Add an expression to get the number of frames in the current animation of a sprite object (#4722)

Author: D8H

Core/GDCore/Extensions/Builtin/SpriteExtension/SpriteExtension.cpp

@@ -583,7 +583,14 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
 
   obj.AddExpression("Sprite",
                     _("Image"),
-                    _("Animation frame of the object"),
+                    _("Current frame of the animation of the object"),
+                    _("Animations and images"),
+                    "res/actions/sprite.png")
+      .AddParameter("object", _("Object"), "Sprite");
+
+  obj.AddExpression("AnimationFrameCount",
+                    _("Number of frames"),
+                    _("Number of frames in the current animation of the object"),
                     _("Animations and images"),
                     "res/actions/sprite.png")
       .AddParameter("object", _("Object"), "Sprite");

GDJS/GDJS/Extensions/Builtin/SpriteExtension.cpp

@@ -108,6 +108,7 @@ SpriteExtension::SpriteExtension() {
   spriteExpressions["Animation"].SetFunctionName("getAnimation");
   spriteStrExpressions["AnimationName"].SetFunctionName("getAnimationName");
   spriteExpressions["Sprite"].SetFunctionName("getAnimationFrame");
+  spriteExpressions["AnimationFrameCount"].SetFunctionName("getAnimationFrameCount");
   spriteExpressions["AnimationSpeedScale"].SetFunctionName(
       "getAnimationSpeedScale");
   spriteExpressions["ScaleX"].SetFunctionName("getScaleX");

GDJS/Runtime/spriteruntimeobject.ts

@@ -754,6 +754,17 @@ namespace gdjs {
       return this._currentFrame;
     }
 
+    getAnimationFrameCount(): number {
+      if (this._currentAnimation >= this._animations.length) {
+        return 0;
+      }
+      const currentAnimation = this._animations[this._currentAnimation];
+      if (this._currentDirection >= currentAnimation.directions.length) {
+        return 0;
+      }
+      return currentAnimation.directions[this._currentDirection].frames.length;
+    }
+
     /**
      * @deprecated
      * Return true if animation has ended.