added naming and priorities to animations

Demos/AnimationDemo.cs

@@ -1,3 +1,4 @@
+using System;
 using Microsoft.Xna.Framework;
 using Microsoft.Xna.Framework.Graphics;
 using Microsoft.Xna.Framework.Input;
@@ -17,10 +18,10 @@ namespace Demos {
             var tex = LoadContent<Texture2D>("Textures/Anim");
 
             // create the four animations by supplying the time per frame, the texture and the four regions used
-            var downAnim = new SpriteAnimation(0.2F, tex, new Rectangle(0, 0, 8, 8), new Rectangle(0, 8, 8, 8), new Rectangle(0, 16, 8, 8), new Rectangle(0, 24, 8, 8));
+            var downAnim = new SpriteAnimation(0.2F, tex, new Rectangle(0, 0, 8, 8), new Rectangle(0, 8, 8, 8), new Rectangle(0, 16, 8, 8), new Rectangle(0, 24, 8, 8)) {Name = "Down"};
-            var upAnim = new SpriteAnimation(0.2F, tex, new Rectangle(8, 0, 8, 8), new Rectangle(8, 8, 8, 8), new Rectangle(8, 16, 8, 8), new Rectangle(8, 24, 8, 8));
+            var upAnim = new SpriteAnimation(0.2F, tex, new Rectangle(8, 0, 8, 8), new Rectangle(8, 8, 8, 8), new Rectangle(8, 16, 8, 8), new Rectangle(8, 24, 8, 8)) {Name = "Up"};
-            var leftAnim = new SpriteAnimation(0.2F, tex, new Rectangle(16, 0, 8, 8), new Rectangle(16, 8, 8, 8), new Rectangle(16, 16, 8, 8), new Rectangle(16, 24, 8, 8));
+            var leftAnim = new SpriteAnimation(0.2F, tex, new Rectangle(16, 0, 8, 8), new Rectangle(16, 8, 8, 8), new Rectangle(16, 16, 8, 8), new Rectangle(16, 24, 8, 8)) {Name = "Left"};
-            var rightAnim = new SpriteAnimation(0.2F, tex, new Rectangle(24, 0, 8, 8), new Rectangle(24, 8, 8, 8), new Rectangle(24, 16, 8, 8), new Rectangle(24, 24, 8, 8));
+            var rightAnim = new SpriteAnimation(0.2F, tex, new Rectangle(24, 0, 8, 8), new Rectangle(24, 8, 8, 8), new Rectangle(24, 16, 8, 8), new Rectangle(24, 24, 8, 8)) {Name = "Right"};
 
             // create a sprite animation group which manages a list of animations and figures out which one should
             // be playing right now based on supplied conditions
@@ -32,6 +33,16 @@ namespace Demos {
             this.group.Add(upAnim, () => this.facing == 1);
             this.group.Add(leftAnim, () => this.facing == 2);
             this.group.Add(rightAnim, () => this.facing == 3);
+
+            // you can also add a priority to an animation in the group (10 in this case, which is higher than the default of 0)
+            // if two animations' playing conditions are both true, then the one with the higher priority will be picked to play
+            // in this instance, a standing "animation" is displayed when we're facing down and also holding the space key
+            this.group.Add(new SpriteAnimation(1F, tex, new Rectangle(0, 0, 8, 8)) {Name = "DownStanding"}, () => this.facing == 0 && Input.IsKeyDown(Keys.Space), 10);
+
+            // you can also add a callback to see when the animation used changes
+            this.group.OnAnimationChanged += (anim, newAnim) => {
+                Console.WriteLine("Changing anim from " + (anim?.Name ?? "None") + " to " + (newAnim?.Name ?? "None"));
+            };
         }
 
         protected override void Update(GameTime gameTime) {

MLEM.Ui/Elements/Element.cs

@@ -213,7 +213,7 @@ namespace MLEM.Ui.Elements {
 
                 this.sortedChildren.Clear();
                 this.sortedChildren.AddRange(this.Children);
-                this.sortedChildren.Sort((e1, e2) => e1.Priority.CompareTo(e1.Priority));
+                this.sortedChildren.Sort((e1, e2) => e1.Priority.CompareTo(e2.Priority));
             }
         }
 

MLEM/Animations/SpriteAnimation.cs

@@ -10,20 +10,25 @@ namespace MLEM.Animations {
         public AnimationFrame this[int index] => this.frames[index];
         public AnimationFrame CurrentFrame {
             get {
+                // we might have overshot the end time by a little bit, so just return the last frame
+                if (this.TimeIntoAnimation >= this.TotalTime)
+                    return this.frames[this.frames.Length - 1];
                 var accum = 0D;
                 foreach (var frame in this.frames) {
                     accum += frame.Seconds;
                     if (accum >= this.TimeIntoAnimation)
                         return frame;
                 }
-                // we might have overshot the end time by a little bit, so just return the last frame
+                // if we're here then the time is negative for some reason, so just return the first frame
-                return this.frames[this.frames.Length - 1];
+                Console.WriteLine("Test");
+                return this.frames[0];
             }
         }
         public TextureRegion CurrentRegion => this.CurrentFrame.Region;
         public readonly double TotalTime;
         public double TimeIntoAnimation { get; private set; }
         public bool IsFinished { get; private set; }
+        public string Name;
 
         public bool IsLooping = true;
         public Completed OnCompleted;

MLEM/Animations/SpriteAnimationGroup.cs

@@ -11,37 +11,55 @@ namespace MLEM.Animations {
         public SpriteAnimation CurrentAnimation => this.currAnimation?.Animation;
         public AnimationFrame CurrentFrame => this.CurrentAnimation?.CurrentFrame;
         public TextureRegion CurrentRegion => this.CurrentAnimation?.CurrentRegion;
+        public AnimationChanged OnAnimationChanged;
 
-        public SpriteAnimationGroup Add(SpriteAnimation anim, Func<bool> condition) {
+        public SpriteAnimationGroup Add(SpriteAnimation anim, Func<bool> condition, int priority = 0) {
-            this.animations.Add(new ConditionedAnimation(anim, condition));
+            this.animations.Add(new ConditionedAnimation(anim, condition, priority));
+            this.animations.Sort((a1, a2) => a1.Priority.CompareTo(a2.Priority));
             return this;
         }
 
         public void Update(GameTime time) {
-            if (this.currAnimation == null || !this.currAnimation.ShouldPlay()) {
+            ConditionedAnimation animToPlay = null;
-                this.currAnimation = null;
+            if (this.currAnimation != null && this.currAnimation.ShouldPlay())
+                animToPlay = this.currAnimation;
             foreach (var anim in this.animations) {
-                    if (anim.ShouldPlay()) {
+                // if we find an animation with a lower priority then it means we can break
-                        this.currAnimation = anim;
+                // because the list is sorted by priority
-                        anim.Animation.Restart();
+                if (animToPlay != null && anim.Priority < animToPlay.Priority)
                     break;
+                if (anim.ShouldPlay())
+                    animToPlay = anim;
             }
+            if (animToPlay != this.currAnimation) {
+                this.OnAnimationChanged?.Invoke(this.currAnimation?.Animation, animToPlay?.Animation);
+                this.currAnimation = animToPlay;
+                if (animToPlay != null)
+                    animToPlay.Animation.Restart();
             }
-            }
+
             if (this.currAnimation != null)
                 this.currAnimation.Animation.Update(time);
         }
 
+        public SpriteAnimation ByName(string name) {
+            return this.animations.Find(anim => anim.Animation.Name == name)?.Animation;
+        }
+
+        public delegate void AnimationChanged(SpriteAnimation oldAnim, SpriteAnimation newAnim);
+
     }
 
     internal class ConditionedAnimation {
 
         public readonly SpriteAnimation Animation;
         public readonly Func<bool> ShouldPlay;
+        public readonly int Priority;
 
-        public ConditionedAnimation(SpriteAnimation animation, Func<bool> shouldPlay) {
+        public ConditionedAnimation(SpriteAnimation animation, Func<bool> shouldPlay, int priority) {
             this.Animation = animation;
             this.ShouldPlay = shouldPlay;
+            this.Priority = priority;
         }
 
     }