[R-sig-Geo] drawing order in spplot and Line width in sp maps

[Edzer J. Pebesma]

Duncan Golicher wrote:
> Great. Thanks so much. It was obvious really.
> You also seem to have come up with one solution to the line width 
> question asked a couple of days ago,  as this works.
>
> spplot(chisgrid, "dem", panel = function(x,y, ...){
>     panel.gridplot(x,y,...)
>     sp.polygons(municipios, col=1,fill=0,lwd=3,lty=2)
>     })
>
>
>   
Yes, or:

spplot(chisgrid, "dem", sp.layout=list("sp.polygons", municipios, col=1, 
fill=0, lwd=3, lty=2, first=F))

> Duncan
>
> Arien Lam wrote:
>
>   
>> Duncan,
>>
>> After a few tries I found:
>>
>> spplot(chisgrid, "dem", panel = function(x,y, ...){
>>    panel.gridplot(x,y, ...)
>>    sp.polygons(municipios, col=1,fill=0)
>>    })
>>
>> , which is just the reverse nesting order from my previous shot at it.
>> HTH, Arien
>>
>> To be precise, this worked on:
>>  
>>
>>     
>>> sessionInfo()
>>>    
>>>
>>>       
>> Version 2.3.1 (2006-06-01)
>> i486-pc-linux-gnu
>>
>> attached base packages:
>> [1] "methods"   "stats"     "graphics"  "grDevices" "utils"     "datasets"
>> [7] "base"
>>
>> other attached packages:
>> lattice       sp
>> "0.13-8" "0.8-16"
>>
>>
>> This approach is advocated for tweaking trellis plots.
>>
>> On Thu, July 6, 2006 17:52, Duncan Golicher wrote:
>>  
>>
>>     
>>> Thanks for this Arien,
>>>
>>> Just can't get it to work though. I messed around a bit more yesterday
>>> but couldn't find a way. No one else on the list replied. I have another
>>> reason to want to do something similar, so I was hoping there was a work
>>> around out there. Here is the data if you (or anyone else) can help.
>>>
>>> load(file=url("ftp://200.23.34.16/simulacion/SPATIAL/chisgrid.rob"))
>>> load(file=url("ftp://200.23.34.16/simulacion/SPATIAL//municipios.rob"))
>>>
>>> #municipios was originally imported from a shapefile. The "dem" is a
>>> coarse 1 km x 1km grid imported from GRASS 5.7. Both use UTM NAD27, but
>>> the projections are not #set. The data represents the state of Chiapas
>>> in Southern Mexico
>>>
>>> image(chisgrid,"dem",col=terrain.colors(100))
>>> plot(municipios,add=T)
>>>
>>> #Gives what we wanted in base graphics
>>>
>>> #But
>>>
>>> spplot(municipios, "AREA", panel <- function(x,y,...){
>>>    sp.grid(chisgrid)
>>>    panel.polygonsplot(x,y,...)
>>>    })
>>> #Doesn't
>>>
>>> #and
>>>
>>> municips <- list("sp.polygons", municipios)
>>> spplot(chisgrid["dem"],sp.layout=municips)
>>>
>>> #Draws them in the wrong order.
>>>
>>> #As an aside, this is great fun with rgl and the students loved it. Can
>>> anyone improve the code?
>>>
>>> view3d<-function(grid=chisgrid,dem=1,drape=2,exag=3,pal=sp.theme()$regions$col){
>>>  fullgrid(grid)<-TRUE
>>>  y<-grid[[dem]]*exag
>>>  y[is.na(y)]<-0
>>>  dim(y)<-grid at grid@cells.dim
>>>
>>>  x <- grid at grid@cellsize[1]*(1:grid at grid@cells.dim[1])
>>>  z <-grid at grid@cellsize[2]*(1:grid at grid@cells.dim[2])
>>>
>>>  y2<-grid[[drape]]
>>>  y2[!is.na(y2)]<-as.numeric(cut( y2[!is.na(y2)],length(pal)))
>>>  y2[is.na(y2)]<-0
>>>
>>>  ylim <- range(y2)
>>>  ylen <- ylim[2] - ylim[1] + 1
>>>
>>>  pal<-c("black",pal)
>>>  col <- pal[ y2-ylim[1]+1 ] # assign colors to heights for each point
>>>
>>>  rgl.clear()
>>>  rgl.surface(x, z, y, color=col)
>>> }
>>>
>>> view3d(drape=1,pal=terrain.colors(100))
>>>
>>> Duncan
>>>
>>>
>>>
>>> Arien Lam wrote:
>>>
>>>    
>>>
>>>       
>>>> I stumbled there too.
>>>> A way is to customize the default panel function within spplot.
>>>>
>>>> Try:
>>>>
>>>> spplot(municipios, "yourvariable", panel <- function(x,y,...){
>>>>    sp.grid(chisgrid)
>>>>    panel.polygonsplot(x,y,...)
>>>>    })
>>>>
>>>> Regards, Arien
>>>>
>>>> Duncan Golicher schreef:
>>>>
>>>>      
>>>>
>>>>         
>>>>> Many thanks to everyone involved in putting together the excelent sp
>>>>> package. I have just used for teaching a brief intro to applied
>>>>> geostats with gstat. Students found life much easier than a year ago
>>>>> when I had to try to explain a less structured approach to the data.
>>>>> A simple question arose after the class. According to the spplot
>>>>> documentation "for grids and polygons sp.layout is drawn afterwards
>>>>> (so the item will not be overdrawn by the grid and/or polygon)".
>>>>> So in this example we expected a DEM to be drawn first, then
>>>>> municipal boundaries.
>>>>>
>>>>>           
>>>>>> class(municipios)
>>>>>>             
>>>>> [1] "SpatialPolygonsDataFrame"
>>>>>           
>>>>>> class(chisgrid)
>>>>>>             
>>>>> [1] "SpatialPixelsDataFrame"
>>>>>
>>>>> municips <- list("sp.polygons", municipios)
>>>>> spplot(chisgrid["dem"],sp.layout=municips)
>>>>>
>>>>> The municipal boundaries are drawn first then overdrawn by the DEM,
>>>>> which was not what we expected or wanted. I couldn't find how to
>>>>> avoid this, apart from the simple solution of ..
>>>>>
>>>>> image(chisgrid,col=terrain.colors(20))
>>>>> plot(municipios,add=T)
>>>>>
>>>>> instead of spplot.The figures on  http://r-spatial.sourceforge.net
>>>>> all appear to have the grid drawn first. Is there a way to reverse
>>>>> this?
>>>>>
>>>>> Duncan
>>>>>
>>>>>        
>>>>>
>>>>>           
>>> --
>>> Dr Duncan Golicher
>>> Ecologia y Sistematica Terrestre
>>> Conservación de la Biodiversidad
>>> El Colegio de la Frontera Sur
>>> San Cristobal de Las Casas,
>>> Chiapas, Mexico
>>>
>>> Email: dgoliche at sclc.ecosur.mx
>>>
>>> Tel: 967 674 9000 ext 1310
>>> Fax: 967 678 2322
>>> Celular: 044 9671041021
>>>
>>> United Kingdom Skypein; 020 7870 6251
>>> Skype name: duncangolicher
>>> Download Skype from http://www.skype.com
>>>
>>>
>>>
>>>    
>>>
>>>       
>>  
>>
>>     
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