title: how to draw line in 3D coordinates by android canvas?
body: <p>i want to draw some lines in 3D space to indicate a simple structure , how can i do that with <code>canvas</code> ?</p>
  
  <p>for now the only way that i think could work is using isometric formula to draw 3D shape (just like on paper) but in this case back lines might be draw on front lines instead of under them.</p>
  
  <p>is there any way to draw it with <code>Camera</code> ? and how?</p>
  
  <p>i tried this already:</p>
  
  <pre class="lang-java prettyprint-override"><code>Matrix matrix = new Matrix();
  canvas.drawLine(0,Im.getHeight(),Im.getWidth(),0,paint);
  Camera mCamera = new Camera();
  
  mCamera.rotateY(45);
  mCamera.getMatrix(matrix);
  
  matrix.preTranslate(-30, -100);
  matrix.postTranslate(30, 100);
  canvas.concat(matrix);
  </code></pre>
  
  <p>but the result is exactly same as :</p>
  
  <pre class="lang-java prettyprint-override"><code>canvas.drawLine(0,Im.getHeight(),Im.getWidth(),0,paint);
  </code></pre>