= !PseudoLoader =
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A !PseudoLoader is a type of !OpenSceneGraph [http://www.openscenegraph.org/documentation/OpenSceneGraphReferenceDocs/a02205.html osgDB] !PlugIn.

It differs from a typical ReferenceGuides/OsgDB file-loading plugin in that the "filename" string does not correspond to an actual file on disk, but rather the string represents parameter information for the plugin code.  Thus a "pseudoloader" can be thought of as a plugin that processes "pseudo-filenames".

The main advantage of !PseudoLoaders is they may be used to extend any OSG application that uses [http://www.openscenegraph.org/documentation/OpenSceneGraphReferenceDocs/a02205.html osgDB's] dynamic plugin discovery mechanism.  That means that any application can be extended by a !PseudoLoader's capabilities with no change to the application's source code.

The core OSG currently has 3 !PseudoLoaders (see the plugin source code for more documentation):
 * .trans - translates a model file by some XYZ offset; example: `osgviewer cow.osg.0,0,10.trans`
 * .rot - rotates a model file about the XYZ axes; example: `osgviewer cow.osg.90,0,0.rot`
 * .scale - scales a model file; example: `osgviewer cow.osg.5.scale`

The [http://mew.cx/osg/#osgToy osgToy] package exposes most of its functionality as !PseudoLoaders, such as:
 * `osgviewer 3.sponge` : creates a level-3 [http://en.wikipedia.org/wiki/Menger_sponge Menger sponge] fractal
 * `osgviewer 20000.lorenz` : creates 20000 points of a [http://en.wikipedia.org/wiki/Lorenz_attractor Lorenz attractor]
 * `osgviewer cow.osg.spin` : animates a model with a simple rotation, like a pirouette.
 * `osgviewer cow.osg.drawnorm` : renders the model with linesegments representing the normals.
 * `osgviewer cow.osg.20.simplifier` : reduces a model to 20 percent of its original complexity.