Comments on: Get first non transparent pixel in a bitmap, 3 approaches and benchmarks http://www.sakri.net/blog/2009/02/10/get-first-non-transparent-pixel-in-a-bitmap-3-approaches-and-benchmarks/ I Flash und I Flex Jaaaa Thu, 11 Mar 2010 18:59:59 +0000 http://wordpress.org/?v=2.6.2 By: sakri http://www.sakri.net/blog/2009/02/10/get-first-non-transparent-pixel-in-a-bitmap-3-approaches-and-benchmarks/#comment-812 sakri Wed, 18 Feb 2009 09:29:11 +0000 http://www.sakri.net/blog/?p=170#comment-812 You probably explained it right, I just didn't understand :) I'll give that a go... sounds good! Thanks Mario! You probably explained it right, I just didn’t understand :)

I’ll give that a go… sounds good! Thanks Mario!

]]> By: Mario Klingemann http://www.sakri.net/blog/2009/02/10/get-first-non-transparent-pixel-in-a-bitmap-3-approaches-and-benchmarks/#comment-811 Mario Klingemann Tue, 17 Feb 2009 15:00:23 +0000 http://www.sakri.net/blog/?p=170#comment-811 Hmm - sounds like you misunderstood something that I said back then. The way I find the first non-transparent pixel is by using to consecutive applications of getColorBoundsRect(): - step one: use getColorBoundsRect(0xff000000,0,false) on the bitmap you want to find the pixel - step two: create a transparent 1 pixel high bitmap with the width of the colorbounds rect that you've found - step three: use copyPixels to copy the first row of the found rect into the the 1 pixel bitmap - step four: use another getColorBoundsRect(0xff000000,0,false) on the 1 pixel bitmap -> add the x property of that rect to the x property of the first color rect's topLeft point and you have the first non-transparent point I guess I should add a post to my blog with an example.... Hmm - sounds like you misunderstood something that I said back then. The way I find the first non-transparent pixel is by using to consecutive applications of getColorBoundsRect():

- step one: use getColorBoundsRect(0xff000000,0,false) on the bitmap you want to find the pixel
- step two: create a transparent 1 pixel high bitmap with the width of the colorbounds rect that you’ve found
- step three: use copyPixels to copy the first row of the found rect into the the 1 pixel bitmap
- step four: use another getColorBoundsRect(0xff000000,0,false) on the 1 pixel bitmap
-> add the x property of that rect to the x property of the first color rect’s topLeft point and you have the first non-transparent point

I guess I should add a post to my blog with an example….

]]>