diff --git a/Demos/EasingsDemo.cs b/Demos/EasingsDemo.cs
new file mode 100644
index 0000000..94649d0
--- /dev/null
+++ b/Demos/EasingsDemo.cs
@@ -0,0 +1,54 @@
+using System.Linq;
+using System.Reflection;
+using Microsoft.Xna.Framework;
+using Microsoft.Xna.Framework.Graphics;
+using MLEM.Extensions;
+using MLEM.Misc;
+using MLEM.Startup;
+using MLEM.Ui;
+using MLEM.Ui.Elements;
+
+namespace Demos {
+ public class EasingsDemo : Demo {
+
+ private static readonly FieldInfo[] EasingFields = typeof(Easings)
+ .GetFields(BindingFlags.Public | BindingFlags.Static).ToArray();
+ private static readonly Easings.Easing[] Easings = EasingFields
+ .Select(f => (Easings.Easing) f.GetValue(null)).ToArray();
+ private Group group;
+ private int current;
+
+ public EasingsDemo(MlemGame game) : base(game) {
+ }
+
+ public override void LoadContent() {
+ base.LoadContent();
+
+ this.group = new Group(Anchor.TopCenter, Vector2.One) {SetWidthBasedOnChildren = true};
+ this.group.AddChild(new Button(Anchor.AutoCenter, new Vector2(30, 10), "Next") {
+ OnPressed = e => this.current = (this.current + 1) % Easings.Length
+ });
+ this.group.AddChild(new Paragraph(Anchor.AutoCenter, 1, p => EasingFields[this.current].Name, true));
+ this.UiSystem.Get("DemoUi").Element.AddChild(this.group);
+ }
+
+ public override void Clear() {
+ this.group.Parent.RemoveChild(this.group);
+ }
+
+ public override void DoDraw(GameTime time) {
+ this.GraphicsDevice.Clear(Color.CornflowerBlue);
+ base.DoDraw(time);
+
+ this.SpriteBatch.Begin(SpriteSortMode.Deferred, null, SamplerState.PointClamp);
+ var view = this.GraphicsDevice.Viewport;
+ var easing = Easings[this.current].ScaleInput(0, view.Width).ScaleOutput(-view.Height / 3, view.Height / 3);
+ for (var x = 0; x < view.Width; x++) {
+ var area = new RectangleF(x - 2, view.Height / 2 - easing(x) - 2, 4, 4);
+ this.SpriteBatch.Draw(this.SpriteBatch.GetBlankTexture(), area, Color.Green);
+ }
+ this.SpriteBatch.End();
+ }
+
+ }
+}
\ No newline at end of file
diff --git a/Demos/GameImpl.cs b/Demos/GameImpl.cs
index baa3cdf..b123257 100644
--- a/Demos/GameImpl.cs
+++ b/Demos/GameImpl.cs
@@ -24,6 +24,7 @@ namespace Demos {
Demos.Add("Animation and Texture Atlas", ("An example of UniformTextureAtlases, SpriteAnimations and SpriteAnimationGroups", game => new AnimationDemo(game)));
Demos.Add("Auto Tiling", ("A demonstration of the AutoTiling class that MLEM provides", game => new AutoTilingDemo(game)));
Demos.Add("Pathfinding", ("An example of MLEM's A* pathfinding implementation in 2D", game => new PathfindingDemo(game)));
+ Demos.Add("Easings", ("An example of MLEM's Easings class, an adaptation of easings.net", game => new EasingsDemo(game)));
}
public GameImpl() {
diff --git a/MLEM/Misc/Easings.cs b/MLEM/Misc/Easings.cs
new file mode 100644
index 0000000..dad8e04
--- /dev/null
+++ b/MLEM/Misc/Easings.cs
@@ -0,0 +1,110 @@
+using System;
+
+namespace MLEM.Misc {
+ ///
+ /// This class contains a set of easing functions, adapted from .
+ /// These can be used for ui elements or any other kind of animations.
+ /// By default, each function takes an input that ranges between 0 and 1, and produces an output that roughly ranges between 0 and 1. To change this behavior, you can use and .
+ ///
+ public static class Easings {
+
+ ///
+ public static readonly Easing InSine = p => 1 - (float) Math.Cos(p * Math.PI / 2);
+ ///
+ public static readonly Easing OutSine = p => (float) Math.Sin(p * Math.PI / 2);
+ ///
+ public static readonly Easing InOutSine = p => -((float) Math.Cos(p * Math.PI) - 1) / 2;
+
+ ///
+ public static readonly Easing InQuad = p => p * p;
+ ///
+ public static readonly Easing OutQuad = p => 1 - (1 - p) * (1 - p);
+ ///
+ public static readonly Easing InOutQuad = p => p < 0.5F ? 2 * p * p : 1 - (-2 * p + 2) * (-2 * p + 2) / 2;
+
+ ///
+ public static readonly Easing InCubic = p => p * p * p;
+ ///
+ public static readonly Easing OutCubic = p => 1 - (1 - p) * (1 - p) * (1 - p);
+ ///
+ public static readonly Easing InOutCubic = p => p < 0.5F ? 4 * p * p * p : 1 - (-2 * p + 2) * (-2 * p + 2) * (-2 * p + 2) / 2;
+
+ ///
+ public static readonly Easing InExpo = p => p == 0 ? 0 : (float) Math.Pow(2, 10 * p - 10);
+ ///
+ public static readonly Easing OutExpo = p => p == 1 ? 1 : 1 - (float) Math.Pow(2, -10 * p);
+ ///
+ public static readonly Easing InOutExpo = p => p == 0 ? 0 : p == 1 ? 1 : p < 0.5F ? (float) Math.Pow(2, 20 * p - 10) / 2 : (2 - (float) Math.Pow(2, -20 * p + 10)) / 2;
+
+ ///
+ public static readonly Easing InCirc = p => 1 - (float) Math.Sqrt(1 - p * p);
+ ///
+ public static readonly Easing OutCirc = p => (float) Math.Sqrt(1 - (p - 1) * (p - 1));
+ ///
+ public static readonly Easing InOutCirc = p => p < 0.5F ? (1 - (float) Math.Sqrt(1 - 2 * p * (2 * p))) / 2 : ((float) Math.Sqrt(1 - (-2 * p + 2) * (-2 * p + 2)) + 1) / 2;
+
+ ///
+ public static readonly Easing InBack = p => 2.70158F * p * p * p - 1.70158F * p * p;
+ ///
+ public static readonly Easing OutBack = p => 1 + 2.70158F * (p - 1) * (p - 1) * (p - 1) + 1.70158F * (p - 1) * (p - 1);
+ ///
+ public static readonly Easing InOutBack = p => p < 0.5 ? 2 * p * (2 * p) * ((2.594909F + 1) * 2 * p - 2.594909F) / 2 : ((2 * p - 2) * (2 * p - 2) * ((2.594909F + 1) * (p * 2 - 2) + 2.594909F) + 2) / 2;
+
+ ///
+ public static readonly Easing InElastic = p => p == 0 ? 0 : p == 1 ? 1 : -(float) Math.Pow(2, 10 * p - 10) * (float) Math.Sin((p * 10 - 10.75) * 2.094395F);
+ ///
+ public static readonly Easing OutElastic = p => p == 0 ? 0 : p == 1 ? 1 : (float) Math.Pow(2, -10 * p) * (float) Math.Sin((p * 10 - 0.75) * 2.0943951023932F) + 1;
+ ///
+ public static readonly Easing InOutElastic = p => p == 0 ? 0 : p == 1 ? 1 : p < 0.5 ? -((float) Math.Pow(2, 20 * p - 10) * (float) Math.Sin((20 * p - 11.125) * 1.39626340159546F)) / 2 : (float) Math.Pow(2, -20 * p + 10) * (float) Math.Sin((20 * p - 11.125) * 1.39626340159546F) / 2 + 1;
+
+ ///
+ public static readonly Easing InBounce = p => 1 - OutBounce(1 - p);
+ ///
+ public static readonly Easing OutBounce = p => {
+ const float n1 = 7.5625F;
+ const float d1 = 2.75F;
+ if (p < 1 / d1) {
+ return n1 * p * p;
+ } else if (p < 2 / d1) {
+ return n1 * (p -= 1.5F / d1) * p + 0.75F;
+ } else if (p < 2.5 / d1) {
+ return n1 * (p -= 2.25F / d1) * p + 0.9375F;
+ } else {
+ return n1 * (p -= 2.625F / d1) * p + 0.984375F;
+ }
+ };
+ ///
+ public static readonly Easing InOutBounce = p => p < 0.5 ? (1 - OutBounce(1 - 2 * p)) / 2 : (1 + OutBounce(2 * p - 1)) / 2;
+
+ ///
+ /// Scales the input of an easing function, which is usually between 0 and 1, to a given minimum and maximum.
+ /// Note that the minimum needs to be smaller than the maximum.
+ ///
+ /// The easing function to scale
+ /// The minimum input value
+ /// The maximum input value
+ /// The scaled easing function
+ public static Easing ScaleInput(this Easing easing, float min, float max) {
+ return p => easing((p - min) / (max - min));
+ }
+
+ ///
+ /// Scales the output of an easing function, which is usually between 0 and 1, to a given minimum and maximum.
+ /// Note that the minimum needs to be smaller than the maximum.
+ ///
+ /// The easing function to scale
+ /// The minimum output value
+ /// The maximum output value
+ /// The scaled easing function
+ public static Easing ScaleOutput(this Easing easing, float min, float max) {
+ return p => easing(p) * (max - min) + min;
+ }
+
+ ///
+ /// A delegate method used by .
+ ///
+ /// The percentage into the easing function. Either between 0 and 1, or, if was used, between an arbitary set of values.
+ public delegate float Easing(float percentage);
+
+ }
+}
\ No newline at end of file