Applies a gaussian blur to the drawable, with specified radius of affect. The standard deviation of the normal distribution used to modify pixel values is calculated based on the supplied radius. This radius can be specified indepently on for the horizontal and the vertical direction. The RLE gaussian blurring performs most efficiently on computer-generated images or images with large areas of constant intensity. Values for radii less than 1.0 would generate spurious results. Therefore they are interpreted as 0.0, which means that the computation for this orientation is skipped.