libGDX图片磨砂玻璃效果

import com.badlogic.gdx.graphics.Pixmap;

public class Blur {

	public static void blurImage(int radius, Pixmap pixmap, int width,
			int height, int rectx, int recty, int rectw, int recth) {
		int w = pixmap.getWidth();
		int h = pixmap.getHeight();

		int xoffset = 0;
		int yoffset = 0;

		if (width > w) {
			width = w;
		}
		if (height > h) {
			height = h;
		}

		w = width;
		h = height;

		if (rectx > width) {
			rectx = 0;
		}
		if (recty > height) {
			recty = 0;
		}

		if (rectx + rectw > width) {
			rectw = width - rectx;
		}
		if (recty + recth > height) {
			recth = height - recty;
		}

		xoffset = rectx;
		yoffset = recty;

		w = rectw;
		h = recth;
		// mwxx red border around
		//pixmap.setColor(1, 0, 0, 1);
		pixmap.drawRectangle(xoffset, yoffset, w, h);

		int wm = w - 1;
		int hm = h - 1;
		int wh = w * h;
		int div = radius + radius + 1;

		int r[] = new int[wh];
		int g[] = new int[wh];
		int b[] = new int[wh];
		int rsum, gsum, bsum, x, y, i, p, yp, yi, yw;
		int vmin[] = new int[(int) Math.max(w, h)];

		int divsum = (div + 1) >> 1;
		divsum *= divsum;
		int dv[] = new int[256 * divsum];
		for (i = 0; i < 256 * divsum; i++) {
			dv[i] = (i / divsum);
		}

		yw = yi = 0;

		int[][] stack = new int[div][3];
		int stackpointer;
		int stackstart;
		int[] sir;
		int rbs;
		int r1 = radius + 1;
		int routsum, goutsum, boutsum;
		int rinsum, ginsum, binsum;

		for (y = 0; y < h; y++) {
			rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
			for (i = -radius; i <= radius; i++) {

				int index = yi + Math.min(wm, (int) Math.max(i, 0));

				int yy = (int) (index / w);
				int xx = (int) (index % h);

				// 32-bit RGBA8888
				p = pixmap.getPixel(xx + xoffset, yy + yoffset);

				int mask = p & 0xFFFFFFFF;
				int rr = (mask >> 24) & 0xff;
				int gg = (mask >> 16) & 0xff;
				int bb = (mask >> 8) & 0xff;

				sir = stack[i + radius];

				sir[0] = rr;
				sir[1] = gg;
				sir[2] = bb;

				rbs = r1 - (int) Math.abs(i);
				rsum += sir[0] * rbs;
				gsum += sir[1] * rbs;
				bsum += sir[2] * rbs;
				if (i > 0) {
					rinsum += sir[0];
					ginsum += sir[1];
					binsum += sir[2];
				} else {
					routsum += sir[0];
					goutsum += sir[1];
					boutsum += sir[2];
				}
			}
			stackpointer = radius;

			for (x = 0; x < w; x++) {

				r[yi] = dv[rsum];
				g[yi] = dv[gsum];
				b[yi] = dv[bsum];

				rsum -= routsum;
				gsum -= goutsum;
				bsum -= boutsum;

				stackstart = stackpointer - radius + div;
				sir = stack[stackstart % div];

				routsum -= sir[0];
				goutsum -= sir[1];
				boutsum -= sir[2];

				if (y == 0) {
					vmin[x] = Math.min(x + radius + 1, wm);
				}
				int index = yw + vmin[x];

				int yy = (int) (index / w);
				int xx = (int) (index % h);

				// 32-bit RGBA8888
				p = pixmap.getPixel(xx + xoffset, yy + yoffset);

				int mask = p & 0xFFFFFFFF;
				int rr = (mask >> 24) & 0xff;
				int gg = (mask >> 16) & 0xff;
				int bb = (mask >> 8) & 0xff;

				sir[0] = rr;
				sir[1] = gg;
				sir[2] = bb;

				rinsum += sir[0];
				ginsum += sir[1];
				binsum += sir[2];

				rsum += rinsum;
				gsum += ginsum;
				bsum += binsum;

				stackpointer = (stackpointer + 1) % div;
				sir = stack[(stackpointer) % div];

				routsum += sir[0];
				goutsum += sir[1];
				boutsum += sir[2];

				rinsum -= sir[0];
				ginsum -= sir[1];
				binsum -= sir[2];

				yi++;
			}
			yw += w;
		}
		for (x = 0; x < w; x++) {
			rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
			yp = -radius * w;
			for (i = -radius; i <= radius; i++) {
				yi = (int) Math.max(0, yp) + x;

				sir = stack[i + radius];

				sir[0] = r[yi];
				sir[1] = g[yi];
				sir[2] = b[yi];

				rbs = r1 - (int) Math.abs(i);

				rsum += r[yi] * rbs;
				gsum += g[yi] * rbs;
				bsum += b[yi] * rbs;

				if (i > 0) {
					rinsum += sir[0];
					ginsum += sir[1];
					binsum += sir[2];
				} else {
					routsum += sir[0];
					goutsum += sir[1];
					boutsum += sir[2];
				}

				if (i < hm) {
					yp += w;
				}
			}
			yi = x;
			stackpointer = radius;
			for (y = 0; y < h; y++) {
				int rr = dv[rsum];
				int gg = dv[gsum];
				int bb = dv[bsum];

				pixmap.setColor(rr / 255f, gg / 255f, bb / 255f, 1f);

				int yy = (int) (yi / w);
				int xx = (int) (yi % h);
				pixmap.drawPixel(xx + xoffset, yy + yoffset);

				rsum -= routsum;
				gsum -= goutsum;
				bsum -= boutsum;

				stackstart = stackpointer - radius + div;
				sir = stack[stackstart % div];

				routsum -= sir[0];
				goutsum -= sir[1];
				boutsum -= sir[2];

				if (x == 0) {
					vmin[y] = Math.min(y + r1, hm) * w;
				}
				p = x + vmin[y];

				sir[0] = r[p];
				sir[1] = g[p];
				sir[2] = b[p];

				rinsum += sir[0];
				ginsum += sir[1];
				binsum += sir[2];

				rsum += rinsum;
				gsum += ginsum;
				bsum += binsum;

				stackpointer = (stackpointer + 1) % div;
				sir = stack[stackpointer];

				routsum += sir[0];
				goutsum += sir[1];
				boutsum += sir[2];

				rinsum -= sir[0];
				ginsum -= sir[1];
				binsum -= sir[2];

				yi += w;
			}
		}
	}
}