MissionPlanner.GridUI.CalcHeadingHold C# (CSharp) Method

        private void CalcHeadingHold()
        {
            int previous = (int)Math.Round(Convert.ToDecimal(((UpDownBase)NUM_angle).Text)); //((UpDownBase)sender).Text
            int current = (int)Math.Round(NUM_angle.Value);

            int change = current - previous;
            
            if (change > 0) // Positive change
            {
                int val = Convert.ToInt32(TXT_headinghold.Text) + change;
                if (val > 359) 
                {
                    val = val - 360;
                }
                TXT_headinghold.Text = val.ToString();
            }

            if (change < 0) // Negative change
            {
                int val = Convert.ToInt32(TXT_headinghold.Text) + change;
                if (val < 0)
                {
                    val = val + 360;
                }
                TXT_headinghold.Text = val.ToString();
            }
        }