SpriteAnimation: introduce imageRange

engine/modules/entities/src/main/java/com/codingame/gameengine/module/entities/Serializer.java

@@ -60,6 +60,7 @@ class Serializer {
         keys.put("zIndex", "z");
         keys.put("blendMode", "b");
         keys.put("images", "I");
+        keys.put("imageRange", "IR");
         keys.put("restarted", "rs");
         keys.put("playing", "p");
         keys.put("loop", "l");

engine/modules/entities/src/main/java/com/codingame/gameengine/module/entities/SpriteAnimation.java

@@ -1,5 +1,6 @@
 package com.codingame.gameengine.module.entities;
 
+import java.util.Arrays;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
@@ -169,7 +170,15 @@ public SpriteAnimation setImages(String... images) {
             throw new IllegalArgumentException("Animation must contain at least 1 image.");
         }
         this.images = images;
-        set("images", Stream.of(images).collect(Collectors.joining(",")), null);
+        String[] compressed = compressImages();
+        if (compressed == images) {
+            set("images", Stream.of(images).collect(Collectors.joining(",")), null);
+            set("imageRange", "");
+        }
+        else {
+            set("images", "");
+            set("imageRange", compressed[0], null);
+        }
         return this;
     }
 
@@ -181,4 +190,29 @@ public SpriteAnimation setImages(String... images) {
     public String[] getImages() {
         return images;
     }
-}
+
+    private String[] compressImages() {
+        if (Stream.of(images).anyMatch(i -> i.contains("|"))) return images;
+        String uncompressed = Stream.of(images).collect(Collectors.joining(","));
+        for (int prefixLength = images[0].length() - 1; prefixLength > 0; prefixLength--) {
+            String prefix = images[0].substring(0, prefixLength);
+            String numberText = images[0].substring(prefixLength);
+            int start = 0;
+            try {
+                start = Integer.parseInt(numberText);
+            } catch (NumberFormatException ex) {
+                break; // can't parse, no compression possible
+            }
+            boolean validPrefix = true;
+            for (int i = 1; i < images.length; i++) {
+                String suffix = String.format("%0" + numberText.length() + "d", start + i); // add leading zeros
+                if (!images[i].equals(prefix + suffix)) validPrefix = false;
+            }
+            if (!validPrefix) continue;
+            String compressed = prefix + "|" + numberText + "|" + images[images.length - 1].substring(prefixLength);
+            if (compressed.length() < uncompressed.length())
+                return new String[]{compressed};
+        }
+        return images;
+    }
+}

engine/modules/entities/src/main/resources/view/entity-module/Command.js

@@ -38,6 +38,7 @@ const PROPERTY_KEY_MAP = {
   z: 'zIndex',
   b: 'blendMode',
   I: 'images',
+  IR: 'imageRange',
   rs: 'restarted',
   p: 'playing',
   l: 'loop',

engine/modules/entities/src/main/resources/view/entity-module/SpriteAnimation.js

@@ -10,6 +10,7 @@ export class SpriteAnimation extends TextureBasedEntity {
     super()
     Object.assign(this.defaultState, {
       images: '',
+      imageRange: '',
       loop: false,
       duration: 1000,
       playing: true,
@@ -34,6 +35,20 @@ export class SpriteAnimation extends TextureBasedEntity {
   updateDisplay (state, changed, globalData, frame, progress) {
     super.updateDisplay(state, changed, globalData)
 
+    if (state.imageRange) {
+      let parts = state.imageRange.split('|')
+      let prefix = parts[0]
+      let startText = parts[1]
+      let lastImage = prefix + parts[2]
+      let images = [prefix + startText]
+      for (let i = 1; images[images.length - 1] !== lastImage; i++) {
+        let suffix = `${+startText + i}`
+        while (suffix.length < startText.length) suffix = '0' + suffix
+        images.push(prefix + suffix)
+      }
+      state.images = images.join(',')
+    }
+
     if (state.images) {
       const images = state.images.split(',')
 

engine/modules/entities/src/main/resources/view/entity-module/properties.js

@@ -77,6 +77,7 @@ export const PROPERTIES = {
   baseHeight: constOpts,
   image: stringOpts,
   images: stringOpts,
+  imageRange: stringOpts,
   scaleMode: stringOpts,
   restarted: {
     type: String,