByteArrayOutputStream
-import java.io.DataOutputStream
+import java.io.{OutputStream, ByteArrayOutputStream, DataOutputStream}
+import java.util.zip.GZIPOutputStream
 import li.cil.oc.common.tileentity.TileEntity
 import net.minecraft.entity.player.EntityPlayerMP
 import net.minecraft.item.ItemStack
@@ -14,9 +14,8 @@ import net.minecraft.world.World
 import net.minecraftforge.common.ForgeDirection
 import scala.collection.convert.WrapAsScala._
 
-class PacketBuilder(packetType: PacketType.Value, private val stream: ByteArrayOutputStream = new ByteArrayOutputStream) extends DataOutputStream(stream) {
-  writeByte(packetType.id)
-
+// Necessary to keep track of the GZIP stream.
+abstract class PacketBuilderBase[T <: OutputStream](protected val stream: T) extends DataOutputStream(stream) {
   def writeTileEntity(t: TileEntity) = {
     writeInt(t.world.provider.dimensionId)
     writeInt(t.x)
@@ -57,7 +56,13 @@ class PacketBuilder(packetType: PacketType.Value, private val stream: ByteArrayO
 
   def sendToServer() = PacketDispatcher.sendPacketToServer(packet)
 
-  private def packet = {
+  protected def packet: Packet250CustomPayload
+}
+
+class PacketBuilder(packetType: PacketType.Value) extends PacketBuilderBase(PacketBuilder.newData(compressed = false)) {
+  writeByte(packetType.id)
+
+  override protected def packet = {
     val p = new Packet250CustomPayload
     p.channel = "OpenComp"
     p.data = stream.toByteArray
@@ -65,3 +70,24 @@ class PacketBuilder(packetType: PacketType.Value, private val stream: ByteArrayO
     p
   }
 }
+
+class CompressedPacketBuilder(packetType: PacketType.Value, private val data: ByteArrayOutputStream = PacketBuilder.newData(compressed = true)) extends PacketBuilderBase(new GZIPOutputStream(data)) {
+  writeByte(packetType.id)
+
+  override protected def packet = {
+    stream.finish()
+    val p = new Packet250CustomPayload
+    p.channel = "OpenComp"
+    p.data = data.toByteArray
+    p.length = data.size
+    p
+  }
+}
+
+object PacketBuilder {
+  def newData(compressed: Boolean) = {
+    val data = new ByteArrayOutputStream
+    data.write(if (compressed) 1 else 0)
+    data
+  }
+}
\ No newline at end of file
diff --git a/src/main/java/li/cil/oc/common/PacketHandler.scala b/src/main/java/li/cil/oc/common/PacketHandler.scala
index 2c103bef6..e3340a117 100644
--- a/src/main/java/li/cil/oc/common/PacketHandler.scala
+++ b/src/main/java/li/cil/oc/common/PacketHandler.scala
@@ -2,9 +2,9 @@ package li.cil.oc.common
 
 import cpw.mods.fml.common.network.IPacketHandler
 import cpw.mods.fml.common.network.Player
-import java.io.ByteArrayInputStream
-import java.io.DataInputStream
+import java.io.{InputStream, ByteArrayInputStream, DataInputStream}
 import java.util.logging.Level
+import java.util.zip.GZIPInputStream
 import li.cil.oc.{Blocks, OpenComputers}
 import net.minecraft.item.ItemStack
 import net.minecraft.nbt.CompressedStreamTools
@@ -22,7 +22,9 @@ abstract class PacketHandler extends IPacketHandler {
     // malicious client, in which case we don't want to allow it to kill the
     // server like this). Just spam the log a bit... ;)
     try {
-      dispatch(new PacketParser(packet, player))
+      val stream = new ByteArrayInputStream(packet.data)
+      if (stream.read() == 0) dispatch(new PacketParser(stream, player))
+      else dispatch(new PacketParser(new GZIPInputStream(stream), player))
     } catch {
       case e: Throwable =>
         OpenComputers.log.log(Level.WARNING, "Received a badly formatted packet.", e)
@@ -40,7 +42,7 @@ abstract class PacketHandler extends IPacketHandler {
 
   protected def dispatch(p: PacketParser)
 
-  protected class PacketParser(packet: Packet250CustomPayload, val player: Player) extends DataInputStream(new ByteArrayInputStream(packet.data)) {
+  protected class PacketParser(stream: InputStream, val player: Player) extends DataInputStream(stream) {
     val packetType = PacketType(readByte())
 
     def getTileEntity[T: ClassTag](dimension: Int, x: Int, y: Int, z: Int): Option[T] = {
diff --git a/src/main/java/li/cil/oc/common/PacketType.scala b/src/main/java/li/cil/oc/common/PacketType.scala
index 059b3d2f1..74f1d21ce 100644
--- a/src/main/java/li/cil/oc/common/PacketType.scala
+++ b/src/main/java/li/cil/oc/common/PacketType.scala
@@ -8,6 +8,7 @@ object PacketType extends Enumeration {
   ChargerState,
   ComputerState,
   ComputerUserList,
+  HologramClear,
   HologramScale,
   HologramSet,
   PowerState,
diff --git a/src/main/java/li/cil/oc/common/tileentity/Hologram.scala b/src/main/java/li/cil/oc/common/tileentity/Hologram.scala
index f5f24e323..28318ade6 100644
--- a/src/main/java/li/cil/oc/common/tileentity/Hologram.scala
+++ b/src/main/java/li/cil/oc/common/tileentity/Hologram.scala
@@ -29,11 +29,35 @@ class Hologram extends Environment with SidedEnvironment {
   // Whether we need to send an update packet/recompile our display list.
   var dirty = false
 
+  // Interval of dirty columns.
+  var dirtyFromX = Int.MaxValue
+  var dirtyUntilX = -1
+  var dirtyFromZ = Int.MaxValue
+  var dirtyUntilZ = -1
+
   // Time to wait before sending another update packet.
-  var cooldown = 0
+  var cooldown = 5
 
   var hasPower = true
 
+  def setDirty(x: Int, z: Int) {
+    dirty = true
+    dirtyFromX = math.min(dirtyFromX, x)
+    dirtyUntilX = math.max(dirtyUntilX, x + 1)
+    dirtyFromZ = math.min(dirtyFromZ, z)
+    dirtyUntilZ = math.max(dirtyUntilZ, z + 1)
+    litRatio = -1
+  }
+
+  def resetDirtyFlag() {
+    dirty = false
+    dirtyFromX = Int.MaxValue
+    dirtyUntilX = -1
+    dirtyFromZ = Int.MaxValue
+    dirtyUntilZ = -1
+    cooldown = 5
+  }
+
   // ----------------------------------------------------------------------- //
 
   override def canConnect(side: ForgeDirection) = side != ForgeDirection.UP
@@ -45,7 +69,8 @@ class Hologram extends Environment with SidedEnvironment {
   @Callback(doc = """function() -- Clears the hologram.""")
   def clear(computer: Context, args: Arguments): Array[AnyRef] = this.synchronized {
     for (i <- 0 until volume.length) volume(i) = 0
-    dirty = true
+    ServerPacketSender.sendHologramClear(this)
+    resetDirtyFlag()
     litRatio = 0
     null
   }
@@ -63,8 +88,7 @@ class Hologram extends Environment with SidedEnvironment {
     val z = args.checkInteger(1) - 1
     val value = args.checkInteger(2)
     volume(x + z * width) = value
-    dirty = true
-    litRatio = -1
+    setDirty(x, z)
     null
   }
 
@@ -76,8 +100,7 @@ class Hologram extends Environment with SidedEnvironment {
     // Bit shifts in the JVM only use the lowest five bits... so we have to
     // manually check the height, to avoid the shift being a no-op.
     volume(x + z * width) = if (height > 0) 0xFFFFFFFF >>> (32 - height) else 0
-    dirty = true
-    litRatio = -1
+    setDirty(x, z)
     null
   }
 
@@ -101,9 +124,8 @@ class Hologram extends Environment with SidedEnvironment {
       if (dirty) {
         cooldown -= 1
         if (cooldown <= 0) {
-          dirty = false
-          cooldown = 10
           ServerPacketSender.sendHologramSet(this)
+          resetDirtyFlag()
         }
       }
       if (litRatio < 0) {
diff --git a/src/main/java/li/cil/oc/server/PacketSender.scala b/src/main/java/li/cil/oc/server/PacketSender.scala
index 55dc419b3..077e325dc 100644
--- a/src/main/java/li/cil/oc/server/PacketSender.scala
+++ b/src/main/java/li/cil/oc/server/PacketSender.scala
@@ -1,9 +1,8 @@
 package li.cil.oc.server
 
 import li.cil.oc.common
-import li.cil.oc.common.PacketBuilder
-import li.cil.oc.common.PacketType
 import li.cil.oc.common.tileentity._
+import li.cil.oc.common.{CompressedPacketBuilder, PacketBuilder, PacketType}
 import li.cil.oc.util.PackedColor
 import net.minecraft.entity.player.EntityPlayerMP
 import net.minecraft.item.ItemStack
@@ -55,6 +54,14 @@ object PacketSender {
     pb.sendToNearbyPlayers(t)
   }
 
+  def sendHologramClear(t: Hologram) {
+    val pb = new PacketBuilder(PacketType.HologramClear)
+
+    pb.writeTileEntity(t)
+
+    pb.sendToNearbyPlayers(t)
+  }
+
   def sendHologramScale(t: Hologram) {
     val pb = new PacketBuilder(PacketType.HologramScale)
 
@@ -65,11 +72,18 @@ object PacketSender {
   }
 
   def sendHologramSet(t: Hologram) {
-    val pb = new PacketBuilder(PacketType.HologramSet)
+    val pb = new CompressedPacketBuilder(PacketType.HologramSet)
 
     pb.writeTileEntity(t)
-    pb.writeInt(t.volume.length)
-    t.volume.foreach(pb.writeInt)
+    pb.writeByte(t.dirtyFromX)
+    pb.writeByte(t.dirtyUntilX)
+    pb.writeByte(t.dirtyFromZ)
+    pb.writeByte(t.dirtyUntilZ)
+    for (x <- t.dirtyFromX until t.dirtyUntilX) {
+      for (z <- t.dirtyFromZ until t.dirtyUntilZ) {
+        pb.writeInt(t.volume(x + z * t.width))
+      }
+    }
 
     pb.sendToNearbyPlayers(t)
   }