saveHTML: Insert animations into an HTML page

Description

This function first records all the plots in the R expression as bitmap images, then inserts them into an HTML page and finally creates the animation using the SciAnimator library.

Usage

saveHTML(expr, img.name = "Rplot", global.opts = "", single.opts = "",  navigator = ani.options("nmax") <= 100="" &&="" ani.options("interval")="">=  0.05, htmlfile = "index.html", ...)

Arguments

expr

an R expression to be evaluated to create a sequence of images

img.name

the filename of the images (the real output will be like ‘img.name1.png’, ‘img.name2.png’, ...); this name has to be different for different animations, since it will be used as the identifiers for each animation; make it as unique as possible; meanwhile, the following characters in img.name will be replaced by _ to make it a legal jQuery string:

!"#$%&'()*+,./:;?@[\]^`{|}~

global.opts

a string: the global options of the animation; e.g. we can specify the default theme to be blue using $.fn.scianimator.defaults.theme = 'blue'; note these options must be legal JavaScript expressions (ended by ';')

single.opts

the options for each single animation (if there are multiple ones in one HTML page), e.g. to use the dark theme and text labels for buttons:

'utf8': false, 'theme': 'dark'

or to remove the navigator panel (the navigator can affect the smoothness of the animation when the playing speed is extremely fast (e.g. interval less than 0.05 seconds)):

'controls': ['first', 'previous', 'play', 'next', 'last', 'loop', 'speed']

see the reference for a complete list of available options

navigator

whether to show the navigator (like a progress bar); by default, the navigator is not shown for performance reasons when the number of images is greater than 100 or the time interval is smaller than 0.05

htmlfile

the filename of the HTML file

...

other arguments to be passed to ani.options to animation options such as the time interval between image frames

Value

The path of the HTML output.

Details

It mainly uses the SciAnimator library, which is based on jQuery. It has a neat interface (both technically and visually) and is much easier to use or extend. Moreover, this function allows multiple animations in a single HTML page -- just use the same HTML filename.

Optionally the source code and some session information can be added below the animations for the sake of reproducibility (specified by the option ani.options('verbose') -- if TRUE, the description, loaded packages, the code to produce the animation, as well as a part of sessionInfo() will be written in the bottom of the animation; the R code will be highlighted using the SyntaxHighlighter library for better reading experience).

References

https://github.com/brentertz/scianimator

Examples

Run this code

## A quick and dirty demo
des = c("This is a silly example.\n\n", "You can describe it in more detail.", 
    "For example, bla bla...")
saveHTML({
    par(mar = c(4, 4, 0.5, 0.5))
    for (i in 1:20) {
        plot(runif(20), ylim = c(0, 1))
        ani.pause()
    }
}, img.name = "unif_plot", imgdir = "unif_dir", htmlfile = "random.html", 
    autobrowse = FALSE, title = "Demo of 20 uniform random numbers", 
    description = des)



## we can merge another animation into the former page as long as
## 'htmlfile' is the same; this time I don't want the animation
## to autoplay, and will use text labels for the buttons (instead
## of UTF-8 symbols)
des = c("When you write a long long long long description, R will try to wrap the", 
    "words automatically.", "Oh, really?!")
saveHTML({
    par(mar = c(4, 4, 0.5, 0.5))
    ani.options(interval = 0.5)
    for (i in 1:10) {
        plot(rnorm(50), ylim = c(-3, 3))
        ani.pause()
    }
}, img.name = "norm_plot", single.opts = "utf8: false", autoplay = FALSE, 
    interval = 0.5, imgdir = "norm_dir", htmlfile = "random.html", 
    ani.height = 400, ani.width = 600, title = "Demo of 50 Normal random numbers", 
    description = des)



## use the function brownian.motion() in this package; this page
## is created in 'index.html' under the current working directory
des = c("Random walk of 10 points on the 2D plane:", "for each point (x, y),", 
    "x = x + rnorm(1) and y = y + rnorm(1).")
saveHTML({
    par(mar = c(3, 3, 1, 0.5), mgp = c(2, 0.5, 0), tcl = -0.3, cex.axis = 0.8, 
        cex.lab = 0.8, cex.main = 1)
    ani.options(interval = 0.05, nmax = ifelse(interactive(), 150, 
        2))
    brownian.motion(pch = 21, cex = 5, col = "red", bg = "yellow")
}, img.name = "brownian_motion_a", htmlfile = "index.html", description = des)



## remove the 'navigator' (progress bar)
saveHTML({
    par(mar = c(3, 3, 1, 0.5), mgp = c(2, 0.5, 0), tcl = -0.3, cex.axis = 0.8, 
        cex.lab = 0.8, cex.main = 1)
    ani.options(interval = 0.05, nmax = ifelse(interactive(), 150, 
        2))
    brownian.motion(pch = 21, cex = 5, col = "red", bg = "yellow")
}, img.name = "brownian_motion_b", htmlfile = "index.html", navigator = FALSE, 
    description = c("Random walk of 10 points on the 2D plane", 
        "(without the navigation panel)"))


## use Rweb to create animations
if (interactive()) browseURL(system.file("misc", "Rweb", "demo.html", 
    package = "animation"))

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