Animated item support

core/src/mindustry/type/Item.java

@@ -1,8 +1,14 @@
 package mindustry.type;
 
+import arc.*;
 import arc.graphics.*;
+import arc.graphics.g2d.*;
 import arc.struct.*;
+import arc.util.*;
 import mindustry.ctype.*;
+import mindustry.game.EventType.*;
+import mindustry.graphics.*;
+import mindustry.graphics.MultiPacker.*;
 import mindustry.world.blocks.environment.*;
 import mindustry.world.meta.*;
 
@@ -29,6 +35,13 @@ public class Item extends UnlockableContent{
     /** if true, this item is of lowest priority to drills. */
     public boolean lowPriority;
 
+    /** If >0, this item is animated. */
+    public int frames = 0;
+    /** Number of generated transition frames between each frame */
+    public int transitionFrames = 0;
+    /** Ticks in-between animation frames. */
+    public float frameTime = 5f;
+
     public Item(String name, Color color){
         super(name);
         this.color = color;
@@ -38,6 +51,40 @@ public class Item extends UnlockableContent{
         this(name, new Color(Color.black));
     }
 
+    @Override
+    public void loadIcon(){
+        super.loadIcon();
+
+        //animation code ""borrowed"" from Project Unity - original implementation by GlennFolker and sk7725
+        if(frames > 0){
+            TextureRegion[] regions = new TextureRegion[frames * (transitionFrames + 1)];
+
+            if(transitionFrames <= 0){
+                for(int i = 1; i <= frames; i++){
+                    regions[i - 1] = Core.atlas.find(name + i);
+                }
+            }else{
+                for(int i = 0; i < frames; i++){
+                    regions[i * (transitionFrames + 1)] = Core.atlas.find(name + (i + 1));
+                    for(int j = 1; j <= transitionFrames; j++){
+                        int index = i * (transitionFrames + 1) + j;
+                        regions[index] = Core.atlas.find(name + "-t" + index);
+                    }
+                }
+            }
+
+            fullIcon = new TextureRegion(fullIcon);
+            uiIcon = new TextureRegion(uiIcon);
+
+            Events.run(Trigger.update, () -> {
+                int frame = (int)(Time.globalTime / frameTime) % regions.length;
+
+                fullIcon.set(regions[frame]);
+                uiIcon.set(regions[frame]);
+            });
+        }
+    }
+
     @Override
     public void setStats(){
         stats.addPercent(Stat.explosiveness, explosiveness);
@@ -56,6 +103,30 @@ public class Item extends UnlockableContent{
         return ContentType.item;
     }
 
+    @Override
+    public void createIcons(MultiPacker packer){
+        super.createIcons(packer);
+
+        //create transitions
+        if(frames > 0 && transitionFrames > 0){
+            var pixmaps = new PixmapRegion[frames];
+
+            for(int i = 0; i < frames; i++){
+                pixmaps[i] = Core.atlas.getPixmap(name + (i + 1));
+            }
+
+            for(int i = 0; i < frames; i++){
+                for(int j = 1; j <= transitionFrames; j++){
+                    float f = (float)j / (transitionFrames + 1);
+                    int index = i * (transitionFrames + 1) + j;
+
+                    Pixmap res = Pixmaps.blend(pixmaps[i], pixmaps[(i + 1) % frames], f);
+                    packer.add(PageType.main, name + "-t" + index, res);
+                }
+            }
+        }
+    }
+
     /** Allocates a new array containing all items that generate ores. */
     public static Seq<Item> getAllOres(){
         return content.blocks().select(b -> b instanceof OreBlock).map(b -> b.itemDrop);