Tip#12
The position of MovieClips dragged on to the stage is based on their dimensions. When attached with Actionscript it’s based on the movieClips origin.
For example if I have a simple box shape within a MovieClip. If I open up the MovieClip there should be a box shape. If the position of the shape was _x = -10 and y = 0 so the box is 10 pixels left of the origin(0,0). Were I do drag this MovieClip to the stage and set it’s position to (0,0) it would line up perfectly with stages top left corner despite actually being offset. This being the case I might assume that in order to attach the box movieClip to appear in the same position I would set it’s _x and _y properties to 0. This would wrong since attached MovieClips are attached based on there origin location. In this case the box would appear 10 pixels to the left of stage.
This is why it’s good practice to always have any move clips aligned to the origin so that no content goes beyond the x and y boundaries.
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