Archive for January, 2008

Multi Gradient

January 24, 2008 at 2:52 am · Filed under Graphics, source, BitmapData, AS3

It’s a gradient created from the corners of the square.
I was googling and I found the Diamond-Square on Wikipedia.

The idea is quite simple.
First you get the top left and bottom left corner colors of the square. Than, you get the half height of the edge and also the average color of those colors.
You repeat that until you have all pixels of the edge.

Note: The average color is not (color2 - color1) * .5.
It’s (color2.r - color1.r) * .5 << 16 + (color2.g - color1.g) * .5 << 8 + (color2.b - color1.b) * .5.

After that, you make the same with the right edge.

Than, you do it for each edge from the top to bottom.

If you work around more, you can create gradient spots from any pixel you wish easily.

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Grayscale Converter

January 19, 2008 at 3:00 am · Filed under Graphics, source, BitmapData, AS3

Answering to CK

1.
ck said,

January 14, 2008 @ 8:07 pm · Edit

… you mentioned to use BitmapData.paletteMap() to generate a grayscale image. Until now I didn’t get this working. How did you do that?

You can convert a BitmapData to Grayscale easily without using my ColorUtils class.

import br.hellokeita.utils.ColorUtils;

…

var bmpData:BitmapData = new BitmapData(w, h);

…

var grayscaleArray:Array = new Array();
var c:Number;
for(var i = 0; i < 0xff; i++){
       
        c = i * .3 + i * .59 + i * .11;
        grayscaleArray[i] = (c<<16) + (c<<8) + c;
       
}

bmpData.paletteMap(bmpData, bmpData.rect, new Point(0,0), grayscaleArray, grayscaleArray, grayscaleArray);

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