This software is free but we ask that: 1) Any incorporation of this software or pieces of this software in commercial products are subject to prior written permission of the United States Geological Survey. 2) You let us know of any enhancements you make to the software. Please send comments or further questions to: John Evans | jevans@sakhalin.er.usgs.gov U.S. Geological Survey | (508) 457-2283 | FAX (508) 457-2310 384 Woods Hole Road | http://sakhalin.er.usgs.gov/jevans.html Woods Hole, MA 02543-1598 | "Be seeing you.." AVS Modules avs2vrml(6) NAME avs2vrml - convert and save an avs geometry to a VRML file SUMMARY Name avs2vrml Author John Evans Atlantic Marine Geology United States Geological Survey Type render Input geometry Output *.wrl file Parameters Name Type Default Filename string "fname.wrl" draw_polylines toggle switch false draw_djpolylines toggle switch false draw_ascii toggle switch false DESCRIPTION The avs2vrml module saves an AVS geometry data structure as an equivalent VRML Version 1.0 compliant *.wrl file. Meshes, polyhedrons, spheres, and polytriangles are fully-supported. Labels don't quite work yet. INPUTS Geometry (required; geometry) An AVS geometry, created with the libgeom library or by another AVS module. PARAMETERS Filename The name of the file the converted geometry should be stored. draw_polylines Toggle switch to indicate whether or not polylines should be drawn as part of the polytriangle geometry. Default is false. draw_djpolylines Toggle switch to indicate whether or not disjoint polylines should be drawn as part of the polytriangle geometry. Default is false. draw_ascii Toggle switch to indicate whether or not the AVS label geometry type should be attempted. The text is not positioned very well, so the user would have to edit the *.wrl file until an acceptable orientation is found. Default is false. OUTPUTS - LIMITATIONS, EXAMPLES and EFFICIENCY CONSIDERATIONS The reason for the toggle switches is that some VRML viewers currently don't support IndexedLineSets *with color* very well. The resulting *.wrl file tends to look bad, kind of like crumpled wax paper. As viewers get better, this problem should disappear. The AVS Label geometry has posed certain problems I've not been able to solve yet, as mentioned above, hence the reason for a toggle switch in this case. In this example, a geometry is read by READ GEOM displayed by the Geometry Viewer and converted by avs2vrml. READ GEOM |___________________ | | AVS2VRML GEOMETRY VIEWER AVS does not currently support multiple geometry connections for user-written modules, so a work-around is needed for networks with several geometry-producing modules. This work-around is a utility called "vrmlcat", and is included with this distribution. The use of vrmlcat is demonstrated by the following example. READ GEOM READ GEOM |____________________________________| | | | AVS2VRML GEOMETRY VIEWER AVS2VRML Each avs2vrml module will produce it's own *.wrl file. After the network has run to completion, the user can scoop up all the component *.wrl files into a single master *.wrl file by typing from the command line > vrmlcat -o master.wrl component1.wrl component2.wrl ... or, perhaps easier, > ls *.wrl | vrmlcat -o master.wrl Note that each component.wrl file is by itself a valid VRML file. If you run the network multiple times, be sure to delete your old *.wrl files, otherwise the 2nd invocation method of vrmlcat will suck them into your master.wrl file, increasing its size greatly, and you might not be able to detect it from your VRML viewer except for the fact that rendering will be getting slower and slower and slower... The rendering of *.wrl files containing a large number of spheres tends to be glacially slow. RELATED MODULES read geom, and all modules producing geometry Release 1.0 avs2vrml(6)