Quick Start

This section shows how to get started using Chartreuse. Refer to other sections for more details on how the library works.

Using Chartreuse

To use Chartreuse in your project, add the following to your build.sbt:

libraryDependencies += "org.creativescala" %% "chartreuse" % "0.1-cefd1cf-SNAPSHOT"

Then, in your code, import the library.

import chartreuse.{*, given}

Creating Data

You need some data to create a visualization. You presumably have some real data but for this demonstration we'll create some simple fake data.

import doodle.core.Point
import scala.util.Random

val data =
  List.fill(100)(Point(Random.nextGaussian(), Random.nextGaussian()))

Chartreuse can work with just about any collection class, so it probably doesn't matter how you've stored your data.

Creating a Plot

Now we have data we can create a plot. The simplest way to create a plot is to start with the Layout, which determines how the data will be drawn in the visualization. We'll create a simple scatter plot from our data. This uses the Scatter layout.

import chartreuse.layout.Scatter

val layout = Scatter.default[Point]

We need to add our data to the a Layout to create a Plot that we can draw. Once we have a Plot we can set the title and other properties.

val plot = layout
  .withPlotTitle("Our Amazing Plot")

We can convert a Plot to a Doodle Picture using the draw method, to which we pass the size of the output.

val picture = plot.draw(640, 480)

Then we can render the picture in the usual way for Doodle, which depends on the backend in use. On the JVM we just call the draw method. On the JS backend we call drawWithFrame passing in the id of the DOM element (a String) where we should draw it.

Here are complete examples. Firstly for the JVM.

import cats.effect.unsafe.implicits.global
import doodle.java2d.*
import doodle.syntax.all.*


Now for SVG output in the browser.

import cats.effect.unsafe.implicits.global
import doodle.svg.*
import doodle.syntax.all.*


This will produce output like that shown below.