Deselect chunks In rectangle if all selected (#1014)

* Deselect Chunks In Rectangle If All Selected

* update license date

Author: IceSelkie

chunky/src/java/se/llbit/chunky/ui/ChunkMap.java

@@ -256,11 +256,12 @@ protected synchronized void selectWithinRect() {
       int x1 = Math.max(cp0.x, cp1.x);
       int z0 = Math.min(cp0.z, cp1.z);
       int z1 = Math.max(cp0.z, cp1.z);
-      if (ctrlModifier) {
+
+      // If ctrlModifier to deselect, then do deselect
+      // If no ctrlModifier, select chunks
+      // but if they are all already selected, then deselect.
+      if (ctrlModifier || !chunkSelection.selectChunks(mapLoader.getWorld(), x0, z0, x1, z1))
         chunkSelection.deselectChunks(x0, z0, x1, z1);
-      } else {
-        chunkSelection.selectChunks(mapLoader.getWorld(), x0, z0, x1, z1);
-      }
     }
   }
 

chunky/src/java/se/llbit/chunky/world/ChunkSelectionTracker.java

@@ -1,4 +1,5 @@
-/* Copyright (c) 2012 Jesper Öqvist <jesper@llbit.se>
+/* Copyright (c) 2012-2021 Jesper Öqvist <jesper@llbit.se>
+ * Copyright (c) 2012-2021 Chunky contributors
  *
  * This file is part of Chunky.
  *
@@ -140,8 +141,9 @@ public synchronized void selectRegion(World world, int cx, int cz) {
 
   /**
    * Select chunks within rectangle.
+   * @return true if anything was changed, false if no chunks were selected.
    */
-  public synchronized void selectChunks(World world, int cx0, int cz0, int cx1, int cz1) {
+  public synchronized boolean selectChunks(World world, int cx0, int cz0, int cx1, int cz1) {
     boolean selectionChanged = false;
     for (int cx = cx0; cx <= cx1; ++cx) {
       for (int cz = cz0; cz <= cz1; ++cz) {
@@ -156,12 +158,14 @@ public synchronized void selectChunks(World world, int cx0, int cz0, int cx1, in
     if (selectionChanged) {
       notifyChunkSelectionChange();
     }
+    return selectionChanged;
   }
 
   /**
    * Deselect chunks within rectangle.
+   * @return true if anything was changed, false if no chunks were deselected.
    */
-  public synchronized void deselectChunks(int cx0, int cz0, int cx1, int cz1) {
+  public synchronized boolean deselectChunks(int cx0, int cz0, int cx1, int cz1) {
     boolean selectionChanged = false;
     for (int cx = cx0; cx <= cx1; ++cx) {
       for (int cz = cz0; cz <= cz1; ++cz) {
@@ -176,6 +180,7 @@ public synchronized void deselectChunks(int cx0, int cz0, int cx1, int cz1) {
     if (selectionChanged) {
       notifyChunkSelectionChange();
     }
+    return selectionChanged;
   }
 
   /**