Hi,

I am trying to install the package for DECORANA onto R, I have tried the CCA
and it does not seem to work. Does anyone know?
Tawanda

On Fri, Nov 13, 2009 at 9:53 AM, kvarpun <jallouli.med.amine@gmail.com>wrote:

>
>
> Duncan Murdoch-2 wrote:
> >
> > On 11/12/2009 11:37 AM, kvarpun wrote:
> >>
> >> Duncan Murdoch-2 wrote:
> >>>
> >>> On 11/12/2009 4:56 AM, kvarpun wrote:
> >>>> Hi,
> >>>>
> >>>> Is there an R package that reads and writes 3D images having the
> >>>> extension
> >>>> PLY (PLY images of Stanford University)?
> >>>>
> >>>> Currently, I installed the package misc3d. This package displays these
> >>>> images PLY, but it can neither read nor write PLY images.
> >>>
> >>> This doesn't make sense.  How can it display PLY images if it can't
> read
> >>> them?  Could you give an example?
> >>>
> >>> Duncan Murdoch
> >>>
> >>>>
> >>>> Thank you to tell me the name of a package that will read and write
> >>>> such
> >>>> images.
> >>>
> >>> ______________________________________________
> >>> R-help@r-project.org mailing list
> >>> https://stat.ethz.ch/mailman/listinfo/r-help
> >>> PLEASE do read the posting guide
> >>> http://www.R-project.org/posting-guide.html
> >>> and provide commented, minimal, self-contained, reproducible code.
> >>>
> >>>
> >>
> >> Thank you for quick answer.
> >> I have to inform you that the only available functions in the package
> >> misc3d
> >> are:
> >>
> >> contour3d                 Draw an Isosurface, a Three Dimension Contour
> >> Plot
> >>   drawScene            Rendering of Triangular Mesh Surface Data
> >>   image3d                Draw Points on a 3D Grid
> >>   kde3d                    Compute a Three Dimension Kernel Density
> >> Estimate
> >>   makeTriangles       Triangle Mesh Functions
> >>   parametric3d          Draw a 3D Parametric Plot
> >>   perspLighting          Lighting Functions
> >>   phongLighting         Lighting Functions
> >>   pointsTetrahedra     Create a Set of Tetrahetra Centered at Data
> Points
> >>   scaleTriangles       Triangle Mesh Functions
> >>   slices3d                 Interactive Image Slices of 3D or 4D Volume
> >> Data
> >>   surfaceTriangles     Create a Triangle Mesh Representing a Surface
> >>   teapot                    Utah Teapot
> >>   translateTriangles   Triangle Mesh Functions
> >>   updateTriangles      Triangle Mesh Functions
> >>
> >> None of them does read/write a PLY file.
> >>
> >>
> >> You will find below a simple code for drawing a 3D image. The displayed
> >> image is stored in the package misc3d (not read from a file).
> >>
> >> library(misc3d)
> >> data(teapot)
> >>
> >> haveRGL <- suppressWarnings(require(rgl,quietly=TRUE))
> >> ttri <- makeTriangles(teapot$vertices, teapot$edges, color = "red",
> >> color2 =
> >> "green")
> >>
> >> ## draw the teapot
> >> drawScene(ttri,screen=list(y=-30,x=40), scale = FALSE)
> >>
> >> str(teapot)
> >> # > str(teapot)
> >> # List of 2
> >> # $ vertices: num [1:3, 1:1976] -3,00 1,65 0,00 -2,99 1,65 ...
> >> # $ edges   : int [1:3, 1:3751] 1455 1469 1459 1449 1455 1459 1462 1449
> >> 1459
> >> 1469 ...
> >>
> >> # My images (PLY images) have vertices and edges like the teapot image
> in
> >> the example. If PLY images are read by R, I will be able to manipulate
> >> them.
> >
> > Okay, I understand now.  Yes, R can display 3D images based on lines and
> > polygons using the rgl package or scatterplot3d or grid graphics, but
> > those have nothing to do with PLY files.  As far as I know there is no
> > existing code to read or write a PLY file, but from the look of it, it's
> > a simple format and it wouldn't be hard to write input/output routines.
> >   The likely problems are:
> >
> >   - it's an open ended format, with each application allowed to define
> > its own record types.  If your files come from an application that did
> > that you may have trouble working out what was intended and reading it
> in.
> >
> >   - some of the recommended elements are not supported in rgl or other
> > 3D renderers in R.  In particular, polygons with more than 4 vertices
> > need to be decomposed into triangles or quads, and rgl knows nothing
> > about refraction index:  you'd probably need a ray-tracing renderer for
> > that.
> >
> >   - rgl scenes contain text, and as far as I can see, there's no way to
> > include that in a standard PLY file, so you'd need to invent your own
> > record type for it.  Text is always hard to describe graphically, so
> > this wouldn't be easy.
> >
> > Duncan Murdoch
> >
> > ______________________________________________
> > R-help@r-project.org mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide
> > http://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.
> >
> >
> Thank you for all these precisions.
> I guess developping an R package for reading/writing PLY files is required.
> Have a nice day.
>
> --
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> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

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