About operation order

The following list is the order of operations in which a filters array, blend modes, color transforms, and mask layers are attached or performed for a movie clip instance:

The movie clip's bitmap is updated from vector content (the cacheAsBitmap property is set to true).
If you use the setMask() method, and the mask has a bitmap cache, Flash performs an alpha blend between the two images.
Filters are then applied (blur, drop shadow, glow, and so on.)
If you use the ColorTransform class, the color transform operation is performed and cached as bitmap result.
If you apply a blending mode, the blend is then performed (using a vector renderer).
If you apply external masking layers, the layers perform masking (using a vector renderer).

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