Jacobi Elliptic Functions in the Complex PlaneComputing π with the Bailey-Borwein-Plouffe FormulaAdaptive Contouring in Fragment ShadersGrouping Points with Principal Component AnalysisDomain Coloring with Adaptive ContouringDouble Compound Pendulums3D Reaction-Diffusion2D (Non-physical) N-body Gravity with Poisson's EquationPeriodic Planar Three-Body OrbitseasesFinding Roots in the Complex Planeglsl-complexglsl-complex-auto-differentiationpolynomial-rootscomplex-auto-differentiationutilsIntegration
Quasicrystals
Also listed in…
WebGL
function createDrawQuasicrystal(regl) {
return regl({
vert: `
precision highp float;
attribute vec2 aBigTri;
uniform mat3 inverseView3;
varying vec2 xy;
void main () {
// Use an inverse view matrix computed from the x-scale and y-scale
// to pass an x-y pair to the fragment shader
xy = (inverseView3 * vec3(aBigTri, 1)).xy;
gl_Position = vec4(aBigTri, 0, 1);
}`,
frag: `
precision highp float;
uniform float t;
varying vec2 xy;
const float PI = 3.14159265358979323846264;
vec4 color(float t) {
const float ar = 0.50, ag = 0.50, ab = 0.50;
const float br = 0.50, bg = 0.50, bb = 0.50;
const float cr = 1.00, cg = 1.00, cb = 1.00;
const float dr = 0.00, dg = 0.10, db = 0.20;
return vec4(
ar + br * cos(2.0 * PI * (cr * t + dr)),
ag + bg * cos(2.0 * PI * (cg * t + dg)),
ab + bb * cos(2.0 * PI * (cb * t + db)),
1.0
);
}
void main(void) {
const int n = ${N};
const float step = PI / float(n);
float alpha;
for (int i = 0; i < n; i++) {
float theta = float(i) * step;
alpha += cos(cos(theta) * xy.x + sin(theta) * xy.y + t);
}
gl_FragColor = color(alpha * 2.0 / float(n));
}`,
attributes: {
// Render a single big triangle that covers the viewport
aBigTri: [-4, -4, 4, -4, 0, 4]
},
uniforms: {
t: regl.context('time')
},
count: 3,
depth: { enable: false }
});
}
plotContext = {
return createPlotContext(this, {
width: width,
xrange: [-100, 100],
yrange: [-100, 100]
});
}
function createPlotContext(existingContext, opts) {
const xrange = opts.xrange || [-1, 1];
const yrange = opts.yrange || [-1, 1];
const w = opts.width || 640;
const margin =
opts.margin ||
(width < 640 ? { t: 3, r: 0, b: 1, l: 1 } : { t: 5, r: 5, b: 20, l: 40 });
const height = opts.height || Math.max(500, Math.min(900, w * 0.7));
const viewport = { width: w, height, dpi: devicePixelRatio, margin };
const yScale = d3
.scaleLinear()
.domain(xrange)
.range([viewport.height - viewport.margin.b, viewport.margin.t]);
const xScale = constrainLinearScaleAspectRatio(
d3
.scaleLinear()
.domain(yrange)
.range([viewport.margin.l, viewport.width - viewport.margin.r]),
yScale,
1
);
return Object.assign(
existingContext || {
element: d3.create('svg').node()
},
{
viewport,
xScale,
yScale,
currentXScale: xScale.copy(),
currentYScale: yScale.copy()
}
);
}
d3 = require('d3@5')
createREGL = require('regl')
import {
getOrAttachReglFO,
constrainLinearScaleAspectRatio,
createReglViewportConfiguration,
createReglLinearScaleConfiguration,
persistentZoom,
viewportAxes
} from '@rreusser/regl-tools'
isNarrowScreen = width <= 640
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