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CMYK halftone printing
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<!DOCTYPE html> | |
<meta charset="utf-8"> | |
<body> | |
<script src="//d3js.org/d3.v4.min.js"></script> | |
<script> | |
var width = 960, | |
height = 500; | |
var svg = d3.select("body").append("svg") | |
.attr("width", width) | |
.attr("height", height); | |
var defs = svg.append("defs"); | |
var background = svg.append("g") | |
.attr("class", "dots"); | |
// r=0 is a bug in Chrome | |
var radius = d3.scaleSqrt() | |
.range([1e-9, 6]); | |
var colors = ["yellow", "magenta", "cyan", "black"], | |
rotation = [0, -15, 15, 45]; | |
var patterns = defs.selectAll("pattern") | |
.data(colors) | |
.enter() | |
.append("pattern") | |
.attr("id", Object) | |
.attr("patternUnits", "userSpaceOnUse") | |
.attr("width", 12) | |
.attr("height", 12) | |
.append("circle") | |
.attr("fill", Object) | |
.attr("cx", 6) | |
.attr("cy", 6); | |
defs.append("clipPath") | |
.attr("id", "clip") | |
.append("rect") | |
.attr("width", width / 5) | |
.attr("height", height / 5); | |
svg.append("g").attr("clip-path", "url(#clip)") | |
.attr("transform", "translate(" + (width * 2 / 5) + " " + (height * 2 / 5) + ")") | |
.append("g") | |
.attr("class", "dots") | |
.attr("transform", "scale(0.1 0.1)") | |
.append("rect") | |
.attr("width", width * 2) | |
.attr("height", height * 2) | |
.attr("fill", "#fff"); | |
d3.selectAll(".dots") | |
.selectAll(".color") | |
.data(colors) | |
.enter() | |
.append("rect") | |
.attr("class", "color") | |
.attr("width", width * 4) | |
.attr("height", width * 4) | |
.attr("x", width * -3 / 2) | |
.attr("y", width * -3 / 2) | |
.style("mix-blend-mode", "multiply") | |
.attr("fill", function(d){ | |
return "url(#" + d + ")"; | |
}) | |
.attr("transform", function(d, i){ | |
return rotation[i] ? "rotate(" + rotation[i] + " " + (width / 2) + " " + (height / 2) + ")" : null; | |
}); | |
d3.timer(function(t){ | |
t = t % 16000 / 8000; | |
if (t > 1) { | |
t = 2 - t; | |
} | |
var cmyk = rgbToCmyk(d3.color(d3.interpolateRainbow(t))); | |
patterns.attr("r", function(d){ | |
return radius(cmyk[d]); | |
}); | |
}); | |
function rgbToCmyk(rgb) { | |
var r = rgb.r / 255, | |
g = rgb.g / 255, | |
b = rgb.b / 255, | |
k = 1 - Math.max(r, g, b); | |
return { | |
cyan: (1 - r - k) / (1 - k), | |
magenta: (1 - g - k) / (1 - k), | |
yellow: (1 - b - k) / (1 - k), | |
black: k | |
}; | |
} | |
</script> |
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