Room Panning

Room Panning
Has anyone done a tutorial/discussed how screen panning works? a) I've got a 1200x600p background image and want the the room to pan with the character as he moves past say 600 horizontal pixels. b) The second effect I'm trying to create is a screen pan where the character ISN'T moving. ie. character looks at the sunset, screen pans to centre on view of the sunset in the background image (reminiscent of games like Dig). I've created a blank cast member and used MoveToPoint(), but need the screen to pan with the character. Other options? Comments? Cheers, idzol

You first scenario (following the character) is an automatic feature of the engine. When you have a bgimage larger than the screen, the engine will automatically pan to follow the character as it gets close to the edge. See documentation on the following fields in the room editor: "sEdge" (scroll edge), "sRange" (scroll range) and "%" (percentace of scroll speed relative to the rate of the character's movement). As for the second... how's your action script? That would be easy enough to write a dirt-simple action to handle. But no, it's not a built-in feature of the engine.

Write what in actionscript
Are you proposing an animation of the background panning to sunset in a new frame, and then play that frame when the char looks at sunset? My concern with this approach is that if the character is currently in view - on the cliff say - the background would move in the animation but the character would remain stationary. You think Actionscript moving the whole stage (as a new custom TIMe)? Cheers, idzol PS. also just found the thread on scrolling forumer.com/viewtopic.php?t=105" target="_blank">http://lassie.10.forumer.com/viewtopic.php?t=105

Re: Write what in actionscript
You think Actionscript moving the whole stage (as a new custom TIMe)? Exactly. Extremely simple... you'll find that there is a DOM diagram of the Lassie architecture contained within the TIMe dictionary. As I recall, the room-level object is called "room" and is located on root. So, you'd just create a handy little TIMe that goes something like this:



function myCoolTIMe(): Void {
	_root.room.onEnterFrame = function() {
		//ASSIGN THESE VALUES
		var xtarget:Number = 100; //total pixel offset that the room should shift to
		var inc:Number = 5; //pixel increment (speed) of pan animation
		
		//DON'T TOUCH THE REST
		var dir:Number = (xtarget>this._x) ? 1 : -1;
		var dif:Number = Math.abs(this._x-xtarget);
		if (dif<=inc) {
			this._x = xtarget;
			delete this.onEnterFrame;
		} else {
			this._x+=(inc*dir);
		}
	}
}

Mind you, I just typed that as text off the top of my head so I can't guarantee that my syntax isn't flawed. However, that's the idea... pretty simple stuff if you have an intermediate understanding of AS.

Thanks Mac!
Thanks, I'll be sure to send through the code if/when I get it working. I like the idea of a flash developer community collaborating on this project. I would really like to see LassieAS become the defacto standard for flash adventure games! Cheers, idzol

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