bongiovi's

Recently I become very interested in light effects, and I found an amazing light effect on wonderfl:

yonatan challenge for people with nothing better to do - wonderfl build flash online

at the same time i come across the work of this amazing artist : http://alicexz.deviantart.com/ , then I saw this picture, it's so beautiful and i couldn't help thinking what will it be with the light effect i found? so i just give it a try, i remove the brighter part so it becomes transparent, where the light can come through, the result is very interesting, you can see it here or click on the image.

There is a trick when i was adding those particles, in fact all was drawn in a single BitmapData, to create a hole in a BitmapData you can use BitmapData.draw() method combine with BlendMode.ERASE, but here comes the tricky part : when you passing the object you wish to draw, it can't be a BitmapData, it must be a shape, a Bitmap or something else, like this :

bitmapData.draw(bitmapLattern, mtx, ct, BlendMode.ERASE, null, true); // working
bitmapData.draw(bitmapDataLattern, mtx, ct, BlendMode.ERASE, null, true); // not working

After testing this, i was fascinated by it, and i want to try it on a chinese painting, i took a vary famous painting of chinese : http://en.wikipedia.org/wiki/Along_the_River_During_the_Qingming_Festival

it's a very beautiful painting but also very big, so i can't preprocess it in PhotoShop and export an PNG, it will be too large, therefore i create a little Pixel Bender Program to do the task for me :

#define getLength(color) color.r*color.r + color.g*color.g + color.b*color.b                              

void
evaluatePixel() {               
   float2 pos = outCoord();
   float4 color = sampleLinear(src, pos);
   color.a = 1.0 - getLength(color)/3.0;
   dst = color;
}

so the brighter a pixel is, the more transparent it will be, you can check the result here, or click on the image as well.

P.S.  Both 2 take some time to load because the image is big, be patient