From fdcdb2c7c55822e3a0866baae8ab97e7de8ef143 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20N=C3=BCcke?= <florian@nuecke.de>
Date: Tue, 9 Jun 2015 21:52:38 +0200
Subject: [PATCH] Should fix incorrect coordinates in mouse scroll event in
 scaled GUIs, closing #1212.

---
 .../scala/li/cil/oc/client/gui/Screen.scala   | 33 ++++++++++---------
 1 file changed, 17 insertions(+), 16 deletions(-)

diff --git a/src/main/scala/li/cil/oc/client/gui/Screen.scala b/src/main/scala/li/cil/oc/client/gui/Screen.scala
index d6620f499..6966ada48 100644
--- a/src/main/scala/li/cil/oc/client/gui/Screen.scala
+++ b/src/main/scala/li/cil/oc/client/gui/Screen.scala
@@ -27,13 +27,11 @@ class Screen(val buffer: api.component.TextBuffer, val hasMouse: Boolean, val ha
     if (hasMouse && Mouse.hasWheel && Mouse.getEventDWheel != 0) {
       val mouseX = Mouse.getEventX * width / mc.displayWidth
       val mouseY = height - Mouse.getEventY * height / mc.displayHeight - 1
-      val bx = (mouseX - x - bufferMargin) / TextBufferRenderCache.renderer.charRenderWidth.toDouble
-      val by = (mouseY - y - bufferMargin) / TextBufferRenderCache.renderer.charRenderHeight.toDouble
-      val bw = buffer.getWidth
-      val bh = buffer.getHeight
-      if (bx >= 0 && by >= 0 && bx < bw && by < bh) {
-        val scroll = math.signum(Mouse.getEventDWheel)
-        buffer.mouseScroll(bx, by, scroll, null)
+      toBufferCoordinates(mouseX, mouseY) match {
+        case Some((bx, by)) =>
+          val scroll = math.signum(Mouse.getEventDWheel)
+          buffer.mouseScroll(bx, by, scroll, null)
+        case _ => // Ignore when out of bounds.
       }
     }
   }
@@ -60,15 +58,9 @@ class Screen(val buffer: api.component.TextBuffer, val hasMouse: Boolean, val ha
     super.mouseMovedOrUp(mouseX, mouseY, button)
     if (hasMouse && button >= 0) {
       if (didDrag) {
-        val bx = (mouseX - x - bufferMargin) / scale / TextBufferRenderCache.renderer.charRenderWidth
-        val by = (mouseY - y - bufferMargin) / scale / TextBufferRenderCache.renderer.charRenderHeight
-        val bw = buffer.getWidth
-        val bh = buffer.getHeight
-        if (bx >= 0 && by >= 0 && bx < bw && by < bh) {
-          buffer.mouseUp(bx, by, button, null)
-        }
-        else {
-          buffer.mouseUp(-1.0, -1.0, button, null)
+        toBufferCoordinates(mouseX, mouseY) match {
+          case Some((bx, by)) => buffer.mouseUp(bx, by, button, null)
+          case _ => buffer.mouseUp(-1.0, -1.0, button, null)
         }
       }
       didDrag = false
@@ -77,6 +69,15 @@ class Screen(val buffer: api.component.TextBuffer, val hasMouse: Boolean, val ha
     }
   }
 
+  private def toBufferCoordinates(mouseX: Int, mouseY: Int): Option[(Double, Double)] = {
+    val bx = (mouseX - x - bufferMargin) / scale / TextBufferRenderCache.renderer.charRenderWidth
+    val by = (mouseY - y - bufferMargin) / scale / TextBufferRenderCache.renderer.charRenderHeight
+    val bw = buffer.getWidth
+    val bh = buffer.getHeight
+    if (bx >= 0 && by >= 0 && bx < bw && by < bh) Some((bx, by))
+    else None
+  }
+
   private def clickOrDrag(mouseX: Int, mouseY: Int, button: Int) {
     val bx = (mouseX - x - bufferMargin) / scale / TextBufferRenderCache.renderer.charRenderWidth
     val by = (mouseY - y - bufferMargin) / scale / TextBufferRenderCache.renderer.charRenderHeight