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    <p>You see points because you are drawing points with <code>glBegin(GL_POINTS)</code>. Try replacing it by <code>glBegin(GL_LINE_STRIP)</code>.</p> <p><strong>NOTE:</strong> when you saw the circle you also drew only points, but drawn close enough to appear as a connected circle.</p> <p>Also, you may have not setup the depth buffer to accept values in the range z = [-50, 310] that you use. These arguments should be provided as <em>zNear</em> and <em>zFar</em> clipping planes in your <code>gluPerspective</code>, <code>glOrtho()</code> or <code>glFrustum()</code> call.</p> <p><strong>NOTE:</strong> this would explain why with z value you only see a few points: the other points are clipped because they are outside the z-buffer range.</p> <p><strong>UPDATE AFTER YOU HAVE SHOWN YOUR CODE:</strong></p> <p><code>glOrtho(-100*aspectratio,100*aspectratio,-100,100,1,-1);</code> would only allow z-values in the [-1, 1] range, which is why only the three points with <code>z = -1</code>, <code>z = 0</code> and <code>z = 1</code> will be drawn (thus 3 points).</p> <p>Finally, you're probably viewing the spiral from the top, looking directly in the direction of the rotation axis. If you are not using a perspective projection (but an isometric one), the spiral will still show up as a circle. You might want to change your view with <code>gluLookAt()</code>.</p> <p><strong>EXAMPLE OF SETTING UP PERSPECTIVE</strong></p> <p>The following <a href="http://nehe.gamedev.net/data/lessons/lesson.asp?lesson=01" rel="noreferrer">code</a> is taken from the excellent OpenGL tutorials by NeHe:</p> <pre><code>glViewport(0, 0, width, height); glMatrixMode(GL_PROJECTION); // Select The Projection Matrix glLoadIdentity(); // Reset The Projection Matrix // Calculate The Aspect Ratio Of The Window gluPerspective(45.0f,(GLfloat)width/(GLfloat)height,0.1f,100.0f); glMatrixMode(GL_MODELVIEW); // Select The Modelview Matrix glLoadIdentity(); // Reset The Modelview Matrix </code></pre> <p>Then, in your <a href="http://nehe.gamedev.net/data/lessons/lesson.asp?lesson=02" rel="noreferrer">draw loop</a> would look something like this:</p> <pre><code>glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear The Screen And The Depth Buffer glLoadIdentity(); glTranslatef(-1.5f,0.0f,-6.0f); // Move Left 1.5 Units And Into The Screen 6.0 glBegin(GL_TRIANGLES); // Drawing Using Triangles glVertex3f( 0.0f, 1.0f, 0.0f); // Top glVertex3f(-1.0f,-1.0f, 0.0f); // Bottom Left glVertex3f( 1.0f,-1.0f, 0.0f); // Bottom Right glEnd(); </code></pre> <p>Of course, you should alter this example code your needs.</p>
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