Added focus-follows-mouse logic to kOS for CTB

Author: Dunbaratu

CONTRIBUTING.md

@@ -215,11 +215,20 @@ Setting Up Your Environment
 
         3. Make sure your installation of KSP has LinuxGuruGamer's ClivkThroughBlocker
            mod installed.  kOS now needs it in order to compile.  After it is
-           installed, create a reference for it in your kOS project's References
-           like so:
+           installed, copy its DLL file into Resources/ from your GameData folder.
+
+           Copy This file:
 
                * $KSP/GameData/00_ClickThroughBlocker/Plugins/ClickThroughBlocker.dll
 
+           To here:
+
+               * Resources/
+
+           Then *make a Reference to Resoruces/ClickThroughBlocker.dll in your kOS project
+           file*.  This is needed for it to let you compile parts of kOS that use classes
+           from ClickThroughBlocker.
+
 	4. If you do not have a copy of KSP locally, you may
 	  download dummy assemblies at https://github.com/KSP-KOS/KSP_LIB
 

src/kOS/Screen/KOSManagedWindow.cs

@@ -231,14 +231,13 @@ public bool IsOpen
         }
 
         /// <summary>
-        /// Pass in the absolute GUI screen location of a mouse click to decide whether
-        /// or not this widget gets keyboard focus because of that click.
-        /// (Clicking outside the window takes focus away.  Clicking inside
-        /// the window gives focus to the window and brings it to the front.)
-        /// </summary>
+        /// Pass in the absolute GUI screen location of the mouse to decide whether
+        /// or not this window gets keyboard focus because of that position.
+        /// (If you want focus-follows-mouse logic, call this every Update().  If you
+        /// want click-to-focus logic, only call this in Update()s where a click just happened.)
         /// <param name="absMousePos">Absolute position of mouse on whole screen</param>
         /// <returns>True if the window got focused, false if it didn't.</returns>
-        public bool FocusClickLocationCheck(Vector2 absMousePos)
+        public bool FocusMouseLocationCheck(Vector2 absMousePos)
         {
             bool wasInside = false;
             if (IsInsideMyExposedPortion(absMousePos))
@@ -295,42 +294,55 @@ public bool IsInsideMyExposedPortion(Vector2 posAbsolute)
 
         /// <summary>
         /// When you subclass KOSManagedWindow, make sure that you call this
-        /// from inside your Update.  It does not use OnGUI because of the fact
-        /// that the OnGUI event handler is broken - it only sends MouseDown 
-        /// and MouseUp events when the mouse is OUTSIDE the window, which is
-        /// utterly backward, and it's hard to work out how to fix this,
-        /// given how badly documented the Unity GUI API is.  If anyone who
-        /// actually understands the Unity GUI system wants to fix this,
-        /// please feel free to do so.
+        /// from inside your Update() to check for focus change on the window.
+        /// Calling this will maybe call GetFocus() or LoseFocus() depending on
+        /// what the mouse is doing.
+        /// Note, you call this during *Update()*, NOT the OnGUI() call.
+        /// It does not use OnGUI() because the raw mousebutton state it
+        /// needs to see can get consumed and wiped by Unity's IMGUI widgets
+        /// before application code like this can see it.
         /// </summary>
-        /// <returns>True if there was a mouseclick within this window.</returns>
-        public bool UpdateLogic()
+        public void UpdateLogic()
         {
-            if (!IsOpen) return false;
+            if (!IsOpen) return;
 
             // Input.mousePosition, unlike Event.current.MousePosition, puts the origin at the
             // lower-left instead of upper-left of the screen, thus the subtraction in the y coord below:
             mousePosAbsolute = new Vector2( Input.mousePosition.x, UnityEngine.Screen.height - Input.mousePosition.y);
 
             // Mouse coord within the window, rather than within the screen.
             mousePosRelative = new Vector2( mousePosAbsolute.x - windowRect.xMin, mousePosAbsolute.y - windowRect.yMin);
-    
-            bool clickUp = false;
+
+            // Could maybe cache the CustomParams call once up front to get a reference to the CTB instance, then only
+            // repeat the ".focusFollowsclick" part each update.  The reason that's not being done here is that I
+            // noticed ClickThroughBlocker's OWN code always does it like this, and for all I know there might be
+            // an important reason.  It always gets this value by using the fully qualified long chain you see
+            // here, starting from HighLogic, each update. :
+            bool clickToFocus = HighLogic.CurrentGame.Parameters.CustomParams<ClickThroughFix.CTB>().focusFollowsclick;
+
             if (Input.GetMouseButtonDown(0))
             {
                 mouseButtonDownPosAbsolute = mousePosAbsolute;
                 mouseButtonDownPosRelative = mousePosRelative;
             }
-    
-            if (Input.GetMouseButtonUp(0))
+
+            bool mousePositionCanSetFocus = !(clickToFocus); // Always true in focus-follows-mouse mode
+
+            if (clickToFocus)
             {
-                clickUp = true;
-                if (Vector2.Distance(mousePosAbsolute,mouseButtonDownPosAbsolute) <= dragTolerance)
+                if (Input.GetMouseButtonUp(0))
                 {
-                    FocusClickLocationCheck(mousePosAbsolute);
+                    if (Vector2.Distance(mousePosAbsolute, mouseButtonDownPosAbsolute) <= dragTolerance)
+                    {
+                        mousePositionCanSetFocus = true;
+                    }
                 }
             }
-            return IsInsideMyExposedPortion(mousePosAbsolute) && clickUp;
+
+            if (mousePositionCanSetFocus)
+            {
+                FocusMouseLocationCheck(mousePosAbsolute);
+            }
         }
     }
 }

src/kOS/kOS.csproj

@@ -37,7 +37,8 @@
     <Reference Include="Assembly-CSharp-firstpass">
       <HintPath>..\..\Resources\Assembly-CSharp-firstpass.dll</HintPath>
     </Reference>
-    <Reference Include="ClickThroughBlocker">
+    <Reference Include="ClickThroughBlocker, Version=0.1.9.5, Culture=neutral, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
       <HintPath>..\..\Resources\ClickThroughBlocker.dll</HintPath>
     </Reference>
     <Reference Include="ICSharpCode.SharpZipLib">