Only in bitmapdata
________________________________ From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Josh McDonald Sent: Wednesday, February 20, 2008 11:46 AM To: [email protected] Subject: Re: [flexcoders] Re: Transparent=true on BitmapData not working So the colour value is a 32 bi argb instead of just 24 bit rgb then? Well that makes sense :) Where else in flex is a colour value 32 bit instead of 24 bit? Is it all over the place and I've just never noticed? What about in styles? -J On Thu, Feb 21, 2008 at 3:39 AM, Troy Gilbert <[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> > wrote: > Just plain old 0 worked fine. I just went back and checked the docs, they do > actually tell you to do that, but I doubt I ever would have seen it. Doesn't > really make sense, but you get that :) Actually, it makes perfect sense. The default value for the fill color is 100% white with 100% alpha (fully opaque), which is 0xffffffff in ARGB format. You want it to be blank/transparent, so you need to provide a default fill color that has 0% alpha, so anything of the form 0x00??????. Using black with zero-alpha is good habit because it's equivalent to pre-multiplying your colors with black, which is what works best (or at least most intuitively) with standard computer blending equations. The true/false flag just controls whether or not your BitmapData *has* an alpha channel, not what the contents of that alpha channel are (the docs should probably be clearer about this and the argument should probably be named "hasAlphaChannel" as opposed to "transparency", just to be more explicit). Basically, this flag controls whether your data is ARGB or RGB (though I wouldn't be surprised if they were both stored as 32-bits-per-pixel as that normally speeds up blitting since the pixels are word-aligned). Troy. -- "Therefore, send not to know For whom the bell tolls, It tolls for thee." :: Josh 'G-Funk' McDonald :: 0437 221 380 :: [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>
