06-visualisation.Rmd

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knit: bookdown::preview_chapter
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# Efficient visualisation
  
## Rough outline
  
  * Efficient base graphics
    * Set up par function
    * Custom palettes
  * ggplot2
  * Interactive graphics
    * plotly, shiny, leaflet, htmlwidgets

## Cairo type

These are just some thoughts/observations

When you use `cairo` to save plots, we get anti-aliasing. The standard
graphic devices, `png`,and `jpeg` save graphics as either `c("cairo", "Xlib", "quartz")`.
By default, it goes for `getOption("bitmapType")`. Under a proper OS, such as Linux, 
this will default to `cairo`. Under windows, it seems to go for `NULL`, which results in using
`X11`

For example, compare
```{r eval=FALSE}
set.seed(1)
x = rnorm(100)
png("fig1.png", type="cairo")
plot(x)
dev.off()

png("fig2.png", type="Xlib")
plot(x)
dev.off()
```
 
 * Can you just force `type="cairo"` in Windows - probably not.
 * If you use the `cairo` package under Windows, can you then access `type="cairo"`.
 Or do you need to use the `cairo::` functions.
 * No idea about Macs.
 
Search the web brings up a few out of date pages:

  * http://gforge.se/2013/02/exporting-nice-plots-in-r/