From ad4359f2dd6743f4a807789512e0fdc186bcf64c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Wed, 1 Jan 2014 17:50:46 +0100
Subject: [PATCH] making `term.read` check for changes to the term's cursor
 position between events, to make it less problematic to display text via
 `print` or `term.write` when there's a read active (e.g. because we're in the
 shell or so but we want to print something from an event listener, such as a
 timer)

---
 assets/opencomputers/lua/rom/lib/term.lua           |  6 ++++++
 .../oc/client/renderer/MonospaceFontRenderer.scala  |  4 ++--
 .../client/renderer/tileentity/ScreenRenderer.scala | 13 +++++++++----
 3 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/assets/opencomputers/lua/rom/lib/term.lua b/assets/opencomputers/lua/rom/lib/term.lua
index 6782edeb6..f16e3c55c 100644
--- a/assets/opencomputers/lua/rom/lib/term.lua
+++ b/assets/opencomputers/lua/rom/lib/term.lua
@@ -284,11 +284,17 @@ function term.read(history)
 
   term.setCursorBlink(true)
   while term.isAvailable() do
+    local ocx, ocy = getCursor()
     local ok, name, address, charOrValue, code = pcall(event.pull)
     if not ok then
       cleanup()
       error("interrupted", 0)
     end
+    local ncx, ncy = getCursor()
+    if ocx ~= ncx or ocy ~= ncy then
+      cleanup()
+      return "" -- soft fail the read if someone messes with the term
+    end
     if term.isAvailable() and -- may have changed since pull
        type(address) == "string" and
        component.isPrimary(address)
diff --git a/li/cil/oc/client/renderer/MonospaceFontRenderer.scala b/li/cil/oc/client/renderer/MonospaceFontRenderer.scala
index 32ad3448e..d4cce67b1 100644
--- a/li/cil/oc/client/renderer/MonospaceFontRenderer.scala
+++ b/li/cil/oc/client/renderer/MonospaceFontRenderer.scala
@@ -23,10 +23,10 @@ object MonospaceFontRenderer {
   val fontWidth = 5
   val fontHeight = 9
 
-  def drawString(x: Int, y: Int, value: Array[Char], color: Array[Short], depth: PackedColor.Depth.Value) = instance match {
+  def drawString(x: Int, y: Int, value: Array[Char], color: Array[Short], depth: PackedColor.Depth.Value) = this.synchronized(instance match {
     case None => OpenComputers.log.warning("Trying to render string with uninitialized MonospaceFontRenderer.")
     case Some(renderer) => renderer.drawString(x, y, value, color, depth)
-  }
+  })
 
   private class Renderer(private val textureManager: TextureManager) {
     /** Display lists, one per char (renders quad with char's uv coords). */
diff --git a/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala b/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala
index 5c05e46c3..929260841 100644
--- a/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala
+++ b/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala
@@ -132,14 +132,17 @@ object ScreenRenderer extends TileEntitySpecialRenderer with Callable[Int] with
     }
   }
 
-  private def compileOrDraw(list: Int) = if (screen.bufferIsDirty && !RenderState.compilingDisplayList) {
-    screen.bufferIsDirty = false
+  private def compileOrDraw(list: Int) = if (screen.bufferIsDirty) {
     val sx = screen.width
     val sy = screen.height
     val tw = sx * 16f
     val th = sy * 16f
 
-    GL11.glNewList(list, GL11.GL_COMPILE_AND_EXECUTE)
+    val doCompile = !RenderState.compilingDisplayList
+    if (doCompile) {
+      screen.bufferIsDirty = false
+      GL11.glNewList(list, GL11.GL_COMPILE_AND_EXECUTE)
+    }
 
     transform()
 
@@ -178,7 +181,9 @@ object ScreenRenderer extends TileEntitySpecialRenderer with Callable[Int] with
       MonospaceFontRenderer.drawString(0, i * MonospaceFontRenderer.fontHeight, line, color, screen.buffer.depth)
     }
 
-    GL11.glEndList()
+    if (doCompile) {
+      GL11.glEndList()
+    }
 
     true
   }