[R-sig-Geo] Avoid axis labels, ticks and marks in ggRGB() plot

[Benjamin Leutner]

The problem with your first approach is that there is no "data layer" 
which could span the coordinate axes.
Since ggRGB by default uses an annotation_raster() in order to keep your 
"fill" dimension free for other data,  the coordinate limits are empty, 
hence the plotted raster is lost in the dimensionless void and you get 
see nothing ;-)

I would recommend to start your plot with ggRGB like this:

ggRGB(rlogo, r=1, g=2, b=3) +
   theme(
     axis.text = element_blank(),
     axis.ticks = element_blank(),
     axis.title = element_blank())


If you do want to use it with ggLayer = TRUE, there should be at least 
one "geom" with actual data in it (or you'd have to set ggRGB(..., 
geom_raster=TRUE), but I don't see any benefit in that and it would give 
you a huge legend with one entry per rgb color...)

best,
Benjamin

On 03/13/2017 12:10 PM, Agustin Lobo wrote:
> In order to save space, I prefer to avoid coordinates in the plot
> generated by ggRGB. Is there any way? I've tried:
>
> ggplot() +
> ggRGB(rlogo, r=1, g=2, b=3,ggLayer=TRUE) +
>    theme(
>      axis.text = element_blank(),
>      axis.ticks = element_blank(),
>      axis.title = element_blank())
>
> but get an empty plot.
> I can circumvent the problem as follows, but it is kind of ugly and complicated,
> there must be another way:
>
> a <- as(extent(rlogo), 'SpatialPolygons')
> y <- fortify(a,region=id)
> ggplot(data=y,aes(y=lat, x=long)) +
>    ggRGB(rlogo, r=1, g=2, b=3,ggLayer=TRUE) +
>    geom_polygon(colour="yellow", fill=NA) +
>    guides(fill=FALSE) +
>    coord_fixed(ratio=1) +
>    theme(
>      axis.text = element_blank(),
>      axis.ticks = element_blank(),
>      axis.title = element_blank())
>
> Agus
>
> _______________________________________________
> R-sig-Geo mailing list
> R-sig-Geo at r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>

-- 
Benjamin Leutner M.Sc.
PhD candidate

Department of Remote Sensing
University of Wuerzburg
Campus Hubland Nord 86
97074 Wuerzburg, Germany

Tel: +49-(0)931-31 89594
Fax: +49-(0)931-31 89594-0
Email: benjamin.leutner at uni-wuerzburg.de
Web: http://www.fernerkundung.uni-wuerzburg.de