From 4dadff6e6234a83b612d8ab5fbf7b0cf23b42890 Mon Sep 17 00:00:00 2001
From: hneemann <helmut.neemann@arcor.de>
Date: Tue, 29 Aug 2017 22:17:25 +0200
Subject: [PATCH] modifies data bit only if necessary.

---
 .../gui/components/CircuitComponent.java      |  4 ++-
 .../modification/ModifySetBits.java           | 26 +++++++++++++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/src/main/java/de/neemann/digital/gui/components/CircuitComponent.java b/src/main/java/de/neemann/digital/gui/components/CircuitComponent.java
index fa1ba975f..0c89b7f48 100644
--- a/src/main/java/de/neemann/digital/gui/components/CircuitComponent.java
+++ b/src/main/java/de/neemann/digital/gui/components/CircuitComponent.java
@@ -1022,7 +1022,9 @@ public class CircuitComponent extends JComponent implements Circuit.ChangedListe
                             int bits = Integer.decode(num);
                             Vector c1 = mouseControllerSelect.corner1;
                             Vector c2 = mouseControllerSelect.corner2;
-                            modify(new ModifySetBits(c1, c2, bits));
+                            ModifySetBits modifySetBits = new ModifySetBits(c1, c2, bits);
+                            if (modifySetBits.isSomethingToDo(circuit, library))
+                                modify(modifySetBits);
                             removeHighLighted();
                             mouseNormal.activate();
                         } catch (NumberFormatException ex) {
diff --git a/src/main/java/de/neemann/digital/gui/components/modification/ModifySetBits.java b/src/main/java/de/neemann/digital/gui/components/modification/ModifySetBits.java
index b32d96160..e5320ce00 100644
--- a/src/main/java/de/neemann/digital/gui/components/modification/ModifySetBits.java
+++ b/src/main/java/de/neemann/digital/gui/components/modification/ModifySetBits.java
@@ -54,6 +54,32 @@ public class ModifySetBits implements Modification {
         circuit.modified();
     }
 
+    /**
+     * Checks if there are relevant elements in the rectangle
+     *
+     * @param circuit the circuit
+     * @param library the library
+     * @return true if there are components with a bits attribute
+     */
+    public boolean isSomethingToDo(Circuit circuit, ElementLibrary library) {
+        ArrayList<Movable> list = circuit.getElementsToMove(min, max);
+        for (Movable m : list)
+            if (m instanceof VisualElement) {
+                VisualElement ve = (VisualElement) m;
+                try {
+                    ElementTypeDescription td = library.getElementType(ve.getElementName());
+                    if (td != null) {
+                        if (td.getAttributeList().contains(Keys.BITS))
+                            if (ve.getElementAttributes().get(Keys.BITS) != bits)
+                                return true;
+                    }
+                } catch (ElementNotFoundException e) {
+                    e.printStackTrace();
+                }
+            }
+        return false;
+    }
+
     @Override
     public String toString() {
         return Lang.get("mod_set_N_BitsToSelection", bits);