[R-sig-Geo] Triangulation questions

[Sébastien Durand]

Hello,

I have an irregular data set that I which to map using delaunay triangulation, using vector based representation! 
After spending quite a lot of time in the mailing list and in diverse package library, my discovery is that cannot still find a way to accomplish what I am looking for. 

1- Since most packages allow for 2d triangulation, I have been able to actually layout of each triangles of the convex hull, but how to I get to apply the Z value to all of those triangles?

	Personally, I did the average of all the corner of every triangle, apply that average to the triangle polygons and plotted them.
	My reaction, there must be a better way, there must already have a function that would allow me to do this?

2- Moreover, after looking at Delaunay triangulation information on the web, I found that some software are creating sub triangles (inside every triangle) to provide through the means of interpolation more definition to every triangles. 

Using interpolation, they would generate extra sets of polygons inside the actual triangle, thus giving a smoother map...  Any idea if a function like that exist in R.


3- I am very open regarding the mean by which I am gonna plot those data, I would also be very happy to try out a raster solution... 


So I just can't wait to ear back from you guys...

Thanks