OpenGL Draw Helix

1. Figure:

2. Code

/** * @ description use OpenGL to draw Helix * @ Project Name APP_OPENGL * @ Package Name Com.android.opengl * @ class name spiralmainactivity * @author Chenlin * @da TE May 12, 2014 PM 10:57:20 * @version 1.0 */public class Spiralmainactivity extends Activity {private static float
    ANGLE = -90f;
    private static float pos_x = 1f;
    private static float pos_y = 0f;

    private static float pos_z = 0f;
        @Override protected void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);
        Myglsurfaceview Surfaceview = new Myglsurfaceview (this);
        Surfaceview.setrenderer (New Myrender ());
    Setcontentview (Surfaceview); } private class Myglsurfaceview extends Glsurfaceview {public Myglsurfaceview (context context, AttributeSet
        Attrs) {Super (context, attrs);
        } public Myglsurfaceview (context context) {super (context); }}/** * Change position according to key */@Override public boolean onKeyDown (int keycode,KeyEvent event) {float step = 0.5f;
        Determine the key if (keycode = = keyevent.keycode_dpad_up) {pos_x = Pos_x-step;

        } else if (keycode = = Keyevent.keycode_dpad_down) {pos_x = pos_x + step;

        } else if (keycode = = keyevent.keycode_dpad_left) {pos_y = Pos_y-step;

        } else if (keycode = = keyevent.keycode_dpad_right) {pos_y = pos_y + step;
    } return Super.onkeydown (KeyCode, event);

        } Private class Myrender implements Renderer {private float mratio; The surface is created @Override public void onsurfacecreated (GL10 gl, EGLConfig config) {//R,g,b,alph
            A) Gl.glclearcolor (0f, 0f, 0f, 1f);
        Enable array of vertex buffers gl.glenableclientstate (Gl10.gl_vertex_array);
            }//Surface size @Override public void onsurfacechanged (GL10 gl, int width, int height) { Gl.glviewport (0, 0, width, height);
            Mratio = width * 1.0f/height;
            Gl.glmatrixmode (gl10.gl_projection);
            Gl.glloadidentity ();
        GL.GLFRUSTUMF ( -1f, 1f,-mratio, Mratio, 3f, 7f); }//Drawing @Override public void Ondrawframe (GL10 gl) {//Clear color buffers Gl.glclea
            R (Gl10.gl_color_buffer_bit);
            Set the drawing color gl.glcolor4f (1f, 0f, 0f, 1f);
            Operation Model Matrix Gl.glmatrixmode (Gl10.gl_modelview);
            Gl.glloadidentity ();

            Set the eye observation point Glu.glulookat (GL, 0f, 0f, 5f, 0f, 0f, 0f, 0f, 1f, 0f);
            Rotary//Gl.glrotatef ( -90f, 1, 0, 0);

            Gl.glrotatef (ANGLE, pos_x, pos_y, pos_z);
            Draw Circular Float R = 0.5f;//radius list<float> coordslist = new arraylist<float> ();
            Defines the center coordinate of float x = 0f, y = 0f, z = 1.5f;
            float zstep = 0.01f; for (Float i = 0f; I < Math.PI * 6;
                i = (float) (i + math.pi/32)) {//get rotated at coordinates x = (float) (R * Math.Cos (i));
                y = (float) (R * Math.sin (i));
                z = z-zstep;
                Coordslist.add (x);
                Coordslist.add (y);
            Coordslist.add (z);
            } bytebuffer bb = Bytebuffer.allocatedirect (Coordslist.size () * 4);
            Bb.order (Byteorder.nativeorder ());
            Floatbuffer fb = Bb.asfloatbuffer ();
            for (float f:coordslist) {fb.put (f);
            } bb.position (0);
            Specifies the vertex pointer gl.glvertexpointer (3, gl10.gl_float, 0, BB);
        Plot the number of points gl.gldrawarrays (gl10.gl_points, 0, Coordslist.size ()/3); }

    }
}

3. Drawing a picture