Software Engineer
Published
Edited
May 21, 2021
md`# Place random rectangle in a box`
svg = {
const rectangles = generateRectangles();
const svg = d3.create("svg").attr("viewBox", [0, 0, 400, 200]);
const g = svg.append("g");
g.selectAll("rect")
.data(rectangles)
.join("rect")
.attr("x", d => d.p1.x + 20)
.attr("y", d => d.p1.y + 0.5)
.attr('width', d => d.p2.x - d.p1.x - 1)
.attr('height', d => d.p2.y - d.p1.y - 1)
.style('fill', (d, i) => getRandomColor());
svg.call(
d3
.zoom()
.extent([[0, 0], [400, 200]])
.scaleExtent([1, 10])
.on("zoom", zoomed)
);
function zoomed({ transform }) {
g.attr("transform", transform);
}
return svg.node();
}
function getRandomColor() {
var color = '#';
for (var i = 0; i < 6; i++) {
color += (Math.random() * 16 | 0).toString(16);
}
return color;
}
function Point(x, y) {
this.x = x;
this.y = y;
}
function Rectangle(p1, p2) {
this.p1 = p1;
this.p2 = p2;
}
(Rectangle.prototype.isInside = function(r) {
function check(a, b) {
return (
(a.p1.x <= b.p1.x &&
b.p1.x <= a.p2.x &&
a.p1.y <= b.p1.y &&
b.p1.y <= a.p2.y) ||
(a.p1.x <= b.p2.x &&
b.p2.x <= a.p2.x &&
a.p1.y <= b.p2.y &&
b.p2.y <= a.p2.y) ||
(a.p1.x <= b.p2.x &&
b.p2.x <= a.p2.x &&
a.p1.y <= b.p1.y &&
b.p1.y <= a.p2.y) ||
(a.p1.x <= b.p1.x &&
b.p1.x <= a.p2.x &&
a.p1.y <= b.p2.y &&
b.p2.y <= a.p2.y)
);
}
return check(this, r) || check(r, this);
})
function generateRectangles() {
function p() {
return (Math.random() * 100) | 0;
}
function s() {
return (25 + Math.random() * 50) | 0;
}
var rectangles = [],
r,
size,
x,
y,
isInside,
i,
counter = 0;
for (i = 0; i < 20; i++) {
counter = 0;
do {
counter++;
x = p();
y = p();
size = s();
r = new Rectangle(new Point(x, y), new Point(x + size, y + size));
isInside = rectangles.some(function(a) {
return a.isInside(r);
});
} while (isInside && counter < 1000);
counter < 1000 && rectangles.push(r);
}
return rectangles;
}
d3 = require("d3@6")
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