CairoSamples.Form1.gradientToolStripMenuItem_Click C# (CSharp) Метод

        private void gradientToolStripMenuItem_Click(object sender, EventArgs e)
        {
            lastSelected = "gradient";
            OnPaintAction = cr =>
            {
                Gradient pat = new LinearGradient(0.0, 0.0, 0.0, 256.0);
                pat.AddColorStopRgba(1, 0, 0, 0, 1);
                pat.AddColorStopRgba(0, 1, 1, 1, 1);
                cr.Rectangle(0, 0, 256, 256);
                cr.SetSource(pat);
                cr.Fill();
                pat.Dispose();

                pat = new RadialGradient(115.2, 102.4, 25.6,
                                         102.4, 102.4, 128.0);
                pat.AddColorStopRgba(0, 1, 1, 1, 1);
                pat.AddColorStopRgba(1, 0, 0, 0, 1);
                cr.SetSource(pat);
                cr.Arc(128.0, 128.0, 76.8, 0, 2 * Math.PI);
                cr.Fill();
                pat.Dispose();
            };

            Invalidate();
        }