Very pretty! For all who are afraid of curves, there are ways to do a whole circle on a square block, fused or other ways, then you cut it in four, to end up with DP blocks. Not sure what was done on this quilt, but am betting something similar.
Now me, I love doing this block & I would say, if it scares you, just try doing some, & trust me, you will more than likely overcome your fear of curves...