Legend

[schloerke]

Solves: #29

• extract and make file of legend. also sent to display_obj.jsonp.
• split to files vs. single file is a facet_trelliscope flag. also sent to display_obj.jsonp.
• make "title: subtitle" the default description
• if axis is right or top, yell at them

Also pulls in PR #27 (which in turn does #26 and #20). Merging this PR would auto merge the other three PRs

[schloerke]

library(ggplot2)
mpg2 <- mpg
mpg2$drv <- as.factor(mpg2$drv)
mpg2$cyl <- as.factor(mpg2$cyl)

load_all(); qplot(displ, hwy, data = mpg2) + facet_trelliscope(~ year, ncol = 2, nrow = 1, scales = "sliced", path = "_ignore/simple_split")
load_all(); qplot(displ, hwy, data = mpg2, color = year) + facet_trelliscope(~ year, ncol = 2, nrow = 1, scales = "sliced", path = "_ignore/simple_split_color")
load_all(); qplot(displ, hwy, data = mpg2) + facet_trelliscope(~ year, ncol = 2, nrow = 1, scales = "sliced", split_layout = FALSE, path = "_ignore/simple_whole")
load_all(); qplot(displ, hwy, data = mpg2, color = year) + facet_trelliscope(~ year, ncol = 2, nrow = 1, scales = "sliced", split_layout = FALSE, path = "_ignore/simple_whole_color")

[hafen]

Thanks for all this! The scales aspect works great!

I merged this PR and made some edits and put it here: https://github.com/hafen/trelliscopejs/tree/schloerke-legend.

What I did:

• split_layout and has_legend are now written to displayObj.json (instead of the global config.json as it was before). This allows it to vary per-display instead of being a global setting.
• When split_layout is TRUE, additional info about the aspect ratio for the left and bottom axes is stored in displayObj.json because the viewer will need to know this.
• Because of the above, I broke out the width/height calculation stuff in make_png() so that I can calculate the final width and height of the axes without calling make_png().
• I set split_layout to FALSE by default and added an error if it is set to TRUE for now because the viewer can't support it yet. This will take some work on the viewer side of things.

Something to think about: When either axis is set to "free" or "sliced", we know the axis will vary per panel so we might as well leave the axes in the plot. Only in the case of an axis being "same" we could just store a single instance of the axis (instead of writing out an axis per panel). That would result in a lot fewer files and calls to make_png() and would simplify things on the viewer's end. We can discuss this more later.