The fabricerin (spelled fabrikerine) package allows you to create
easily canvas elements within your Shiny app and RMarkdown documents.
Thanks to Garrick Aden-Buie, you
can also use it within your
xaringan slides. You can use the
canvas to render shapes, images and text. You can also create a canvas
for drawing/taking notes purposes. Under the hoods, fabricerin relies
on the fabricjs JavaScript library.
You can install fabricerin from
CRAN with:
install.packages("fabricerin")You can install the development version from GitHub with:
# install.packages("remotes")
remotes::install_github("feddelegrand7/fabricerin")First of all, I’d like to state that all the example provided apply the
same way to Shiny and Rmd documents. fabricerin is not an R wrapper
for the fabricjs library. The package doesn’t cover all the capabilities
of the library. The fabricerin package relies only on some specified
features that according to me will help Shiny/Rmd users. Of course, if
you need some improvement, feel free to create a Pull Request.
fabric_drawing() is pretty useful when you want to teach something and
write some notes at the same time, below I provide an example using the
xaringan package. Inside a xaringan slide you can just (for example)
run R code in the left and take notes in the right:
Important: When you change a color, make sure that the erase box is not checked.
fabric_drawing() can be used the same way in Shiny:
library(shiny)
library(fabricerin)
ui <- fluidPage(
fabric_drawing(cid = "canvas123")
)
server <- function(input, output){}
shinyApp(ui, server)
Currently, fabricerin supports three types of shapes: Rectangle,
Triangle, Circle and Polygon. The user can interact with the shape and
modify its position, size and rotation. If you want to disable this
interactivity, you can set selectable =FALSE
library(shiny)
library(fabricerin)
ui <- fluidPage(
fabric_shape(cid = "canvaId", # canvas id
cfill = "orange", # canvas color
cwidth = 800, # the width of the canvas
cheight = 600, # the height of the canvas
shapeId = "shapeId", # shape id
shape = "Rect",
fill = "red", # shape color
width = 400,
height = 400,
left = 100, # the position of the shape from the left relative to the canvas
top = 100, # the position of the shape from the top relative to the canvas
strokecolor = "darkblue",
strokewidth = 5,
selectable = TRUE)
)
server <- function(input, output){}
shinyApp(ui, server)
You can add as many shape as you want to an existing canvas using the
fabric_shape_add() function. Don’t forget to reference the
preexisting canvas with its ID:
library(shiny)
library(fabricerin)
ui <- fluidPage(
fabric_shape(cid = "canvaId",
shapeId = "cr1",
shape = "Circle",
radius = 30,
left = 100),
fabric_shape_add(cid = "canvaId",
shapeId = "cr2",
shape = "Circle",
radius = 30,
left = 200),
fabric_shape_add(cid = "canvaId",
shapeId = "cr3",
shape = "Circle",
radius = 30,
left = 300),
fabric_shape_add(cid = "canvaId",
shapeId = "cr4",
shape = "Circle",
radius = 30,
left = 400)
)
server <- function(input, output){}
shinyApp(ui, server)
You can insert an image within a canvas a play with it using the
fabric_image() function. Note that this function accepts only URL
external images.
ui <- fluidPage(
fabric_image(cid = "cimage",
cfill = "lightblue",
imgId = "Rimg",
imgsrc = "https://upload.wikimedia.org/wikipedia/commons/thumb/1/1b/R_logo.svg/724px-R_logo.svg.png")
)
server <- function(input, output) {}
shinyApp(ui = ui, server = server)
Similar to shapes, you can add images to preexisting canvas using the
fabric_image_add() function:
library(shiny)
library(fabricerin)
ui <- fluidPage(
fabric_image(cid = "cimage",
imgId = "Rimg",
imgsrc = "https://upload.wikimedia.org/wikipedia/commons/thumb/1/1b/R_logo.svg/724px-R_logo.svg.png",
imgheight = 200,
imgwidth = 200),
fabric_image_add(cid = "cimage",
imgId = "rstudioimg",
imgsrc = "https://raw.githubusercontent.com/rstudio/hex-stickers/master/PNG/dplyr.png",
imgwidth = 200,
imgheight = 200,
left = 400)
)
server <- function(input, output) {}
shinyApp(ui = ui, server = server)
The fabric_text() function has many arguments, feel free to check them
out:
ui <- fluidPage(
fabric_text(cid = "cId",
textId = "text",
text = " 'But A Hero Is A Guy Who Gives Out The Meat To Everyone Else. \\n I Want To Eat The Damn Meat!' \\n Monkey D. Luffy",
cfill = "#DD5347",
left = 120,
shadowCol = "blue",
fontSize = 20,
fontWeight = "bold",
lineHeight = 3
)
)
server <- function(input, output) {}
shinyApp(ui = ui, server = server)
Here also, we can use the fabric_text_add() function to incorporate a
text object within a canvas element:
library(shiny)
library(fabricerin)
ui <- fluidPage(
fabric_shape(cid = "canvas123",
cfill = "lightblue",
cwidth = 1000,
shapeId = "tri1",
shape = "Triangle",
fill = "darkblue"),
fabric_text_add(cid = "canvas123",
textId = "txt1",
text = "This is a darkblue Triangle !",
left = 350
)
)
server <- function(input, output) {}
shinyApp(ui = ui, server = server)
You can set an image as a background or as a foreground (overlay) for a canvas as follows:
Note that due to security reasons, you won’t be able to replicate the following example on some images’ sources.
ui <- fluidPage(
fabric_shape(cid = "canvas123",
shapeId = "tri1",
shape = "Triangle",
fill = "lightblue"),
fabric_curtail(cid = "canvas123",
imgsrc = "https://st.depositphotos.com/1642482/1904/i/950/depositphotos_19049237-stock-photo-leaf.jpg",
type = "background"
)
)
server <- function(input, output) {}
shinyApp(ui = ui, server = server)
Please note that the fabricerin project is released with a Contributor Code of Conduct. By contributing to this project, you agree to abide by its terms.