Exporting Object as Proxy
From LuxRender Wiki
Exporting an Object as Proxy
In complex scenes, there are often highpoly objects that are no longer edited, but still needed in the viewport preview, thus slowing it down. In an architectural visualization, for example, there are trees, cars and people models that are only duplicated and placed in the scene, but their meshes are rarely edited after the creation process.
LuxBlend offers a tool to simplify these objects in the viewport while still using the original highpoly mesh while rendering: the "Export as Proxy" operator found in the File -> Export menu:
We start with this object, which has over 2 million polygons, a subsurf and a simple deform modifier.
Now we use the proxy export menu, choose a path to export the mesh to (preferably something like "sceneFolder/proxies/") and hit the export button. Depending on how complex the mesh is, the export may take a few minutes.
What we get after the export is this:
Note how the object was split into sub-objects by materials. These sub-objects are all parented to a bounding box object. The polycount of our scene is now down from 2 million to only 13 thousand faces. In the object settings, you will find that the "use as proxy" option is enabled and the path to the exported mesh is automatically set.
Now we can happily duplicate, scale, rotate the proxy objects:
For LuxRender, there is no difference between a normally exported object and a proxy object. This is the original mesh rendered with Lux:
While this is the render of the scene after proxy export:
Note how the geometry is smooth and highpoly, just as in the original scene.