Radegast.Rendering.SceneWindow.RenderSphere C# (CSharp) Method

        void RenderSphere(float cx, float cy, float cz, float r, int p)
        {
            GL.PushAttrib(AttribMask.AllAttribBits);
            GL.Disable(EnableCap.Fog);
            GL.Disable(EnableCap.Texture2D);
            GL.Disable(EnableCap.Dither);
            GL.Disable(EnableCap.Lighting);
            GL.Disable(EnableCap.LineStipple);
            GL.Disable(EnableCap.PolygonStipple);
            GL.Disable(EnableCap.CullFace);
            GL.Disable(EnableCap.Blend);
            GL.Disable(EnableCap.AlphaTest);
            GL.Disable(EnableCap.DepthTest);

            const float TWOPI = 6.28318530717958f;
            const float PIDIV2 = 1.57079632679489f;

            float theta1 = 0.0f;
            float theta2 = 0.0f;
            float theta3 = 0.0f;

            float ex = 0.0f;
            float ey = 0.0f;
            float ez = 0.0f;

            float px = 0.0f;
            float py = 0.0f;
            float pz = 0.0f;

            // Disallow a negative number for radius.
            if (r < 0)
                r = -r;

            // Disallow a negative number for precision.
            if (p < 0)
                p = -p;

            // If the sphere is too small, just render a OpenGL point instead.
            if (p < 4 || r <= 0)
            {
                GL.Begin(PrimitiveType.Points);
                GL.Vertex3(cx, cy, cz);
                GL.End();
                return;
            }

            for (int i = 0; i < p / 2; ++i)
            {
                theta1 = i * TWOPI / p - PIDIV2;
                theta2 = (i + 1) * TWOPI / p - PIDIV2;

                GL.Begin(PrimitiveType.TriangleStrip);
                {
                    for (int j = 0; j <= p; ++j)
                    {
                        theta3 = j * TWOPI / p;

                        ex = (float)(Math.Cos(theta2) * Math.Cos(theta3));
                        ey = (float)Math.Sin(theta2);
                        ez = (float)(Math.Cos(theta2) * Math.Sin(theta3));
                        px = cx + r * ex;
                        py = cy + r * ey;
                        pz = cz + r * ez;

                        GL.Normal3(ex, ey, ez);
                        GL.TexCoord2(-(j / (float)p), 2 * (i + 1) / (float)p);
                        GL.Vertex3(px, py, pz);

                        ex = (float)(Math.Cos(theta1) * Math.Cos(theta3));
                        ey = (float)Math.Sin(theta1);
                        ez = (float)(Math.Cos(theta1) * Math.Sin(theta3));
                        px = cx + r * ex;
                        py = cy + r * ey;
                        pz = cz + r * ez;

                        GL.Normal3(ex, ey, ez);
                        GL.TexCoord2(-(j / (float)p), 2 * i / (float)p);
                        GL.Vertex3(px, py, pz);
                    }
                }
                GL.End();
            }
            GL.PopAttrib();
        }