BlenderImport(3pm)					User Contributed Perl Documentation					BlenderImport(3pm)

NAME

       XRacer::BlenderImport - Import files exported by xracer-blenderexport.py

SYNOPSIS

	 use XRacer::BlenderImport;

	 $world = parse XRacer::BlenderImport [ $filename ];

	 $index = $world->add_vertex ($vertex);
	 $verticesref = $world->get_vertices;
	 %layerinfo = $world->get_layer_info;

	 @objects = $world->get_meshes_in_layer ($layer);

DESCRIPTION

       The "XRacer::BlenderImport" module contains functions for importing special XRacer-specific Blender files into Perl scripts.  These Blender
       files have been previously exported by the "xracer-blenderexport.py" Python script for Blender.

       The "XRacer::BlenderImport" module parses the "blender.export" file, cleans it up (removing multiple vertices, for example) and presents an
       internal world representation. The world is divided into layers (corresponding to the layers in the original Blender image), and in each of
       these layers is a set of meshes.

   FUNDAMENTAL TYPES
       Vertices are stored in a global list, so that common vertices are only stored once. A vertex structure looks like this:

	 $vertex = { coords => [ $x, $y, $z, 0 ],
		     texcoords => [ $u, $v ],
		     normal => [ $nx, $ny, $nz, 0 ],
		     colour => [ $r, $g, $b, $a ] };

       The fields are (in order): the coordinates of the vertex, the texture coordinates, the normal vector at this point and the colour of the
       vertex.

       Faces are stored simply as a list of vertex indices (relative to the global list of vertices). A face looks like this:

	 $face = { vertices => [ $index0, $index1, $index2, ... ] }

       Faces have at least three vertices, and maybe more.

       A mesh is a list of faces and additional information, such as the name of the mesh (object). A mesh structure looks like this:

	 $mesh = { name => $name,
		   layer => $layer,
		   faces => @faces,
		   material => [ $red, $green, $blue ],
		   has_colours => $has_colours,
		   has_texcoords => $has_texcoords,
		   has_material => $has_material };

       The fields are: the name of the mesh (or object), the layer on which the object exists, the list of faces, the material and then three
       flags which are passed to us from Blender: did the user supply vertex colours? did the user supply texture coordinates? and did the user
       supply a material?

CLASS METHODS

       $world = parse XRacer::BlenderImport [ $filename ];
	   Parse the import file $filename (or "blender.export" if no filename is given) and generate a world representation.  If the file could
	   not be parsed, then this function will print an error message and return "undef".

OBJECT METHODS

       $index = $world->add_vertex ($vertex)
	   This function adds a single vertex to the world object (vertices are stored in a large shared list so that common vertices are folded
	   into one). It returns the vertex index of the new vertex.  If another vertex with the same position, texture coordinates, normal and
	   colour existed, then this function would return the index of the other vertex, rather than creating a fresh vertex object.

       $verticesref = $world->get_vertices
	   This returns a reference to the global list of vertices. You must not update or change this list. Use the "add_vertex" method instead.

       %layerinfo = $world->get_layer_info
	   This method returns a hash. The keys of the hash are layers which contain at least one object. The values of the hash are the number of
	   objects in that layer.

	   For example, if the world contained 3 objects on layer 1, 1 object on layer 2 and 4 objects on layer 5, then the hash returned would be
	   equivalent to:

	     %layerinfo = ( 1 => 3, 2 => 1, 5 => 4 );

       @objects = $world->get_meshes_in_layer ($layer)
	   Get a list of the objects (i.e. meshes) found in layer $layer.  See the DESCRIPTION section above for a description of the mesh
	   structure.

AUTHOR

	 Richard W.M. Jones, <rich@annexia.org>

COPYRIGHT

       XRacer is copyright (C) 1999-2000 Richard W.M. Jones (rich@annexia.org) and other contributors listed in the AUTHORS file.

SEE ALSO

       perl(1), xracer(6).

perl v5.14.2							    2000-01-30							BlenderImport(3pm)