what the fuck

Author: charlesisfeline

source/flixel/tweens/misc/VarTween.hx

@@ -0,0 +1,138 @@
+package flixel.tweens.misc;
+
+import flixel.tweens.FlxTween;
+
+/**
+ * Tweens multiple numeric properties of an object simultaneously.
+ */
+class VarTween extends FlxTween
+{
+    var _object:Dynamic;
+    var _properties:Dynamic;
+    var _propertyInfos:Array<VarTweenProperty>;
+    
+    function new(options:TweenOptions, ?manager:FlxTweenManager)
+    {
+        super(options, manager);
+    }
+    
+    /**
+     * Tweens multiple numeric public properties.
+     *
+     * @param	object		The object containing the properties.
+     * @param	properties	An object containing key/value pairs of properties and target values.
+     * @param	duration	Duration of the tween.
+     */
+    public function tween(object:Dynamic, properties:Dynamic, duration:Float):VarTween
+    {
+        #if FLX_DEBUG
+        if (object == null) throw "Cannot tween variables of an object that is null.";
+        else if (properties == null) throw "Cannot tween null properties.";
+        #end
+        
+        _object = object;
+        _properties = properties;
+        _propertyInfos = [];
+        this.duration = duration;
+        start();
+        initializeVars();
+        return this;
+    }
+    
+    override function update(elapsed:Float):Void
+    {
+        var delay:Float = (executions > 0) ? loopDelay : startDelay;
+        
+        // Leave properties alone until delay is over
+        if (_secondsSinceStart < delay) super.update(elapsed);
+        else
+        {
+            // Wait until the delay is done to set the starting values of tweens
+            if (Math.isNaN(_propertyInfos[0].startValue)) setStartValues();
+            
+            super.update(elapsed);
+            
+            if (active) for (info in _propertyInfos)
+                Reflect.setProperty(info.object, info.field, info.startValue + info.range * scale);
+        }
+    }
+    
+    function initializeVars():Void
+    {
+        var fieldPaths:Array<String>;
+        if (Reflect.isObject(_properties)) fieldPaths = Reflect.fields(_properties);
+        else
+            throw "Unsupported properties container - use an object containing key/value pairs.";
+            
+        for (fieldPath in fieldPaths)
+        {
+            var target = _object;
+            var path = fieldPath.split(".");
+            var field = path.pop();
+            for (component in path)
+            {
+                target = Reflect.getProperty(target, component);
+                if (!Reflect.isObject(target)) throw 'The object does not have the property "$component" in "$fieldPath"';
+            }
+            
+            _propertyInfos.push({
+                object: target,
+                field: field,
+                startValue: Math.NaN, // gets set after delay
+                range: Reflect.getProperty(_properties, fieldPath)
+            });
+        }
+    }
+    
+    function setStartValues()
+    {
+        for (info in _propertyInfos)
+        {
+            // if (Reflect.getProperty(info.object, info.field) == null) throw 'The object does not have the property "${info.field}"';
+            if (Reflect.getProperty(info.object, info.field) == null)
+            {
+                trace('The object does not have the property "${info.field}"');
+                return;
+            }
+            
+            var value:Dynamic = Reflect.getProperty(info.object, info.field);
+            // if (Math.isNaN(value)) throw 'The property "${info.field}" is not numeric.';
+            if (Math.isNaN(value))
+            {
+                trace('The property "${info.field}" is not numeric');
+                return;
+            }
+            
+            info.startValue = value;
+            info.range = info.range - value;
+        }
+    }
+    
+    override public function destroy():Void
+    {
+        super.destroy();
+        _object = null;
+        _properties = null;
+        _propertyInfos = null;
+    }
+    
+    override function isTweenOf(object:Dynamic, ?field:String):Bool
+    {
+        if (object == _object && field == null) return true;
+        
+        for (property in _propertyInfos)
+        {
+            if (object == property.object && (field == property.field || field == null)) return true;
+        }
+        
+        return false;
+    }
+}
+
+private typedef VarTweenProperty =
+{
+    object:Dynamic,
+    field:String,
+    startValue:Float,
+    range:Float
+}