it makes an icon's alpha value the same as intellij's one's. (I used it to make intellij plugin icon)

coping-alpha-of-intellij-icon.kt

import java.io.File
import javax.imageio.ImageIO

/**
 * Created by ice1000 on 2017/3/28.
 *
 * @author ice1000
 */


fun main(args: Array<String>) {
	val origin = ImageIO.read(File("lice.png"))
	val css = ImageIO.read(File("css.png"))
	val alphaPosition = 0xFF shl 24
	val bottomAlpha = css.getRGB(css.width - 1, css.height - 1) and alphaPosition
	(0..origin.width - 1).forEach { x ->
		(0..origin.height - 1).forEach { y ->
			val o = origin.getRGB(x, y)
			origin.setRGB(x, y,
					if (y < 9 || x < 1) css.getRGB(x, y)
					else o + bottomAlpha
			)
		}
	}
	ImageIO.write(origin, "PNG", File("lice-edited.png"))
}