In baptiste/minixcali: Excalidraw Document Builder

library(minixcali)
library(purrr)
library(knitr)
opts_chunk$set(message = FALSE, 
               warning=FALSE,
               fig.width = 7,
               fig.height = 4, 
               out.width='50%')

Let's add a flametree into Excalidraw.

The R object

The flametree package uses ggplot2 for drawing, so we can piggyback the aesthetic mapping and simply extract point coordinates and colours in the plot's data.

library(minixcali)
library(flametree)
library(ggplot2)

dat <- flametree_grow(seed = 4, time = 5) # data structure
img <- flametree_plot(data = dat) # ggplot object
img

gb <- ggplot_build(img)

tr <- gb$data[[1]]
b <- split(tr, tr$group)
str(b, list.len = 3)

From there it's a relatively straight-forward process to add one branch at a time to the Excalidraw tree.

d <- Excali_doc()


library(scales)

scale <- 100

for (ii in seq_along(b)) {
  s <- b[[ii]]

  r_x <- range(s$x)
  r_y <- range(s$y)

  m <- scale * cbind(s$x - r_x[1],-s$y - r_y[1])

  shape <- xkd_draw(
    x = scale * r_x[1],
    y =  scale * r_y[1],
    width = scale * diff(r_x),
    height = scale * diff(r_y),
    strokeWidth = 1,
    roughness = 0L,
    strokeSharpness = "round",
    groupIds = list("levelplot", paste0('level-', ii)),
    fillStyle = "solid",
    strokeColor = s$colour[1],
    backgroundColor = s$colour[1],
    points = m)

  d$add(shape)

}

d$export('tree.json')