Graphics: Add texture fade function

Furball.Engine/Engine/Graphics/Drawables/TexturedDrawable.cs

@@ -1,10 +1,14 @@
-
+using System;
 using System.Drawing;
 using System.Numerics;
 using Furball.Engine.Engine.Graphics.Drawables.Managers;
+using Furball.Engine.Engine.Graphics.Drawables.Tweens;
+using Furball.Engine.Engine.Graphics.Drawables.Tweens.TweenTypes;
 using Furball.Vixie;
+using JetBrains.Annotations;
+using Color=Furball.Vixie.Backends.Shared.Color;
 
-namespace Furball.Engine.Engine.Graphics.Drawables; 
+namespace Furball.Engine.Engine.Graphics.Drawables;
 
 /// <summary>
 /// A Basic Managed Drawable that just Draws a Texture to the Screen,
@@ -23,7 +27,19 @@ public class TexturedDrawable : Drawable {
     /// Unprocessed Size of the Drawable in Pixels
     /// <remarks>This variable does not get changed as the DrawableManager translates the Drawable to be Scaled to be properly visible on all resolutions</remarks>
     /// </summary>
-    public override Vector2 Size => this.Cropping == null ? new Vector2(this.Texture.Size.X, this.Texture.Size.Y) * this.Scale : new Vector2(this.Cropping.Value.Width, this.Cropping.Value.Height) * this.Scale;
+    public override Vector2 Size => this.Cropping == null
+                                        ? new Vector2(this.Texture.Size.X,       this.Texture.Size.Y) * this.Scale
+                                        : new Vector2(this.Cropping.Value.Width, this.Cropping.Value.Height) * this.Scale;
+
+    private FloatTween _fadeTextureTween = null;
+    private Texture    _fadeTextureTo;
+    public void FadeTexture(Texture tex, double time, Easing easing = Easing.None) {
+        if (tex.Size != this.Texture.Size)
+            throw new Exception("Sizes of the fading textures must match!");
+
+        this._fadeTextureTween = new FloatTween(TweenType.Fade, 0, 1, FurballGame.Time, FurballGame.Time + time, easing);
+        this._fadeTextureTo    = tex;
+    }
 
     /// <summary>
     /// TexturedDrawable Constructor
@@ -35,6 +51,7 @@ public TexturedDrawable(Texture texture, Vector2 position) {
 
         this.Texture = texture;
     }
+
     /// <summary>
     /// TexturedDrawable Constructor that allows for Cropping
     /// </summary>
@@ -50,19 +67,47 @@ public TexturedDrawable(Texture texture, Vector2 position, Rectangle cropping, f
         this.Texture  = texture;
     }
 
+    public override void Update(double time) {
+        base.Update(time);
+
+        //Update the tween with the current time of the drawable
+        this._fadeTextureTween?.Update(this.DrawableTime);
+
+        //If the tween is terminated, then we are fully faded to the new texture
+        if (this._fadeTextureTween is {
+                Terminated: true
+            }) {
+            this.Texture           = this._fadeTextureTo;
+            this._fadeTextureTween = null;
+            this._fadeTextureTo    = null;
+        }
+    }
+
     public override void Draw(double time, DrawableBatch batch, DrawableManagerArgs args) {
-        if(this.Cropping != null)
-            batch.Draw(
-            this.Texture,
-            args.Position,
-            args.Scale,
-            args.Rotation,
-            args.Color,
-            this.Cropping.Value,
-            args.Effects,
-            this.RotationOrigin 
-            );
-        else
-            batch.Draw(this.Texture, args.Position, args.Scale, args.Rotation, args.Color, args.Effects, this.RotationOrigin);
+        if (this.Cropping != null) {
+            if (this._fadeTextureTween != null) {
+                float progress = this._fadeTextureTween.GetCurrent();
+
+                Color orig = args.Color with {
+                    Af = args.Color.Af * (1f - progress)
+                };
+
+                batch.Draw(this._fadeTextureTo, args.Position, args.Scale, args.Rotation, args.Color, this.Cropping.Value, args.Effects, this.RotationOrigin);
+                batch.Draw(this.Texture,        args.Position, args.Scale, args.Rotation, orig,       this.Cropping.Value, args.Effects, this.RotationOrigin);
+            } else
+                batch.Draw(this.Texture, args.Position, args.Scale, args.Rotation, args.Color, this.Cropping.Value, args.Effects, this.RotationOrigin);
+        } else {
+            if (this._fadeTextureTween != null) {
+                float progress = this._fadeTextureTween.GetCurrent();
+
+                Color orig = args.Color with {
+                    Af = args.Color.Af * (1f - progress)
+                };
+
+                batch.Draw(this._fadeTextureTo, args.Position, args.Scale, args.Rotation, args.Color, args.Effects, this.RotationOrigin);
+                batch.Draw(this.Texture,        args.Position, args.Scale, args.Rotation, orig,       args.Effects, this.RotationOrigin);
+            } else
+                batch.Draw(this.Texture, args.Position, args.Scale, args.Rotation, args.Color, args.Effects, this.RotationOrigin);
+        }
     }
-}
+}

Furball.Game/FurballTestGame.cs

@@ -71,6 +71,7 @@ protected override void InitializeLocalizations() {
         LocalizationManager.AddDefaultTranslation(LocalizationStrings.GMLTest,              "GML Test");
         LocalizationManager.AddDefaultTranslation(LocalizationStrings.TexturePackerTest,    "Texture Packer Test");
         LocalizationManager.AddDefaultTranslation(LocalizationStrings.BoxBlurTest,          "Box Blur Test");
+        LocalizationManager.AddDefaultTranslation(LocalizationStrings.TextureFadeTest,      "Texture Fade Test");
 
         LocalizationManager.AddDefaultTranslation(LocalizationStrings.ChooseScreen, "Choose Screen");
     }

Furball.Game/LocalizationStrings.cs

@@ -29,4 +29,5 @@ public enum LocalizationStrings {
     GMLTest,
     TexturePackerTest,
     BoxBlurTest,
+    TextureFadeTest
 }

Furball.Game/Screens/ScreenSelector.cs

@@ -48,7 +48,8 @@ public override void Initialize() {
             (LocalizationStrings.GraphTest, typeof(GraphTest)),
             (LocalizationStrings.GMLTest, typeof(GMLTest)),
             (LocalizationStrings.TexturePackerTest, typeof(TexturePackerTest)),
-            (LocalizationStrings.BoxBlurTest, typeof(BoxBlurTest))
+            (LocalizationStrings.BoxBlurTest, typeof(BoxBlurTest)),
+            (LocalizationStrings.TextureFadeTest, typeof(TextureFadeTest))
         };
 
         this.Manager.Add(this._topText = new TextDrawable(new Vector2(1280f / 2f, 40), FurballGame.DefaultFont, LocalizationManager.GetLocalizedString(LocalizationStrings.ChooseScreen), 48) {

Furball.Game/Screens/Tests/TextureFadeTest.cs

@@ -0,0 +1,40 @@
+using System.Numerics;
+using Furball.Engine;
+using Furball.Engine.Engine.Graphics;
+using Furball.Engine.Engine.Graphics.Drawables;
+using Furball.Engine.Engine.Graphics.Drawables.UiElements;
+using Furball.Engine.Engine.Input.Events;
+using Furball.Vixie;
+using Furball.Vixie.Backends.Shared;
+using Furball.Vixie.Backends.Shared.TextureEffects.Blur;
+
+namespace Furball.Game.Screens.Tests;
+
+public class TextureFadeTest : TestScreen {
+    private TexturedDrawable     _textureDrawable;
+    private Texture              _source;
+    private BoxBlurTextureEffect _blur;
+    private Texture         _dest;
+
+    public override void Initialize() {
+        base.Initialize();
+
+        this._source = ContentManager.LoadTextureFromFileCached("inviswater.png");
+        this._blur = FurballGame.Instance.WindowManager.GraphicsBackend.CreateBoxBlurTextureEffect(this._source);
+        this._dest   = new Texture(this._blur.Texture);
+        this._blur.UpdateTexture();
+
+        this.Manager.Add(this._textureDrawable = new TexturedDrawable(this._source, new Vector2(10)));
+
+        this.Manager.Add(
+        new DrawableButton(new Vector2(10), FurballGame.DefaultFont, 24, "Fade texture", Color.Blue, Color.White, Color.Black, Vector2.Zero, FadeTexture) {
+            ScreenOriginType = OriginType.TopRight, 
+            OriginType = OriginType.TopRight
+        }
+        );
+    }
+
+    private void FadeTexture(object sender, MouseButtonEventArgs e) {
+        this._textureDrawable.FadeTexture(this._textureDrawable.Texture == this._source ? this._dest : this._source, 1000);
+    }
+}