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273 | /*
BSD Zero Clause License
Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
*/
window.addEventListener('load', () => {
'use strict'
const canvas = document.getElementById('fractalCanvas');
const graphicsContext = canvas.getContext('2d');
function hexColorToRgb(hexCol) {
return [
parseInt(hexCol.substring(1, 3), 16) / 255,
parseInt(hexCol.substring(3, 5), 16) / 255,
parseInt(hexCol.substring(5, 7), 16) / 255,
]
}
function forEachIn(htmlCollection, ...args) {
Array.from(htmlCollection).forEach(...args);
}
class Operation {
constructor(params) {
this.weight = parseInt(params.weight);
this.color = hexColorToRgb(params.color);
}
mixColor(prevColor) {
for (let i = 0; i < 3; i++) {
prevColor[i] = (prevColor[i] + this.color[i]) / 2;
}
return prevColor;
}
};
class OpRotation extends Operation {
constructor(params) {
super(params);
const angle = params.degrees * Math.PI / 180;
this.sinTheta = Math.sin(angle);
this.cosTheta = Math.cos(angle);
}
stepPos(coords) {
const x = coords[0] * this.cosTheta - coords[1] * this.sinTheta;
const y = coords[0] * this.sinTheta + coords[1] * this.cosTheta;
coords[0] = x;
coords[1] = y;
return coords;
}
};
class OpSpiral extends Operation {
constructor(params) {
super(params);
this.maxAngle = params.degrees * Math.PI / 180;
}
stepPos(coords) {
const angleHere = this.maxAngle * Math.sqrt(
coords[0] * coords[0] + coords[1] * coords[1]);
const sinTheta = Math.sin(angleHere);
const cosTheta = Math.cos(angleHere);
const x = coords[0] * cosTheta - coords[1] * sinTheta;
const y = coords[0] * sinTheta + coords[1] * cosTheta;
coords[0] = x;
coords[1] = y;
return coords;
}
};
class OpSine extends Operation {
constructor(params) {
super(params);
this.mulBy = Math.PI * 2 / params.divisor;
}
stepPos(coords) {
coords[0] = Math.sin(coords[0] * this.mulBy);
coords[1] = Math.sin(coords[1] * this.mulBy);
return coords;
}
};
class OpCoreShape extends Operation {
constructor(params) {
super(params);
switch (params.shape) {
case 'pentagon':
this.sides = 5;
this.scaleFactor = (3 - Math.sqrt(5)) / 2;
break;
case 'hexagon':
this.sides = 6;
this.scaleFactor = 1/3;
break;
default:
this.sides = 3;
this.scaleFactor = 0.5;
}
this.points = [];
const sf = 1 - this.scaleFactor;
for (let i = 0; i < this.sides; i++) {
const angle = i * Math.PI * 2 / this.sides + Math.PI;
this.points.push([Math.sin(angle) * sf, Math.cos(angle) * sf]);
}
}
stepPos(coords) {
const tarPoint = this.points[
Math.floor(Math.random() * this.sides)];
coords[0] = coords[0] * this.scaleFactor + tarPoint[0];
coords[1] = coords[1] * this.scaleFactor + tarPoint[1];
return coords;
}
};
const availableOperators = {
OpRotation,
OpSpiral,
OpSine,
OpCoreShape,
};
function paramsFromControl(section) {
const params = {};
const ctrls = section.querySelectorAll(
'input[data-param-name], select[data-param-name]');
ctrls.forEach(c => {
params[c.dataset.paramName] = c.value;
});
return params;
}
let generatorAnimId = null;
let genFunc = null;
// collect control elements
let operatorControlSections;
const generatorParamControls = {};
const buttons = {};
{
const controlRoot = document.getElementById('fractalCtrls');
const sectionList = Array.from(
controlRoot.getElementsByClassName('control-section'));
operatorControlSections = sectionList.filter(
s => s.dataset?.operation != 'Generation');
const generationSection = sectionList.filter(
s => s.dataset?.operation == 'Generation')[0];
forEachIn(generationSection.getElementsByTagName('input'),
e => generatorParamControls[e.dataset.paramName] = e);
forEachIn(generationSection.getElementsByTagName('button'),
b => buttons[b.dataset.func] = b);
buttons.pause.disabled = true;
buttons.resume.disabled = true;
}
function beginGenerate() {
if (generatorAnimId) {
window.cancelAnimationFrame(generatorAnimId);
generatorAnimId = null;
}
const operatorList = [];
// collect parameters and create operators.
operatorControlSections.forEach(section => {
const opType = section.dataset.operation;
const op = new availableOperators['Op' + opType](
paramsFromControl(section));
const curOpCount = operatorList.length;
operatorList.length = curOpCount + op.weight;
operatorList.fill(op, curOpCount, curOpCount + op.weight);
});
const pointsPerFrame = generatorParamControls.points.valueAsNumber;
const bgColor = generatorParamControls.background.value;
canvas.style.background = bgColor;
// clear canvas and set up coord system.
canvas.width = canvas.clientWidth;
canvas.height = canvas.clientHeight;
graphicsContext.resetTransform();
graphicsContext.clearRect(0, 0, canvas.width, canvas.height);
const sideLen = Math.min(canvas.width, canvas.height);
graphicsContext.translate(canvas.width / 2, canvas.height / 2);
graphicsContext.scale(sideLen / 2, sideLen / 2);
const pixSize = 0.8 / sideLen;
// start drawing
let point = [Math.random() * 2 - 1, Math.random() * 2 - 1];
let color = [0.0, 0.0, 0.0];
function iterStep() {
const choice = Math.floor(Math.random() * operatorList.length);
const op = operatorList[choice];
op.stepPos(point);
op.mixColor(color);
}
function drawPoint()
{
graphicsContext.fillStyle = `rgba(
${Math.floor(color[0] * 255)},
${Math.floor(color[1] * 255)},
${Math.floor(color[2] * 255)},
0.5)`;
graphicsContext.fillRect(point[0], point[1], pixSize, pixSize);
}
// run it for a bit to get close to the shape
for (let i = 100; i-- > 0;) {
iterStep();
}
function drawFrame() {
for (let i = pointsPerFrame; i-- > 0;) {
iterStep();
drawPoint();
}
generatorAnimId = window.requestAnimationFrame(drawFrame);
}
genFunc = drawFrame;
drawFrame();
}
function updateButtons() {
if (genFunc) {
if (generatorAnimId) {
buttons.pause.disabled = false;
buttons.resume.disabled = true;
} else {
buttons.pause.disabled = true;
buttons.resume.disabled = false;
}
}
}
buttons.generate.addEventListener('click', () => {
beginGenerate();
updateButtons();
});
buttons.pause.addEventListener('click', () => {
if (generatorAnimId) {
window.cancelAnimationFrame(generatorAnimId);
generatorAnimId = null;
}
updateButtons();
});
buttons.resume.addEventListener('click', () => {
if (!generatorAnimId && genFunc) {
generatorAnimId = window.requestAnimationFrame(genFunc);
}
updateButtons();
});
});
|