bar radius not rendered correctly on inverted axis

[netil]

Description

radius isn't rendered correctly for each bar shape.

Steps to check or reproduce

bb.generate({
  data: {
    columns: [
	["data1", 80, 250, -200, 200, 250, 150],
	["data2", 170, -350, 240, 200, -250, 150],
	["data3", -120, 100, 240, -300, 350, 350],
	["data4", 180, 130, 340, 200, 250, -250]
    ],
    type: "bar"
  },
  axis: {
    rotated: true,
    y: {
      inverted: true
    }
  },
  bar: {
    radius: {
      ratio: 0.5
    }
  }
});