[R] rgl package and animation

[Robert Baer]

-- snip --
  On 11/4/2012 7:45 AM, Duncan Murdoch wrote:
>>>
>>> First, draw the new sphere at the first point and save the object id:
>>>
>>> sphereid <- sphere3d(dat[1,c("X", "Y", "Z")], col="red", radius=1)
>>>
>>> # Also save the spinner that you like:
>>>
>>> spin <- spin3d( ) #maybe with different parms
>>>
>>> # Now, the animation function:
>>>
>>> f <- function(time) {
>>>    par3d(skipRedraw = TRUE) # stops intermediate redraws
>>>    on.exit(par3d(skipRedraw=FALSE)) # redraw at the end
>>>
>>>    rgl.pop(id=sphereid) # delete the old sphere
>>>    pt <- time %% 40 + 1 # compute which one to draw
>>>    pnt <- dat[pt, c("X", "Y", "Z")] # maybe interpolate instead?
>>>    sphereid <<- spheres3d(pnt, radius=1, col="red")
>>>    spin(time)
>>> }
>>>
>>> Duncan Murdoch
>>
>> Thanks so much Duncan!
>>
>> I probably never would have gotten there without your help. (Especially
>> since I had to look at the help for the <<- operator, which is
>> conceptually a level beyond where I usually work).   It would be great
>> to have an additional creative example or two for  f(time) functions in
>> the play3d() help.  Your useful code comments really help me see what
>> needs to happen in an f(time) function.
>>
>> I really appreciate that you took the time to get me going!
>
>
> I've made a small addition to the spin3d function and added an example 
> to the ?spin3d page.  This isn't on CRAN yet, but you can get the 
> latest from R-forge.  Make sure you get 0.92.898 or newer.
>
> The new example shows a rotating view of spinning cubes, using the 
> sprites3d function within the animation function.
>
> Duncan Murdoch
>
Thanks so much for taking the time to do this and for all the other 
contributions you make to the R community!

I should tell you that I also looked at your rgl function writeWebGL() 
over the weekend, and I think it holds tremendous potential for sharing 
visualizations of multidimensional data with a non-technical audience.  
Who knew it could be so easy to move three dimensional data from R to 
the web?

Rob Baer

-- 
__________________
Robert W. Baer, Ph.D.
Professor of Physiology
Kirksille College of Osteopathic Medicine
A. T. Still University of Health Sciences
Kirksville, MO 63501 USA