added possible element wobble

Demos/UiDemo.cs

@@ -134,6 +134,13 @@ namespace Demos {
             root.AddChild(new Paragraph(Anchor.AutoLeft, 1, paragraph => "Slider is at " + (slider.CurrentValue * 100).Floor() + "%") {PositionOffset = new Vector2(0, 1)});
             root.AddChild(slider);
 
+            // This button uses a coroutine from my Coroutine NuGet package (which is included with MLEM.Startup)
+            // but the important thing it does is change its visual scale and offset (check the method below for more info)
+            root.AddChild(new Button(Anchor.AutoCenter, new Vector2(0.5F, 10), "Wobble", "This button wobbles around visually when clicked, but this doesn't affect its actual size and positioning") {
+                OnClicked = (element, button) => CoroutineHandler.Start(this.WobbleButton(element)),
+                PositionOffset = new Vector2(0, 1)
+            });
+
             // Below are some querying examples that help you find certain elements easily
 
             var children = root.GetChildren();
@@ -152,6 +159,23 @@ namespace Demos {
             Console.WriteLine($"The root has {autoWidthChildren.Count()} auto-width children, {autoWidthButtons.Count()} of which are buttons");
         }
 
+        // This method is used by the wobbling button (see above)
+        // Note that this particular example makes use of the Coroutine package
+        private IEnumerator<Wait> WobbleButton(Element button) {
+            var counter = 0F;
+            while (counter < 10) {
+                // The imporant bit is that it changes its added display scale and offset, allowing the button to still maintain the
+                // correct position and scaling for both anchoring and interacting purposes, but to show any kind of animation visually
+                // This could be useful, for example, to create a little feedback effect to clicking it where it changes size for a second
+                button.AddedDisplayScale = new Vector2((float) Math.Sin(counter));
+                button.AddedDisplayOffset = new Vector2((float) Math.Sin(counter / 2) * 4, 0);
+                counter += 0.1F;
+                yield return new WaitSeconds(0.01F);
+            }
+            button.AddedDisplayScale = Vector2.Zero;
+            button.AddedDisplayOffset = Vector2.Zero;
+        }
+
         protected override void DoDraw(GameTime gameTime) {
             this.GraphicsDevice.Clear(Color.CornflowerBlue);
             base.DoDraw(gameTime);

MLEM.Ui/Elements/Element.cs

@@ -74,6 +74,10 @@ namespace MLEM.Ui.Elements {
             }
         }
         public Point ScaledChildPadding => this.childPadding.Multiply(this.Scale);
+        public Vector2 AddedDisplayOffset;
+        public Point ScaledDisplayOffset => (this.AddedDisplayOffset * this.Scale).ToPoint();
+        public Vector2 AddedDisplayScale;
+        public Point ScaledDisplayScale => (this.AddedDisplayScale * this.Scale).ToPoint();
 
         public MouseClickCallback OnClicked;
         public GenericCallback OnSelected;
@@ -123,7 +127,8 @@ namespace MLEM.Ui.Elements {
         public Rectangle DisplayArea {
             get {
                 var padded = this.Area;
-                padded.Location += this.ScaledPadding;
+                padded.Inflate(this.ScaledDisplayScale.X, this.ScaledDisplayScale.Y);
+                padded.Location += this.ScaledPadding + this.ScaledDisplayOffset;
                 padded.Width -= this.ScaledPadding.X * 2;
                 padded.Height -= this.ScaledPadding.Y * 2;
                 return padded;
@@ -358,23 +363,23 @@ namespace MLEM.Ui.Elements {
 
         public IEnumerable<Element> GetChildren(Func<Element, bool> condition = null, bool regardChildrensChildren = false) {
             foreach (var child in this.Children) {
-                if (condition == null || condition(child))
-                    yield return child;
                 if (regardChildrensChildren) {
                     foreach (var cc in child.GetChildren(condition, true))
                         yield return cc;
                 }
+                if (condition == null || condition(child))
+                    yield return child;
             }
         }
 
         public IEnumerable<T> GetChildren<T>(Func<T, bool> condition = null, bool regardChildrensChildren = false) where T : Element {
             foreach (var child in this.Children) {
-                if (child is T t && (condition == null || condition(t)))
-                    yield return t;
                 if (regardChildrensChildren) {
                     foreach (var cc in child.GetChildren(condition, true))
                         yield return cc;
                 }
+                if (child is T t && (condition == null || condition(t)))
+                    yield return t;
             }
         }