 ratio between on-screen pixels and the physics engine's meters.
A float describing the current PPM ratio.
</p><br/><h3>Read-Only Property:</h3><h2>MPP</h2><p>
The ratio between the physics engine's meters and on-screen pixels.
A float describing the current MPP ratio.
</p><br/><h3>Read-Only Property:</h3><h2>PPL</h2><p>
The ratio between the on-screen pixels and the physics engine's
Litres.
A float describing the current PPL ratio.
</p><br/><h3>Read-Only Property:</h3><h2>LPP</h2><p>
The ratio between the 