QPropertyAnimations in Qt Script

[Scorp2us]

So I can't get this to work. The xScale factor should be animated. It works in C++ but not QtScript. You will need qt-master and the latest bindings generator (4.6 branch)
The only message I get is "QPropertyAnimation::updateState: Changing state of an animation without target"

http://pastebin.com/m51cee344
or

function GraphicsItemPropertyProxy (item, parent)
{
	//QObject.call(parent);
	this.item = item;
	this._xScale = 1;
}
 
GraphicsItemPropertyProxy.prototype = new QObject();
GraphicsItemPropertyProxy.__defineGetter__("xScale", function() { return this._xScale; });
GraphicsItemPropertyProxy.__defineSetter__("xScale", 
	function(v) { 
		print("setting xScale to", v); 
		this._xScale = v; 
		this.updateTransform(); 
		return v; 
	}
);
GraphicsItemPropertyProxy.prototype.updateTransform=function() {
	print("updateTransform()");
	this.item.setTransform(new QTransform().translate(0,0)
		.rotate(0, Qt.ZAxis)
		.rotate(0, Qt.YAxis)
		.rotate(0, Qt.XAxis)
		.scale(this._xScale, 5)
		.translate(0, 0));
}
 
function AffineTextItem(text, font, brush, parent)
{
	QGraphicsItem.call(this, parent);
	var fm = new QFontMetrics(font);
 
	this.path = new QPainterPath();
	this.brush=brush;
	this.path.addText(0,fm.ascent(), this.font, text);
	this.br = fm.boundingRect(text).adjusted(0,0,0, fm.ascent());
	this.boundingRect = function() { return this.br; };
}
 
AffineTextItem.prototype = new QGraphicsItem();
 
AffineTextItem.prototype.paint = function (painter, options, widget)
{
	if (this.opacity()==0)
		return;
	painter.fillPath(this.path, this.brush);
}
 
 
var scene =  new QGraphicsScene();
scene.setSceneRect(0,0, 900, 500);
 
 
var item = new AffineTextItem("this is text", new QFont("Arial", 25), new QColor(255,0,0));
item.setOpacity(0.75);
scene.addItem(item);
var proxy = new GraphicsItemPropertyProxy(item);
var animX = new QPropertyAnimation(proxy, "xScale");
animX.startValue = 50.0;
animX.endValue = 10.0;
animX.duration = 5000.0;
animX.loopCount = -1;
 
var view = new QGraphicsView(scene);
view.renderHints = (QPainter.Antialiasing | QPainter.SmoothPixmapTransform | QPainter.TextAntialiasing);
 
var blueGradient = new QLinearGradient (0,0,0,1080);
blueGradient.setColorAt(0, new QColor(0,255,0));
blueGradient.setColorAt(1, new QColor(0,0,255));
 
view.backgroundBrush = new QBrush(blueGradient);
animX.start();
view.resize(960, 540);
view.show();
QCoreApplication.exec();

function GraphicsItemPropertyProxy (item, parent)
{
	//QObject.call(parent);
	this.item = item;
	this._xScale = 1;
}

GraphicsItemPropertyProxy.prototype = new QObject();
GraphicsItemPropertyProxy.__defineGetter__("xScale", function() { return this._xScale; });
GraphicsItemPropertyProxy.__defineSetter__("xScale", 
	function(v) { 
		print("setting xScale to", v); 
		this._xScale = v; 
		this.updateTransform(); 
		return v; 
	}
);
GraphicsItemPropertyProxy.prototype.updateTransform=function() {
	print("updateTransform()");
	this.item.setTransform(new QTransform().translate(0,0)
		.rotate(0, Qt.ZAxis)
		.rotate(0, Qt.YAxis)
		.rotate(0, Qt.XAxis)
		.scale(this._xScale, 5)
		.translate(0, 0));
}

function AffineTextItem(text, font, brush, parent)
{
	QGraphicsItem.call(this, parent);
	var fm = new QFontMetrics(font);

	this.path = new QPainterPath();
	this.brush=brush;
	this.path.addText(0,fm.ascent(), this.font, text);
	this.br = fm.boundingRect(text).adjusted(0,0,0, fm.ascent());
	this.boundingRect = function() { return this.br; };
}

AffineTextItem.prototype = new QGraphicsItem();

AffineTextItem.prototype.paint = function (painter, options, widget)
{
	if (this.opacity()==0)
		return;
	painter.fillPath(this.path, this.brush);
}


var scene =  new QGraphicsScene();
scene.setSceneRect(0,0, 900, 500);


var item = new AffineTextItem("this is text", new QFont("Arial", 25), new QColor(255,0,0));
item.setOpacity(0.75);
scene.addItem(item);
var proxy = new GraphicsItemPropertyProxy(item);
var animX = new QPropertyAnimation(proxy, "xScale");
animX.startValue = 50.0;
animX.endValue = 10.0;
animX.duration = 5000.0;
animX.loopCount = -1;

var view = new QGraphicsView(scene);
view.renderHints = (QPainter.Antialiasing | QPainter.SmoothPixmapTransform | QPainter.TextAntialiasing);

var blueGradient = new QLinearGradient (0,0,0,1080);
blueGradient.setColorAt(0, new QColor(0,255,0));
blueGradient.setColorAt(1, new QColor(0,0,255));

view.backgroundBrush = new QBrush(blueGradient);
animX.start();
view.resize(960, 540);
view.show();
QCoreApplication.exec();

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[Scorp2us]

I am now offering $20 via PayPal for a working QtScript solution.

To qualify, you must use the GraphicsItemPropertyProxy technique from the script (lines 1-26) and the general approach of lines 57-75.

From what I can tell the QPropertyAnimation is not accepting the item passed in because d->target is null. It is my understanding that javascript objects are interchangeable with QObjects, so this should work.