Get bitmap shader circle img

ImgRedactor

    // Get bitmap shader circle img
    public static Bitmap getCircleMaskedBitmapShader(Bitmap source, int radius) {
        if (source == null) { return null; }

        int diam = radius << 1;

        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);

        Bitmap scaledBitmap = scaleTo(source, diam);
        final Shader shader = new BitmapShader(scaledBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
        paint.setShader(shader);

        Bitmap targetBitmap = Bitmap.createBitmap(diam, diam, Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(targetBitmap);
        canvas.drawCircle(radius, radius, radius, paint);

        return targetBitmap;
    }

    private static Bitmap scaleTo(Bitmap source, int size) {
        int destWidth = source.getWidth();
        int destHeight = source.getHeight();

        destHeight = destHeight * size / destWidth;
        destWidth = size;

        if (destHeight < size) {
            destWidth = destWidth * size / destHeight;
            destHeight = size;
        }

        Bitmap destBitmap = Bitmap.createBitmap(destWidth, destHeight, Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(destBitmap);
        canvas.drawBitmap(source, new Rect(0, 0, source.getWidth(), source.getHeight()), new Rect(0, 0, destWidth, destHeight), new Paint(Paint.ANTI_ALIAS_FLAG));
        return destBitmap;
    }