class PieChartSectionData {
  // ...
  final double sectionOffset;
  // ...
}

class PieChartPainter {
  // ...
  void drawSections(...) {
      final section = data.sections[i];
      if (section.value == 0) {
        continue;
      }
      final sectionDegree = sectionsAngle[i];

      // Compute offset for "exploded" sections
      final sectionCenterAngle = tempAngle + (sectionDegree / 2);
      final sectionOffset = section.sectionOffset;
      final offsetDx =
          math.cos(Utils().radians(sectionCenterAngle)) * sectionOffset;
      final offsetDy =
          math.sin(Utils().radians(sectionCenterAngle)) * sectionOffset;
      final sectionCenter = center.translate(offsetDx, offsetDy);
      // ...
  }
}