Synthetic texture algorithms / Claudio Esperança

Claudio Esperança

Computer Graphics & Visualization @ufrj.br

Workspace

Public

Generative Art

Edited

Jul 31, 2024

5 stars

function paperTexture(options = {}) {

let {

width = 800,

height = 600,

baseAngle = 45,

angleVar = 3,

coarseness = 10,

lengthVariation = 0.2,

layers = 10,

background = "white",

color = "rgb(200,0,0)",

colorVariation = 0.1,

opacity = 0.7,

blur = 2,

randomSeed = 0

} = options;

const sep = coarseness;

baseAngle *= Math.PI / 180;

angleVar *= Math.PI / 180;

const [w, h] = [width + sep * 2, height + sep * 2];

const canvas = DOM.canvas(w, h);

const ctx = canvas.getContext("2d");

const baseColor = d3.hsl(d3.color(color));

const rand = makeRandFunction(randomSeed);

const avgLen = sep;

const pds = new Poisson(

{

shape: [w, h],

minDistance: sep * 0.8,

maxDistance: sep / 0.8,

tries: 15

rand

);

ctx.lineWidth = sep / 4;

const [minv, maxv] = [

Math.max(0.5, 1 - colorVariation),

Math.min(1.5, 1 + colorVariation)

];

ctx.fillStyle = background;

ctx.fillRect(0, 0, w, h);

for (let [x, y] of pds.fill()) {

ctx.beginPath();

const vlen = avgLen * rand(1 - lengthVariation, 1 + lengthVariation);

const ang = baseAngle + rand(-angleVar, angleVar);

const [vx, vy] = [vlen * Math.cos(ang), vlen * Math.sin(ang)];

ctx.moveTo(x - vx, y - vy);

ctx.lineTo(x + vx, y + vy);

let color = d3.hsl(

baseColor.h,

baseColor.s * rand(minv, maxv),

baseColor.l * rand(minv, maxv)

);

color.opacity = opacity;

ctx.strokeStyle = color.formatRgb();

ctx.stroke();

}

const canvas2 = DOM.canvas(width, height);

const ctx2 = canvas2.getContext("2d");

ctx2.filter = `blur(${blur}px)`;

ctx2.drawImage(canvas, 0, 0);

if (layers > 1) {

ctx2.globalAlpha = 0.5;

for (let i = 1; i < layers; i++)

ctx2.drawImage(canvas, rand(-sep, 0), rand(-sep, 0));

}

return canvas2;

}

function fiberTexture(options = {}) {

let {

width = 800,

height = 600,

linewidth = 1,

coarseness = 10,

waviness = 0.2,

background = "white",

color = "black",

colorVariation = 0,

threadLen = 10,

opacity = 0.2,

randomSeed = 0

} = options;

const canvas = DOM.canvas(width, height);

const ctx = canvas.getContext("2d");

const baseColor = d3.hsl(color);

const sep = coarseness;

const avgLen = sep * 2;

const rand = makeRandFunction(randomSeed);

const pds = new Poisson(

{

shape: [width, height],

minDistance: sep * 0.8,

maxDistance: sep / 0.8,

tries: 15

rand

);

ctx.fillStyle = background;

ctx.fillRect(0, 0, width, height);

ctx.lineWidth = linewidth;

const [minv, maxv] = [

Math.max(0.5, 1 - colorVariation),

Math.min(1.5, 1 + colorVariation)

];

for (let [x, y] of pds.fill()) {

let angle = rand(-Math.PI, Math.PI);

let [px, py] = [x, y];

ctx.beginPath();

ctx.moveTo(x, y);

for (let i = 0; i < threadLen; i++) {

const pts = d3.range(3).map((k) => {

const len = sep * 0.3 * rand(0.7, 1 / 0.7);

if (k != 0) angle += Math.PI * 0.25 * rand(-waviness, waviness);

const p = [px + len * Math.cos(angle), py + len * Math.sin(angle)];

[px, py] = p;

return p;

});

ctx.bezierCurveTo(...pts.flat());

}

let color = d3.hsl(

baseColor.h * rand(minv, maxv),

baseColor.s * rand(minv, maxv),

baseColor.l * rand(minv, maxv)

);

color.opacity = opacity;

ctx.strokeStyle = color.formatRgb();

ctx.stroke();

}

return canvas;

}

sampleNoiseTexture = noiseTexture(noiseTexturePresets)

function noiseTexture(options = {}) {

let {

width = 800,

height = 600,

coarseness = 30,

background = "white",

color = "red",

baseSize = 1,

sizeModulation = 1,

aspectModulation = 1,

angleModulation = 1,

hueModulation = 0.5,

lumModulation = 0.5,

primitive = "line",

sizeNoiseAmplitude = 100,

aspectNoiseAmplitude = 100,

angleNoiseAmplitude = 200,

hueNoiseAmplitude = 100,

lumNoiseAmplitude = 200,

opacity = 0.7,

randomSeed = 1,

blur = 0

} = options;

const baseColor = d3.hsl(d3.color(color));

baseColor.opacity = opacity;

const canvas = DOM.canvas(width, height);

const ctx = canvas.getContext("2d");

const sep = coarseness;

const [deltax, deltay] = [sep * 0.5, sep * 0.5];

const size = sep * 0.5 * baseSize;

const rand = makeRandFunction(randomSeed);

const makeNoise = (amplitude) => {

const scale = -Math.log2(amplitude);

return createSimplexNoise({

xScaleLog: scale,

yScaleLog: scale,

octaves: 1,

random: rand

});

};

const sizeNoise = makeNoise(sizeNoiseAmplitude);

const aspectNoise = makeNoise(aspectNoiseAmplitude);

const angleNoise = makeNoise(angleNoiseAmplitude);

const hueNoise = makeNoise(hueNoiseAmplitude);

const lumNoise = makeNoise(lumNoiseAmplitude);

const draw =

primitive == "circle"

? () => {

ctx.beginPath();

ctx.arc(0, 0, 0.5, 0, Math.PI * 2);

ctx.fill();

}

: primitive == "square"

? () => {

ctx.fillRect(-0.5, -0.5, 1, 1);

}

: primitive == "triangle"

? () => {

ctx.beginPath();

ctx.moveTo(-0.5, -0.5);

ctx.lineTo(0.5, 0.5);

ctx.lineTo(-0.5, 0.5);

ctx.fill();

}

: () => {

ctx.beginPath();

ctx.moveTo(-0.25, -0.75);

ctx.lineTo(-0.75, -0.25);

ctx.lineTo(0.25, 0.75);

ctx.lineTo(0.75, 0.25);

ctx.fill();

};

ctx.fillStyle = background;

ctx.fillRect(0, 0, width, height);

for (let x = -deltax; x - deltax <= width; x += deltax) {

for (let y = -deltay; y - deltay <= height; y += deltay) {

ctx.resetTransform();

ctx.translate(x, y);

const ang = angleModulation * angleNoise(x, y) * Math.PI;

ctx.rotate(ang);

const s = 1 + sizeModulation * sizeNoise(x, y);

const a = aspectModulation * aspectNoise(x, y);

ctx.scale(size * s * (1 + a), size * s * (1 - a));

const hfactor = hueModulation * 180 * hueNoise(x, y);

const lfactor = lumModulation * 0.5 * lumNoise(x, y);

ctx.fillStyle = d3

.hsl(baseColor.h + hfactor, baseColor.s, baseColor.l + lfactor, opacity)

.formatRgb();

draw();

}

const canvas2 = DOM.canvas(width, height);

const ctx2 = canvas2.getContext("2d");

ctx2.filter = `blur(${blur}px)`;

ctx2.drawImage(canvas, 0, 0);

return canvas2;

}

presets = FileAttachment("presets@1.json").json()

function collage(images, options = {}) {

const { width = 800, height = 600 } = options;

const canvas = DOM.canvas(width, height);

const ctx = canvas.getContext("2d");

ctx.shadowColor = "black";

ctx.shadowBlur = 20;

const delta = width / images.length;

let x = 0;

for (let img of images) {

ctx.drawImage(img, x, 0, width, height);

x += delta;

}

return canvas;

}

collage([samplePaperTexture, sampleFiberTexture, sampleNoiseTexture])

<br>

## Random stuff

rand = makeRandFunction(randomSeed)

function makeRandFunction(randomSeed) {

const baseRandom = d3.randomLcg(randomSeed);

return (a, b) =>

b === undefined

? a === undefined

? baseRandom()

: baseRandom() * a

: baseRandom() * (b - a) + a;

}

mutable randomSeed = Math.random()

Poisson = require("https://bundle.run/poisson-disk-sampling@2.2.2")

import { createSimplexNoise } from "@esperanc/simplex-noise-exerciser"

import { presetMenu } from "@esperanc/input-presets"

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