Brian Picciano
3 years ago
parent
21fe465deb
commit
9be52bdaa4
@ -0,0 +1,402 @@ |
||||
--- |
||||
title: >- |
||||
Visualization 6 |
||||
description: >- |
||||
Eat your heart out, Conway! |
||||
series: viz |
||||
tags: tech art |
||||
--- |
||||
|
||||
<script type="text/javascript"> |
||||
|
||||
function randn(n) { |
||||
return Math.floor(Math.random() * n); |
||||
} |
||||
|
||||
const w = 100; |
||||
const h = 50; |
||||
|
||||
class Canvas { |
||||
constructor(canvasDOM) { |
||||
this.dom = canvasDOM; |
||||
this.ctx = canvasDOM.getContext("2d"); |
||||
|
||||
// expand canvas element's width to match parent. |
||||
this.dom.width = this.dom.parentElement.offsetWidth; |
||||
|
||||
// rectSize must be an even number or the pixels don't display nicely. |
||||
this.rectSize = Math.floor(this.dom.width / w /2) * 2; |
||||
|
||||
this.dom.width = w * this.rectSize; |
||||
this.dom.height = h * this.rectSize; |
||||
} |
||||
|
||||
rectSize() { |
||||
return Math.floor(this.dom.width / w); |
||||
} |
||||
} |
||||
|
||||
class Layer { |
||||
constructor(className, newEl, { |
||||
maxNewElsPerTick = 10, |
||||
ageOfDeath = 60, |
||||
neighborBonusScalar = 1, |
||||
layerBonusScalar = 1, |
||||
chaos = 0, |
||||
} = {}) { |
||||
this.className = className; |
||||
this.els = {}; |
||||
this.diff = {}; |
||||
|
||||
this.newEl = newEl; |
||||
this.maxNewElsPerTick = maxNewElsPerTick; |
||||
this.ageOfDeath = ageOfDeath; |
||||
this.neighborBonusScalar = neighborBonusScalar; |
||||
this.layerBonusScalar = layerBonusScalar; |
||||
this.chaos = chaos; |
||||
} |
||||
|
||||
_normCoord(coord) { |
||||
if (typeof coord !== 'string') coord = JSON.stringify(coord); |
||||
return coord; |
||||
} |
||||
|
||||
get(coord) { |
||||
return this.els[this._normCoord(coord)]; |
||||
} |
||||
|
||||
getAll() { |
||||
return Object.values(this.els); |
||||
} |
||||
|
||||
set(coord, el) { |
||||
this.diff[this._normCoord(coord)] = {action: "set", coord: coord, ...el}; |
||||
} |
||||
|
||||
unset(coord) { |
||||
this.diff[this._normCoord(coord)] = {action: "unset"}; |
||||
} |
||||
|
||||
applyDiff() { |
||||
for (const coordStr in this.diff) { |
||||
const el = this.diff[coordStr]; |
||||
delete this.diff[coordStr]; |
||||
|
||||
if (el.action == "set") { |
||||
delete el.action; |
||||
this.els[coordStr] = el; |
||||
} else { |
||||
delete this.els[coordStr]; |
||||
} |
||||
} |
||||
} |
||||
|
||||
update(state, prevLayer) { |
||||
// Apply diff from previous update first. The diff can't be applied last |
||||
// because it needs to be present during the draw phase. |
||||
this.applyDiff(); |
||||
|
||||
const allEls = this.getAll().sort(() => Math.random() - 0.5); |
||||
|
||||
if (allEls.length == 0) { |
||||
const nEl = this.newEl([]) |
||||
nEl.tick = state.tick; |
||||
this.set([w/2, h/2], nEl); |
||||
return; |
||||
} |
||||
|
||||
let newEls = 0; |
||||
for (const el of allEls) { |
||||
const nCoord = randEmptyNeighboringCoord(this, el.coord); |
||||
if (!nCoord) continue; // el has no empty neighboring spots |
||||
|
||||
const nEl = this.newEl(neighboringElsOf(this, nCoord)) |
||||
nEl.tick = state.tick; |
||||
this.set(nCoord, nEl); |
||||
|
||||
newEls++; |
||||
if (newEls >= this.maxNewElsPerTick) break; |
||||
} |
||||
|
||||
for (const el of allEls) { |
||||
const age = state.tick - el.tick; |
||||
const neighborBonus = neighboringElsOf(this, el.coord).length * this.neighborBonusScalar; |
||||
|
||||
const layerBonus = prevLayer |
||||
? neighboringElsOf(prevLayer, el.coord, true).length * this.layerBonusScalar |
||||
: 0; |
||||
|
||||
const chaos = (this.chaos > 0) ? randn(this.chaos) : 0; |
||||
|
||||
if (age - neighborBonus - layerBonus + chaos >= this.ageOfDeath) { |
||||
this.unset(el.coord); |
||||
} |
||||
} |
||||
} |
||||
|
||||
draw(canvas) { |
||||
for (const coordStr in this.diff) { |
||||
const el = this.diff[coordStr]; |
||||
const coord = JSON.parse(coordStr); |
||||
|
||||
if (el.action == "set") { |
||||
canvas.ctx.fillStyle = `hsl(${el.h}, ${el.s}, ${el.l})`; |
||||
canvas.ctx.fillRect( |
||||
coord[0]*canvas.rectSize, coord[1]*canvas.rectSize, |
||||
canvas.rectSize, canvas.rectSize, |
||||
); |
||||
|
||||
} else { |
||||
canvas.ctx.clearRect( |
||||
coord[0]*canvas.rectSize, coord[1]*canvas.rectSize, |
||||
canvas.rectSize, canvas.rectSize, |
||||
); |
||||
} |
||||
} |
||||
} |
||||
} |
||||
|
||||
const neighbors = [ |
||||
[-1, -1], [0, -1], [1, -1], |
||||
[-1, 0], /* [0, 0], */ [1, 0], |
||||
[-1, 1], [0, 1], [1, 1], |
||||
]; |
||||
|
||||
function neighborsOf(coord) { |
||||
return neighbors.map((n) => { |
||||
let nX = coord[0]+n[0]; |
||||
let nY = coord[1]+n[1]; |
||||
nX = (nX + w) % w; |
||||
nY = (nY + h) % h; |
||||
return [nX, nY]; |
||||
}); |
||||
} |
||||
|
||||
function randEmptyNeighboringCoord(layer, coord) { |
||||
const neighbors = neighborsOf(coord).sort(() => Math.random() - 0.5); |
||||
for (const nCoord of neighbors) { |
||||
if (!layer.get(nCoord)) return nCoord; |
||||
} |
||||
return null; |
||||
} |
||||
|
||||
function neighboringElsOf(layer, coord, includeCoord = false) { |
||||
const neighboringEls = []; |
||||
|
||||
const neighboringCoords = neighborsOf(coord); |
||||
if (includeCoord) neighboringCoords.push(coord); |
||||
|
||||
for (const nCoord of neighboringCoords) { |
||||
const el = layer.get(nCoord); |
||||
if (el) neighboringEls.push(el); |
||||
} |
||||
return neighboringEls; |
||||
} |
||||
|
||||
const drift = 30; |
||||
function mkNewEl(l) { |
||||
return (nEls) => { |
||||
const s = "100%"; |
||||
if (nEls.length == 0) { |
||||
return { |
||||
h: randn(360), |
||||
s: s, |
||||
l: l, |
||||
}; |
||||
} |
||||
|
||||
// for each h (which can be considered as degrees around a circle) break the h |
||||
// down into x and y vectors, and add those up separately. Then find the angle |
||||
// between those two resulting vectors, and that's the "average" h value. |
||||
let x = 0; |
||||
let y = 0; |
||||
nEls.forEach((el) => { |
||||
const hRad = el.h * Math.PI / 180; |
||||
x += Math.cos(hRad); |
||||
y += Math.sin(hRad); |
||||
}); |
||||
|
||||
let h = Math.atan2(y, x); |
||||
h = h / Math.PI * 180; |
||||
|
||||
// apply some random drift, normalize |
||||
h += (Math.random() * drift * 2) - drift; |
||||
h = (h + 360) % 360; |
||||
|
||||
return { |
||||
h: h, |
||||
s: s, |
||||
l: l, |
||||
}; |
||||
} |
||||
} |
||||
|
||||
class Universe { |
||||
constructor(canvasesByClass, layers) { |
||||
this.canvasesByClass = canvasesByClass; |
||||
this.state = { |
||||
tick: 0, |
||||
layers: layers, |
||||
}; |
||||
} |
||||
|
||||
update() { |
||||
this.state.tick++; |
||||
let prevLayer; |
||||
this.state.layers.forEach((layer) => { |
||||
layer.update(this.state, prevLayer); |
||||
prevLayer = layer; |
||||
}); |
||||
} |
||||
|
||||
draw() { |
||||
this.state.layers.forEach((layer) => { |
||||
if (!this.canvasesByClass[layer.className]) return; |
||||
this.canvasesByClass[layer.className].forEach((canvas) => { |
||||
layer.draw(canvas); |
||||
}); |
||||
}); |
||||
} |
||||
} |
||||
|
||||
</script> |
||||
|
||||
<style> |
||||
|
||||
.canvasContainer { |
||||
display: grid; |
||||
margin-bottom: 2rem; |
||||
text-align: center; |
||||
} |
||||
|
||||
canvas { |
||||
border: 1px dashed #AAA; |
||||
width: 100%; |
||||
grid-area: 1/1/2/2; |
||||
} |
||||
|
||||
</style> |
||||
|
||||
<div class="canvasContainer"> |
||||
<canvas class="layer1"></canvas> |
||||
<canvas class="layer2"></canvas> |
||||
</div> |
||||
|
||||
<div class="row"> |
||||
|
||||
<div class="columns six"> |
||||
<h3>Bottom Layer</h3> |
||||
<div class="canvasContainer"><canvas class="layer1"></canvas></div> |
||||
<div class="layer1 layerParams"> |
||||
<label>Max New Elements Per Tick</label><input type="text" param="maxNewElsPerTick" /> |
||||
<label>Age of Death</label><input type="text" param="ageOfDeath" /> |
||||
<label>Neighbor Bonus Scalar</label><input type="text" param="neighborBonusScalar" /> |
||||
</div> |
||||
</div> |
||||
|
||||
<div class="columns six"> |
||||
<h3>Top Layer</h3> |
||||
<div class="canvasContainer"><canvas class="layer2"></canvas></div> |
||||
<div class="layer2 layerParams"> |
||||
<label>Max New Elements Per Tick</label><input type="text" param="maxNewElsPerTick" /> |
||||
<label>Age of Death</label><input type="text" param="ageOfDeath" /> |
||||
<label>Neighbor Bonus Scalar</label><input type="text" param="neighborBonusScalar" /> |
||||
<label>Layer Bonus Scalar</label><input type="text" param="layerBonusScalar" /> |
||||
</div> |
||||
</div> |
||||
|
||||
</div> |
||||
|
||||
This visualization is essentially the same as the previous, except that each |
||||
layer now operates with different parameters than the other, allowing each to |
||||
exhibit different behavior. |
||||
|
||||
Additionally, the top layer has been made to be responsive to the bottom, via a |
||||
new mechanism where the age of an element on the top layer can be extended based |
||||
on the number of bottom layer elements it neighbors. |
||||
|
||||
Finally, the UI now exposes the actual parameters which are used to tweak the |
||||
behavior of each layer. Modifying any parameter will change the behavior of the |
||||
associated layer in real-time. The default parameters have been chosen such that |
||||
the top layer is now rather dependent on the bottom for sustenance, although it |
||||
can venture away to some extent. However, by playing the parameters yourself you |
||||
can find other behaviors and interesting cause-and-effects that aren't |
||||
immediately obvious. Try it! |
||||
|
||||
An explanation of the parameters is as follows: |
||||
|
||||
On each tick, up to `maxNewElements` are created in each layer, where each new |
||||
element neighbors an existing one. |
||||
|
||||
Additionally, on each tick, _all_ elements in a layer are iterated through. Each |
||||
one's age is determined as follows: |
||||
|
||||
``` |
||||
age = (currentTick - birthTick) |
||||
age -= (numNeighbors * neighborBonusScalar) |
||||
age -= (numBottomLayerNeighbors * layerBonusScalar) // only for top layer |
||||
``` |
||||
|
||||
If an element's age is greater than or equal to the `ageOfDeath` for that layer, |
||||
then the element is removed. |
||||
|
||||
<script> |
||||
|
||||
const canvasesByClass = {}; |
||||
[...document.getElementsByTagName("canvas")].forEach((canvasDOM) => { |
||||
|
||||
const canvas = new Canvas(canvasDOM); |
||||
canvasDOM.classList.forEach((name) => { |
||||
if (!canvasesByClass[name]) canvasesByClass[name] = []; |
||||
canvasesByClass[name].push(canvas); |
||||
}) |
||||
}); |
||||
|
||||
const layers = [ |
||||
|
||||
new Layer("layer1", mkNewEl("90%"), { |
||||
maxNewElsPerTick: 2, |
||||
ageOfDeath: 30, |
||||
neighborBonusScalar: 50, |
||||
}), |
||||
|
||||
new Layer("layer2", mkNewEl("50%", ), { |
||||
maxNewElsPerTick: 10, |
||||
ageOfDeath: 1, |
||||
neighborBonusScalar: 15, |
||||
layerBonusScalar: 5, |
||||
}), |
||||
|
||||
]; |
||||
|
||||
for (const layer of layers) { |
||||
document.querySelectorAll(`.${layer.className}.layerParams > input`).forEach((input) => { |
||||
const param = input.getAttribute("param"); |
||||
|
||||
// pre-fill input values |
||||
input.value = layer[param]; |
||||
|
||||
input.onchange = () => { |
||||
console.log(`setting ${layer.className}.${param} to ${input.value}`); |
||||
layer[param] = input.value; |
||||
}; |
||||
}); |
||||
} |
||||
|
||||
const universe = new Universe(canvasesByClass, layers); |
||||
|
||||
const requestAnimationFrame = |
||||
window.requestAnimationFrame || |
||||
window.mozRequestAnimationFrame || |
||||
window.webkitRequestAnimationFrame || |
||||
window.msRequestAnimationFrame; |
||||
|
||||
function doTick() { |
||||
universe.update(); |
||||
universe.draw(); |
||||
requestAnimationFrame(doTick); |
||||
} |
||||
|
||||
doTick(); |
||||
|
||||
</script> |
||||
Loading…
Reference in new issue