Canvas tutorial - Turn SVG scatterplot into Canvas - Extreme level

This scatterplot is made with d3.js and SVG - For the canvas tutorial it is now your job to turn this scatterplot into one uses canvas for the visual part (the drawing of the circles). You can still use d3's helper functions for things such as scales, d3.select, etc.

For the medium level you need to keep the SVG in as well (and thus position both the SVG and canvas (absolutely) on top of each other) and use the SVG for all the textual parts: the axes and titles

For the extreme level, there are 3 steps (getting more difficult with each new step):

level 1 | On a hover, instantaneously change the color of the hovered circle black (and back to the original color when moving out of the circle)
level 2 | On a hover, linearly increase the hovered circle’s size to 1.5 times its original radius and opacity of 1 in 1000ms (and back again to normal size on a mouseout)
level 3 | The same as level 2, but use an easing function for the radius animation

See the other two levels here: Normal level and Medium level

If you're completely stuck (and please, for your own benefit, only then) you can look at the solution for level 1 here

Built with blockbuilder.org

forked from nbremer's block: Canvas tutorial - Turn SVG scatterplot into Canvas - Extreme level

<!DOCTYPE html>

.chart-title {
            font-size: 16px;
            text-anchor: middle;
            letter-spacing: 1.3px;
        }

.axis .title {
            font-size: 12px;
            font-weight: 500;
            text-anchor: middle;
            text-transform: uppercase;
            letter-spacing: 1.3px;
            fill: #6b6b6b;
        }

.axis text {
            font-family: 'Roboto', sans-serif;
            font-size: 11px;
            fill: #919191;
        }

.axis path {
            display: none;
        }

.axis line {
            stroke: #a5a5a5;
        }
    </style>
    
    <link href="https://fonts.googleapis.com/css?family=Roboto:400,500" rel="stylesheet">

<body>
    <script>
        ////////////// Create the SVG //////////////

//****** Add a canvas and position both absolutely to overlap (medium level) *********//
        let margin = {
            top: 40,
            right: 10,
            bottom: 60,
            left: 100
        }
        let width = 1000 - margin.left - margin.right,
            height = 800 - margin.top - margin.bottom

//Create the SVG container
        let svg = d3.select("body")
            .append("svg")
            .attr("width", width + margin.left + margin.right)
            .attr("height", height + margin.top + margin.bottom)
            .append("g")
            .attr("transform", "translate(" + margin.left + "," + margin.top + ")")

////////////// Create scales //////////////

//****** Keep all of these scales as-is ******//

const x_scale = d3.scaleLinear() //rating
            .range([0, width])

const y_scale = d3.scaleLog() //budget
            .domain([500, 500e6]) //in dollars
            .range([height, 0])

const r_scale = d3.scaleSqrt() //profit ratio = revenue / budget
            .domain([0, 6])
            .range([0, 10])

//Make the movies that have the highest profit ratio less visible
        //to balance their increased size
        const opacity_scale = d3.scaleLinear() //profit ratio = revenue / budget
            .domain([0, 100])
            .range([0.2, 0.01])
            .clamp(true)

//A linear color scale to give an idea about when a movie was made
        const color_scale = d3.scaleSequential(d3.interpolateViridis) //release year

////////////// Read in the data //////////////

//Data based on dataset from 
        //https://data.world/popculture/imdb-5000-movie-dataset
        d3.csv("imdb-movies.csv", function (error, data) {
            if (error) throw error

////////////// Final data prep //////////////

//****** Keep as-is ******//

//Make the number columns actually numeric
            data.forEach(d => {
                d.release_year = +d.release_year
                d.budget = +d.budget
                d.revenue = +d.revenue
                d.rating = +d.rating
                d.num_voted_users = +d.num_voted_users
                d.profit_ratio = +d.profit_ratio
            })

////////////// Adjust scales //////////////

//****** Keep as-is ******//

//Set the range for the scales now that the data is read in
            x_scale.domain(d3.extent(data, d => d.rating)).nice()
            color_scale.domain(d3.extent(data, d => d.release_year))

////////////// Create circles //////////////

//*** Replace this section with a loop that goes over all ***// 
            //*** the data and creates a canvas circle for each movie ***//
            //*** using the correct x, y, radius, color and opacity for each ***//

let circle_group = svg.append("g").attr("class", "circle-group")

let circles = circle_group.selectAll(".movie")
                .data(data)
                .enter().append("circle")
                .attr("class", "movie")
                .attr("cx", d => x_scale(d.rating))
                .attr("cy", d => y_scale(d.budget))
                .attr("r", d => r_scale(d.profit_ratio))
                .style("fill", d => color_scale(d.release_year))
                .style("opacity", d => opacity_scale(d.profit_ratio))

////////////// Create axes //////////////

//****** Keep as-is ******//

let x_axis = svg.append("g") //x scale - rating
                .attr("class", "axis x")
                .attr("transform", "translate(0 " + height + ")")
                .call(d3.axisBottom(x_scale))

let y_axis = svg.append("g") //y scale - budget
                .attr("class", "axis y")
                .call(d3.axisLeft(y_scale)
                    .ticks(5)
                    .tickFormat(d3.format("$,.0s"))
                )

////////////// Create titles //////////////

//****** Keep as-is ******//

//Add chart title
            svg.append("text")
                .attr("class", "chart-title")
                .attr("x", width / 2)
                .attr("y", -10)
                .text("comparing budgets versus ratings for nearly 5000 movies across the last 90 years")

//Add x title
            x_axis.append("text")
                .attr("class", "title")
                .attr("x", width / 2)
                .attr("y", 40)
                .text("Rating")

//Add y title
            y_axis.append("text")
                .attr("class", "title")
                .attr("x", 0)
                .attr("y", 50)
                .text("Budget")

////////////// Create hover interaction //////////////

//****** Turn this into a canvas interaction and animation ******//

circles
                .on("mouseover", function(d) {
                    console.log(d.title)
                    d3.select(this)
                        .transition().duration(1000)
                        .attr("r", r_scale(d.profit_ratio) * 1.5)
                        .style("opacity", 1)
                })
                .on("mouseout", function(d) {
                    d3.select(this)
                        .transition().duration(300)
                        .attr("r", r_scale(d.profit_ratio))
                        .style("opacity", opacity_scale(d.profit_ratio))
                })

})//d3.csv

</script>
</body>

https://d3js.org/d3.v4.min.js