Update jump heights only when necessary.

This method uses signaling (through a boolean) and I feel like it's
extremely hacky, but I tested this and it (kind of?) works.
Unfortunately I found this to potentially lag when resizing.

I am not sure if this is guaranteed to work (as in, produce correct
behaviour) or not, but to my understanding only LogicDialog uses LCanvas
(grep out "LCanvas\|canvas" and see) so it will most likely work?

I tested this and accidentally found an unrelated issue related to
LCanvas.maxJumpsDrawn, but I hope this will be fixed in the near future.

core/src/mindustry/logic/LCanvas.java

@@ -159,6 +159,7 @@ public class LCanvas extends Table{
             st.setupUI();
         }
 
+        this.statements.updateJumpHeights = true;
         this.statements.layout();
     }
 
@@ -202,6 +203,7 @@ public class LCanvas extends Table{
         boolean invalidated;
         public Group jumps = new WidgetGroup();
         private Seq<JumpCurve> processedJumps = new Seq<JumpCurve>();
+        public boolean updateJumpHeights = true;
 
         {
             setTransform(true);
@@ -257,7 +259,10 @@ public class LCanvas extends Table{
                 }
             }
 
-            if(dynamicJumpHeights) setJumpHeights();
+            if(dynamicJumpHeights){
+                if(updateJumpHeights) setJumpHeights();
+                updateJumpHeights = false;
+            }
 
             if(parent != null) parent.invalidateHierarchy();//don't invalid self
 
@@ -394,6 +399,7 @@ public class LCanvas extends Table{
                 dragging = null;
             }
 
+            updateJumpHeights = true;
             layout();
         }
     }
@@ -430,6 +436,7 @@ public class LCanvas extends Table{
                 t.button(Icon.cancel, Styles.logici, () -> {
                     remove();
                     dragging = null;
+                    statements.updateJumpHeights = true;
                     statements.layout();
                 }).size(24f);
 
@@ -449,6 +456,7 @@ public class LCanvas extends Table{
                         lasty = v.y;
                         dragging = StatementElem.this;
                         toFront();
+                        statements.updateJumpHeights = true;
                         statements.layout();
                         return true;
                     }
@@ -506,6 +514,7 @@ public class LCanvas extends Table{
                 statements.layout();
                 copy.elem = s;
                 copy.setupUI();
+                statements.updateJumpHeights = true;
             }
         }
 
@@ -549,6 +558,7 @@ public class LCanvas extends Table{
                     setter.get(null);
                     mx = x;
                     my = y;
+                    canvas.statements.updateJumpHeights = true;
                     return true;
                 }
 
@@ -569,6 +579,7 @@ public class LCanvas extends Table{
                         setter.get(null);
                     }
                     selecting = false;
+                    canvas.statements.updateJumpHeights = true;
                 }
             });
 

core/src/mindustry/logic/LogicDialog.java

@@ -256,6 +256,8 @@ public class LogicDialog extends BaseDialog{
             dialog.addCloseButton();
             dialog.show();
         }).disabled(t -> canvas.statements.getChildren().size >= LExecutor.maxInstructions);
+        
+        Core.app.post(canvas::rebuild);
     }
 
     public void show(String code, LExecutor executor, boolean privileged, Cons<String> modified){