lodestar [options] inputfile
Place the output in file with name outputfile. If you do not specify this parameter the program generates an output filename by inserting some characters into the input filename. By default ".lod" will be inserted before the ".wrl" extension, if the option -n is specified ".opt" will be inserted and if the option -x is specified the number of the LOD to extract will be inserted.
(-v | --verbose) section['+'section]*
Causes the program to print out information to stdout. You can specify one or more sections separated by '+' (no spaces!). The following values are allowed for section:
| coord | information related to Coordinate3 nodes |
| material | information related to Material nodes |
| normal | information related to Normal nodes |
| texcoord | information related to TextureCoordinate2 nodes |
| face | information related to IndexedFaceSet nodes including LOD generation |
| line | information related to IndexedLineSet node including LOD generation |
| join | if the parameter -j is specified, the program tries to join nodes - if this section is specified, information about this process will be printed |
| tree | print out a scheme of the VRML node tree |
| triangulator | information related to the triangulator (used for polygons with more than four vertices) |
| default | equal to coord+material+normal+texcoord+face+line |
| all | all sections (not recommended) |
No Levels of Detail will be generated ! The program only removes double defined coordinates, materials, normals, texture coordinates, faces and lines and eliminates (some) useless nodes with no references.
The program tries to join nodes.
e.g. IndexedFaceSet nodes, Coordinate3 nodes, ...
This is usefull e.g. if an object consists of many many IndexedFaceSets
with only few faces inside. Without joining the LOD-generator can't produce
proper LODs and the objects tend to become holes. On the other side separate
IndexedFaceSet nodes have separate LODs with separate ranges for switching.
(-2 | --errorvolume) weight
(-3 | --weightedmean) weight
The program uses a weighted mean of three algorithms for selecting a representative of some points. With this three parameters you can change the default weights. The errorarea algorithm tries to minimize the change in the surface area of the involved polygons (this is the best algorithm). The errorvolume algorithm ties to minimize the volume which is calculated as the sum of tetraeders (the base areas are the involved faces, the tops are the selected representatives). The weightedmean algorithm simply calculates the deviation to the weighted mean of the points (the weight is the count of points a point is already the representative). For IndexedLineSet nodes always the weightedmean algorithm is used.
(-c | --cameraheightangle) radian
This parameter defines the total vertical angle of the viewing volume (see VRML-specification: PerspectiveCamera). This angle is needed for calculating the ranges of the LODs. Unfortunately in VRML this ranges are not independent from the camera. If this parameter is not specified, the program takes the first perspective camera found in the inputfile. If no camera was found, the default camera is taken (height angle = pi/4).
(-e | --errorrange) percentage
This parameter affects the calculation of the ranges of the LODs for switching. With this parameter you can specifiy the maximum deferral of the points on screen in percent of the height of the viewing window. With a high errorrange value LOD switching is performed at lesser distances but the image quality is lower.
The count of the LODs of an IndexedFaceSet or IndexedLineSet can't be set directly. You can only specify the minimal difference of points between two LODs in percent. This doesn't mean that the difference is exactly equal to this value - the difference can be much higher. e.g. if LOD n uses 100 points, LOD n+1 uses a maximum of 80 points.
Used for extracting a specified LOD. Only LODs with this number will be printed. If this parameter is specified the program doesn't create VRML LOD nodes only the IndexedFaceSet respectively IndexedLineSet node of the specified LOD number will be printed. If a node doesn't have a LOD with this number (not enough LODs) nothing will be printed. LOD 0 is the original data (-x 0 is equivalent to -n ).
While generating LODs faces can collapse into lines. If such a line is equal to an egde of a face or the line is equal to a line already in the set, the line will be eliminated. For each LOD the remainding lines will be witten out into an extra IndexedLineSet node. If this parameter is specified all lines will be eliminated. Note: this parameter has absolutely nothing to do with generating LODs of IndexedLineSet nodes.
Normaly quadrangles will be split into triangles only if they are not convex or too much distorted in 3D (see parameter -s). If this parameter is specified, quadrangles will always be split into two triangles. Polygons with more than four vertices will always be split into triangles independent from this parameter.
(-s | --quadsplitangle) radian
If a quadrangle is too much distorted in 3D it will be split into two triangles (see also parameter -q). A quadrangle will be split if one of the angles between the normals (calculated by the program) of the vertices in opposite side is greater than the quadsplitangle. The action will be performed so that the angle between the two new triangles is minimal. If this parameter is not specified a default value of 0.174533 (10 degree) will be used.
With this option you can set the indention used for (sub)nodes and fields. The default indention is 4.
The program uses optimal fill. This means count spaces will be replaced by a tab. By default 8 spaces will be replaced by one tab. You need this option only if your system respectively editor uses an other definition.
No indention of the output is made. This is not equal to option -I 0 because the values of fields also won't be indented.
(-D | --decimalcountperline) count
With this option you can specify the maximum count of integer values per line in the outputfile. Per default a count of 8 is used.
(-F | --floatcountperline) count
Whit this option you can specifiy the maximum count of floatingpoint values per line. Per default a count of 6 is used.
If a option is not specified the following default values will be used:
| short name | long name | default value |
| -1 | --errorarea | 8 |
| -2 | --errorvolume | 1 |
| -3 | --weightedmean | 0 |
| -c | --cameraheightangle | 0.785398 radian (90 degree) |
| -e | --errorrange | 2 % |
| -m | --mindiff | 20 % |
| -s | --quadsplitangle | 0.174533 radian (10 degree) |
| -I | --indent | 4 |
| -T | --tab | 8 |
| -D | --decimalcountperline | 8 |
| -F | --floatcountperline | 6 |