### Portals

Portals are a very important tool to speed up the rendering of levels. Well defined sectors can greatly speed up rendering and allow various tricks, to understand what they are, read this guide.

CS uses portals to connect different sectors. A portal can be for example a door or a window that connects the interior of an house to the exterior. In that case the interior will be one sector, the exterior another one.
To add a portal to a 3dsmax scene follow this guidelines:

- the object name must start with "_p_" . For example "_p_laanx1" is a valid portal name.
- it MUST be a mesh with 2 planar triangle polygons (a square similar to a door is perfect).
- add a property to the object (see 'Objects' chapter for details on how to add a property) called "PORTAL" that points to the roomname of the sector where that portal will lead to.
  Example: PORTAL=plaza

Please note than the exporter will produce 1 sector per exported scene , so if you want to make a level with many sectors:

- Create different max scene (one per sector )
- Merge them to see if they fit correctly toghether
- Export each one separatly
- Merge the exported files. (PS team developed a simple tool for merging).

Next: Samples