Moments of Flash, ActionScript, Flex

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How does one rasterize a transformed vector capturing it's new dimensions without pixelation?


Note: This follows my previous post Matrix Not Synchronized


Challenge: To render a bitmap of a transformed vector display object without pixelation. Specifically, after a mx.controls.Text is transformed, a bitmap snapshot is needed to be taken of the new object including the dimensions.  I should note that the reason I am needing to get a bitmap snapshot is do to some shaping to the text.


Problem: However, doing so results in pixelation or resamples / renders the original dimensions of the transformed Text. It appears that flash.display.BitmapData::draw cannot get the new transformed display. In other words,  when a flash.display.InteractiveObject is scaled on the x axis (or any axis) using transform.matrix, flash.display.BitmapData::draw cannot capture the new dimensions of the display object.


Example: http://sources.novelastudios.com/flash/matrix_adustments/MatriciesAndDimensions.html#
When the application creation complete is fired a snapshot is made. Change the matrix width (transform.matrix.a) and then re-render a snapshot / bitmap. Notice it retains the original, non-transformed values. Therefore and considering it is a rastered snapshot, when the snapshot/bitmap is scaled it becomes pixelated. Example version was 1.1.0.0 that should this problem. Version 1.2.0.0 is a workaround for now showing the workaround.


Workaround: I give credit to Guy Stables (needs a link) and Alex Harui (http://blogs.adobe.com/aharui).  Essentially, the workaround is as follows:

1. The InteractiveObject (we'll call our target) needs to be placed in a container. In this example mx.controls.Text is placed inside a mx.core.UIComponent. 
2. The matrix transform is then applied to the target (eg mx.controls.Text)
3. The dimensions of the container (eg the UIComponent that contains the Text/target) are then set to the  target's pixelBounds dimensions.
4.  Finally, take the snapshot bitmap of the container (the UIComponent).

My opinion is that the following is a big bug.

When serializing/cloning an object that has required constructor parameters, you receive an error telling you the arguments are incorrect. Note: the following is just an example using a "native" flash class. Really, you should never have to serialize or clone an Event, so please just see it as an example class as the type of class isn't the point.

[actionscript]
import flash.net.registerClassAlias;
import flash.events.Event;
import mx.utils.ObjectUtil;

flash.net.registerClassAlias("flash.events.Event",Event);
var event:Event = new Event(Event.CHANGE);
var eventClone:* = ObjectUtil.copy(event);
trace(eventClone is Event)
[/actionscript]

[result]
ArgumentError: Error #1063: Argument count mismatch on flash.events::Event(). Expected 1, got 0.
at flash.utils::ByteArray/readObject()
at mx.utils::ObjectUtil$/copy()
at Untitled_fla::MainTimeline/frame1()
[/result]

As noted by Nutrox, "All constructor parameters need a default value. You can't pass values directly to an object's constructor when it is restored from serialised data because Flash creates an instance of the object automatically before calling the object's readExternal() method."

Ever try to add a DisplayObject to a Flex Component? If you have, you know the run-time engine will complain about a type conversion (Adobe casts DisplayObjects to IUIComponents). Well, there is a hidden $addChild for UIComponents. To utilize simply add use namespace mx_internal; to the beginning of your script. Now you can use $addChild.

For more information, check out http://www.boostworthy.com/blog/?p=224.

I came across a bug where when you set the scrollRect of a DisplayObject and get a dimension, within the first few mil/nano-seconds it reports the correct width and height. However, after that the reported width and height is the scrollRect's width and height. This to me is a bug considering you can not request the object to tell you it's full dimensions any longer.

Take a look at http://www.kirupa.com/forum/archive/index.php/t-256884.html and here is the solution http://usecake.com/lab/find-the-height-and-width-of-a-sprite-with-a-scrollrect.html