Sam Bryfczynski wrote: > Hello, > I like how compact the jvxl format is and would like to use it in my > own software. However, I am having a bit of trouble wrapping my head > around how to uncompress it. I've read over the JVXL file pdf which > describes the format but am left scratching my head a bit. I am > mainly confused about what the surface voxel bitmap data is. It says > you can use it to find the "critical edges" but I don't know how. > When the document says "We simply list the number of voxels found > sequentially on each side: 115922 outside, 2 inside, 6333 outside, 4 > inside…" what does "on each side" mean? The bottom line is I am trying > to just get the polygons needed to render the isosurface from the jvxl > data. Ive been looking at the source code and the JvxlReader class > and trying to figure out how to best approach this. Any suggestions? > Thanks, >
In a previous message, I wrote the wrong link to the Sage implementation of a JVXL interpreter, because we don't have it in Sage yet. An early version of it is here: http://trac.sagemath.org/sage_trac/attachment/ticket/5249/implicit-surface.patch (search for jvxl to see various classes). Another way to think about JVXL is that it is the run-length encoding of a string 0 0 0 0 1 1 1 1 1 0 0 (0 means you are on one side of the surface, 1 means you are on the other side, each number represents a position in your 3d traversal of space) which encodes down to 4 5 2 Unlike usual run-length encoding, you don't have to specify the value since you know that the values alternate between 0 and 1. So you only need to encode the number of steps you take before crossing the surface again. Thanks, Jason -- Jason Grout ------------------------------------------------------------------------------ Enter the BlackBerry Developer Challenge This is your chance to win up to $100,000 in prizes! For a limited time, vendors submitting new applications to BlackBerry App World(TM) will have the opportunity to enter the BlackBerry Developer Challenge. See full prize details at: http://p.sf.net/sfu/Challenge _______________________________________________ Jmol-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/jmol-users
