docs: private static Shader createRadialGradient(@NonNull final Orientation orientation,
                                                 final int bitmapSize, final float radius) {
          PointF center = new PointF();
  
          switch (orientation) {
              case TOP_LEFT:
                  center.x = bitmapSize;
                  center.y = bitmapSize;
                  break;
              case TOP_RIGHT:
                  center.y = bitmapSize;
                  break;
              case BOTTOM_LEFT:
                  center.x = bitmapSize;
                  break;
              case BOTTOM_RIGHT:
                  break;
              default:
                  throw new IllegalArgumentException("Invalid orientation: " + orientation);
          }
  
          return new RadialGradient(center.x, center.y, radius, Color.TRANSPARENT, Color.BLACK,
                  Shader.TileMode.CLAMP);
      }