public class voltm
    {
        System.Drawing.SolidBrush radiera;
        System.Drawing.Graphics zona_des;
        int x0;
        int y0;
        int w;
        double vm;
        public void desen_voltm(System.Drawing.Color culoare_gradatii, System.Drawing.Color culoare_valori)
        {
            System.Drawing.Pen creion = new System.Drawing.Pen(culoare_gradatii);
            System.Drawing.Font font_ni = new System.Drawing.Font("Nina", 8);
            System.Drawing.SolidBrush pens_blu = new System.Drawing.SolidBrush(culoare_valori);
            int lt = 15;
            int lg = 22;
            int x1, x2, xt, y1, y2, yt;
            int xc = x0 + w / 2;
            int yc = y0 + w / 2;
            int raza = w / 2;
            int nrd;
            int val_a = 0;
            // alfa_gr unghiul in grade
            double alfa_gr = 140;
            nrd = 0;
            zona_des.FillRectangle(radiera, xc - raza, yc - raza - 2, 2 * raza, 5 * raza / 4);

            while (alfa_gr >= 40)
            {
                double alfa_r = 2 * System.Math.PI * (alfa_gr) / 360;// unghiul in radiani
                if (nrd % 5 == 0)
                {
                    x1 = System.Convert.ToInt16(xc + (raza - lt) * System.Math.Cos(alfa_r));
                    y1 = System.Convert.ToInt16(yc - (raza - lt) * System.Math.Sin(alfa_r));
                    xt = System.Convert.ToInt16(xc - 5 + raza * System.Math.Cos(alfa_r));
                    yt = System.Convert.ToInt16(yc - raza * System.Math.Sin(alfa_r));
                    zona_des.DrawString(System.Convert.ToString(val_a), font_ni, pens_blu, xt, yt);
                    val_a = val_a + System.Convert.ToInt16(vm / 10);

                }
                else
                {
                    x1 = System.Convert.ToInt16(xc + (raza - lg) * System.Math.Cos(alfa_r));
                    y1 = System.Convert.ToInt16(yc - (raza - lg) * System.Math.Sin(alfa_r));
                }
                x2 = System.Convert.ToInt16(xc + (raza - 2 * lt) * System.Math.Cos(alfa_r));
                y2 = System.Convert.ToInt16(yc - (raza - 2 * lt) * System.Math.Sin(alfa_r));
                zona_des.DrawLine(creion, x1, y1, x2, y2);
                alfa_gr -= 2;
                nrd++;
            }
            zona_des.DrawRectangle(creion, xc - raza, yc - raza - 2, 2 * raza, 5 * raza / 4);
        }
        public void setval(double val, System.Drawing.Color culoare_ac)
        {
            System.Drawing.Pen creion = new System.Drawing.Pen(culoare_ac);
            int alfa_gr = 140 - System.Convert.ToInt16(100 * val / vm); ;//unghiul in grade
            int lg = 17;
            int xc = x0 + w / 2;
            int yc = y0 + w / 2;
            int raza = w / 2;
            zona_des.FillPie(radiera, x0 + 2 * lg - 1, y0 + 2 * lg - 1, w - 4 * lg + 2, w - 4 * lg + 2, 10, -180);
            double alfa_r = 2 * System.Math.PI * (alfa_gr) / 360;// unghiul in radiani
            int x = System.Convert.ToInt16(xc + (raza - 2 * lg) * System.Math.Cos(alfa_r));
            int y = System.Convert.ToInt16(yc - (raza - 2 * lg) * System.Math.Sin(alfa_r));
            zona_des.DrawLine(creion, x, y, xc, yc);
            alfa_gr = 40;
            zona_des.DrawRectangle(creion, xc - raza, yc - raza - 2, 2 * raza, 5 * raza / 4);
        }
        public voltm(System.Drawing.Graphics desen, int pozx, int pozy, int lat, double val_max, Color culoare_fundal)
        {
            zona_des = desen;
            radiera = new System.Drawing.SolidBrush(culoare_fundal);
            x0 = pozx;
            y0 = pozy;
            w = lat;
            vm = val_max;
        }
    }