Constraining scaling [SOLVED]

[dave]

Hi there,

Ok basically when I add items to my TransformManager, I place them there at 70% but I want to stop the user from scaling them past 100% (and probably stop them scaling them lower than 20% or so too). So far, I haven't seen a property which lets me specify a restriction like this so I thought about using the TransformEvent.SCALE event. However, it just seems to execute once, when the mouse is released. My plan was to check for the scale being greater than 1 and if it is, setting it to 1 but if this event is only fired on release, that's not going to happen.

 

So yeah, basically I'm wondering what approach you would take to this. Is there a parameter lurking somewhere that would just sort this for me? If not, it would be a nice addition to TM as I think a lot of people would like to stop their images from being scaled higher than 100%, degrading the image quality. Maybe a MaxScale/MinScale type option...

[GreenSock]

Wish granted.

 

I just added the ability to set minScaleX, maxScaleX, minScaleY, and maxScaleY properties to TransformItem instances in version 1.2. You should have received an e-mail about the update with instructions about how to get it this morning.

 

Enjoy!

[dave]

Hi, this sounds great but for some reason, I'm not seeing how I can add this functionality into my app. I'm pretty sure I'm just having a bit of "first day back to work" stupidity but...

The way I'm using TM at the moment is to create a new movieclip object, then simply "transformManager.addItem(myMC);" which works but, as far as I can see, these new properties are available only when creating a new "TransformItem" instance, which I can do fine. However, how do I then actually add a TransformItem to my TransformManager? The transformManager.addItem() only accepts DisplayObjects!

Again, forgive my stupidity. I'm sure it's very simple but I don't think my coffee's kicked in yet...

[GreenSock]

Sip the coffee....let the caffeine kick in....

 

Feeling better?

 

Okay, good question. addItem() returns a TransformItem, so you can just use that to add the min/max scale, like so:

 

var myItem:TransformItem = myManager.addItem(myDisplayObject);
myItem.setScaleConstraints(0.5, 1, 0.5, 1);

//or set them directly if you don't want to use the setScaleConstraints();
myItem.minScaleX = 0.5;
myItem.maxScaleX = 1;
myItem.minScaleY = 0.5;
myItem.maxScaleY = 1;

 

You can also get the TransformItem associated with your DisplayObject anytime using the getItem() method, like:

 

var myItem:TransformItem = myManager.getItem(myDisplayObject);

 

(that assumes you've already used the addItem() at some point to add the DisplayObject to the TransformManager instance)

 

Does that clear things up?

[dave]

Aha! The secret was that I don't actually "create" a TransformItem myself. addItem was actually returning one for me! Clever...

Anyways yes, that works awesome now and I think it's a great addition to the featureset. Greatly appreciated...

[dave]

Ah, this new feature is great but there's a bug I've just noticed...

First off, I've got my minimum scales set to 0.2, my max to 1 and images are set to 0.7 scale before being added to the TransformManager. Anyways, if I add an item, rotate it 180 degrees clockwise, then resize using the handles on the left of the screen (on the right if it's at 0 degrees rotation), it snaps to the minimum scale in the 0 degrees rotation position. Any ideas?

[GreenSock]

there's a bug I've just noticed...

 

Great catch! Sorry about that. I just fixed it and released an update. You should have already received an e-mail about it by now.

 

Jack