S2PLOT:S2web

From S2PLOT

s2web: Embedding S2PLOT Content in Web Pages (using Flash)

Since version 2.02, S2PLOT has been able to write the displayed geometry to a VRML 97 format file. This format was selected as it can be read in by Adobe Acrobat 3D and embedded in Portable Document Format (PDF) files. See the section on 3-d PDF for more information.

We also use the VRML export capability of S2PLOT to produce content for the freely available S2PLOT Flash player, s2web. A syntax-only translation using the | NIST-provided v2x3d yields an X3D file from the S2PLOT-exported VRML, and the 3-d scene in the X3D file can be read and displayed by s2web. Camera control and interaction with the scene in the s2web application is almost identical to that in a native S2PLOT program. Volume rendering, billboards, handles and frame-based animation are all supported.

The s2web functionality of S2PLOT is documented in the following paper. If you use s2web to embed S2PLOT content in a web page, please cite or acknowledge this source:

• Fluke, C.J., Barnes, D.G., Jones, N.T., 2008, "Interchanging Interactive 3-d graphics for Cosmology", submitted to PASA, Oct 2008

Requirements

• S2PLOT version 2.02 or higher
  • version 2.4 or higher recommended
  • S2PLOT is freely available for non-commercial and educational use
• s2web version 0.1 or higher
  • s2web is freely available for non-commercial and educational use
• The VRML97 to X3D converter from the National Institutde of Standards and Technology
  • v2x3d is freely available

VRML export from S2PLOT

Most S2PLOT geometry can be written to VRML format. While running an S2PLOT program, simply press Shift-W and a file called "test.wrl" will be written. It will overwrite any pre-existing "test.wrl" file in the current working directory.

When writing an S2PLOT program whose output may be captured to VRML, keep the following points in mind:

• screen-coordinate geometry is not saved to VRML
• line thickness is not properly supported in VRML
• textured spheres are not presently written to VRML (next version of S2PLOT)
• transparent dots are not presently written to VRML (next version of S2PLOT)
• disks are not presently written to VRML (next version of S2PLOT)
• both static and dynamic S2PLOT geometry is saved to the VRML file
• you can organise parts of your geometry into named sections of the VRML file (model tree) by using the S2PLOT function pushVRMLname
• correct volume rendering requires special attention (see below)
• frame animation is possible (see below)
• billboards can be used but require special attention (see below)
• handles are written and can be used for particular types of interaction (see below)
• Acrobat Reader generally struggles with more than say 5000 pieces of geometry (whether points, lines or facets)
• you can programmatically export the VRML file by declaring the function "void writeVRML20(void)" and calling it from a dynamic S2PLOT callback function