title: What 3d engine should I choose?
body: <p>I'd like to do some air pollution simulation in three dimension. Some key features are:</p>
  
  <ol>
  <li>large amount of data</li>
  <li>better if it supports particle systems</li>
  <li>better if it combines terrains and buildings and air. That is, there are interactions between them.</li>
  <li>better if it can be run on web.</li>
  </ol>
  
  <p><strong>EDIT:</strong></p>
  
  <p>Language can be C++, C#, or python. Engines I know so far are like <strong>OpensSourceGraph</strong>, <strong>Ogre</strong>, <strong>Open Inventor</strong>, but I don't know the exact differences among them. <strong>Unity3D</strong> is a good choice for web 3D, but I'm not sure if it supports large amount of data. Besides, I have tried with <strong>OpenSim</strong> for a while, but it seems to not support particle systems and the data structure is not flexible enough.</p>