31:T644,viewof settings = { const form = html``; const setFormValue = () => { form.value = { date: form.date.valueAsDate || new Date(), model: form.model.value }; // TODO: Report on talk.observablehq.com, this isn't documented properly anywhere form.dispatchEvent(new CustomEvent("input")); } const changeDate = (delta) => { const date = form.date.valueAsDate; // TODO: Fix DST bug (e.g. on Mar 31, 2019) date.setDate(date.getDate() + delta); form.date.valueAsDate = date || new Date(); setFormValue(); } let changeLoop; const startChangeLoop = (delta, interval = 100) => { changeLoop = setInterval(() => changeDate(delta), interval); } form.onchange = () => setFormValue(); form.date.oninput = () => form.value.date = form.date.valueAsDate; form.decrement.onclick = () => changeDate(-1); form.increment.onclick = () => changeDate(1); form.decrement.onmousedown = () => startChangeLoop(-1); form.increment.onmousedown = () => startChangeLoop(1); document.onmouseup = () => clearInterval(changeLoop); setFormValue(); return form; }32:T660,planetPositionsOnDate = { const d = settings.date || new Date(); const ld = luxon.DateTime.fromJSDate(d); const mLater = ld.plus({months: 1}); const julianEphemerisDay = astronomia.julian.DateToJDE(d); const julianNextMonth = astronomia.julian.DateToJDE(mLater.toJSDate()); // const endDate = ld.plus({years: 1}); // const nextYearDates = []; // for (let dd = ld; dd < endDate; dd = dd.plus({days: 4})) { // nextYearDates.push(dd.toJSDate()); // } const nextYear = mLater return Object.keys(planets) .reduce((positions, planet) => { let endDate = ld.plus({days: orbitalPeriods[planet]}); let intervals = luxon.Interval.fromDateTimes(ld, endDate).divideEqually(64); let splitSize = intervals[0].toDuration(); let nextMonth = ld.plus({months: 1}); let nextMonthIntervals = luxon.Interval.fromDateTimes(ld, nextMonth).splitBy(splitSize); let nextYears = intervals.map((cd) => { return planets[planet].position2000(astronomia.julian.DateToJDE(cd.end.toJSDate())); }); let nextMonthPos = nextMonthIntervals.map((cd) => { return planets[planet].position2000(astronomia.julian.DateToJDE(cd.end.toJSDate())); }); let curDay = planets[planet].position2000(julianEphemerisDay); nextYears.unshift(curDay); nextMonthPos.unshift(curDay); positions[planet]= { 'day': curDay, 'later': planets[planet].position2000(julianNextMonth), 'nextYears': nextYears, 'nextMonthPos': nextMonthPos, } return positions; }, {}) }33:T1295, { const [w, h] = [canvasSize, canvasSize]; const padding = 20; const ringWidth = 15; const maxRadius = 6; const ctx = DOM.context2d(w, h); // Draw background ctx.fillStyle = '#222'; ctx.fillRect(0, 0, w, h); // Draw sun ctx.arc(w/2, h/2, maxRadius, 0, 2 * Math.PI); ctx.fillStyle = celestialBodies['sun'].color; ctx.fill(); let base = 10; let adjRangeFn = (r) => { if (logBase == 1) { return r; } return Math.log(r/logBase) // return r/logBase; } ; let maxRange = planetPositionsOnDate['neptune']['day'].range; let adjMaxRange = adjRangeFn(maxRange); let scaleRange = ((w/2) - maxRadius)/adjMaxRange; let drawPts = (poss) => { let pts = poss.map((p) => { // ctx.strokeStyle = "green"; // ctx.setLineDash([2, 4]); const a = p.lon; // const angleInDeg = Math.round((a * 180) / Math.PI); const adjRange = adjRangeFn(p.range); const range = adjRange * scaleRange; return {x: w/2 + Math.cos(a)*range, y: h/2 - Math.sin(a)*range}; }); ctx.moveTo(pts[0].x, pts[0].y); ctx.beginPath(); pts.map(pt => ctx.lineTo(pt.x, pt.y)); // pts.map(pt => { // ctx.beginPath(); // ctx.arc(pt.x, pt.y, 2, 0, Math.PI*2) // ctx.fill(); // ctx.closePath(); // }); ctx.stroke(); ctx.closePath(); }; // Draw planets const table = {}; let drawPlanet = (p, size, color) => { ctx.fillStyle = color; ctx.strokeStyle = color; const a = p.lon; const [x, y] = [Math.cos(a), Math.sin(a)]; // Draw scaled “real” position const adjRange = adjRangeFn(p.range); const range = adjRange * scaleRange; ctx.beginPath(); ctx.arc(w/2 + x * range, h/2 - y * range, size, 0, 2 * Math.PI); ctx.closePath(); } // drawPlanet(equinoxEarth, maxRadius*.2, "black"); // ctx.stroke(); // ctx.moveTo(w/2, w/2); // ctx.lineTo(w/2, 0); // ctx.stroke(); Object.keys(planetPositionsOnDate).forEach((planetName) => { const geocentric = settings.model === 'geocentric'; const name = planetName === 'earth' && geocentric ? 'sun': planetName; const planet = planetPositionsOnDate[planetName]['day']; const planet2 = planetPositionsOnDate[planetName]['later'] // const a = planet.lon; // const angleInDeg = Math.round((a * 180) / Math.PI); // const [x, y] = [Math.cos(a), Math.sin(a)]; ctx.beginPath(); const planetSize = maxRadius * celestialBodies[name].relativeSize; // Draw scaled “real” position // const adjRange = adjRangeFn(planet.range); // const range = adjRange * scaleRange; // table[name] = {pr: planet.range, adjRange, range, a, angleInDeg, x, y}; const textOpacity = Math.min(1, scaleRange/50); // ctx.fillStyle = `rgba(200, 200, 200, ${textOpacity})`; ctx.fillStyle = celestialBodies[name].color; // ctx.strokeStyle = `rgba(200, 200, 200, 1)`; // ctx.beginPath(); // ctx.lineWidth = 1; // ctx.arc(w/2 + x * range, h/2 - y * range, planetSize, 0, 2 * Math.PI); // ctx.stroke(); // ctx.fill(); // ctx.fillText(`${name} ${angleInDeg}°`, w/2 + x * range, h/2 - y * range - 10); drawPlanet(planet, planetSize, celestialBodies[name].color); ctx.fill(); ctx.stroke(); drawPlanet(planet2, planetSize, celestialBodies[name].color); // const a2 = planet2.lon; // //const angleInDeg2 = Math.round((a2 * 180) / Math.PI); // const [x2, y2] = [Math.cos(a2), Math.sin(a2)]; // const adjRange2 = adjRangeFn(planet2.range); // const range2 = adjRange2 * scaleRange; // ctx.beginPath(); // ctx.lineWidth = 1; // ctx.arc(w/2 + x2 * range2, h/2 - y2 * range2, planetSize, 0, 2 * Math.PI); // ctx.strokeStyle = celestialBodies[name].color; // ctx.closePath(); ctx.stroke(); // Draw orbit to 1 month in future // This is an inaccurate representation, it assumes circular orbits // ctx.beginPath() // ctx.arc(w/2, h/2, range, -a, -a2, true); // ctx.stroke(); // Draw full orbit // ctx.beginPath(); ctx.setLineDash([5, 7]); ctx.lineWidth = 0.75; // Assume circular (not accurate) // ctx.arc(w/2, h/2, range, 0, Math.PI*2, true); // Use future data drawPts(planetPositionsOnDate[planetName]['nextYears']); ctx.setLineDash([]); ctx.lineWidth = 1; drawPts(planetPositionsOnDate[planetName]['nextMonthPos']); // ctx.arcTo(x, y, x2, y2, range); // ctx.fill(); // ctx.fillText(`${name} ${angleInDeg}°`, w/2 + x * range, h/2 - y * range - 10); }); console.table(table); return ctx.canvas; return ctx.canvas }34:[] 2f:{"title":"Planetary Positions","cells":[{"id":0,"value":"md`# Planetary Positions\n\nForked from [Projecting Planetary Positions on a Ring](https://observablehq.com/@raphaelsaunier/projecting-planetary-positions-on-a-ring) (goofed on the forking..., TODO: fix it so it's a real fork)\n`","pinned":false,"hidden":false,"mode":"ojs"},{"id":6,"value":"astronomia = require('https://raphaelsaunier.com/observable/astronomia.js')","pinned":true,"hidden":false,"mode":"ojs"},{"id":27,"value":"celestialBodies = ({\n sun: {\n color: \"#F8E71C\", // Used to guide th\n relativeSize: 1,\n symbol: \"☉\" // Not used anywhere\n },\n mercury: {\n color: \"#CAB19A\",\n relativeSize: 0.3,\n symbol: \"☿\"\n },\n venus: {\n color: \"#F2D798\",\n relativeSize: 0.3,\n symbol: \"♀\"\n },\n earth: {\n color: \"#40AED7\",\n relativeSize: 0.4,\n symbol: \"♁\"\n },\n mars: {\n color: \"#E9862E\",\n relativeSize: 0.4,\n symbol: \"♂\"\n },\n jupiter: {\n \tcolor: \"#E9B092\",\n relativeSize: 0.9,\n symbol: \"♃\"\n },\n saturn: {\n color: \"#FCDBB5\",\n relativeSize: 0.8,\n symbol: \"♄\"\n },\n uranus: {\n color: \"#56CDEA\",\n relativeSize: 0.6,\n symbol: \"⛢\"\n },\n neptune: {\n \tcolor: \"#1A88CE\",\n\trelativeSize: 0.6,\n symbol: \"♆\"\n }\n})","pinned":false,"hidden":false,"mode":"ojs"},{"id":11,"value":"planetNames = ['mercury', 'venus', 'earth', 'mars', 'jupiter', 'saturn', 'uranus', 'neptune'];","pinned":true,"hidden":false,"mode":"ojs"},{"id":9,"value":"planets = Object.keys(celestialBodies)\n\t.filter(body => body !== 'sun')\n\t.reduce((planets, planet) => {\n const data = astronomia.data['vsop87B' + planet];\n planets[planet] = new astronomia.planetposition.Planet(data)\n return planets;\n }, {})","pinned":true,"hidden":false,"mode":"ojs"},{"id":21,"value":"$31","pinned":false,"hidden":false,"mode":"ojs"},{"id":54,"value":"// luxon = require('https://bundle.run/luxon@1.16.0')\n luxon = require(\"luxon@1/build/amd/luxon.js\")","pinned":false,"hidden":false,"mode":"ojs"},{"id":103,"value":"// Debug helper to ensure that the projections are correct\nviewof logBase = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":123,"value":"logBase","pinned":true,"hidden":false,"mode":"ojs"},{"id":229,"value":"// From https://nssdc.gsfc.nasa.gov/planetary/factsheet/\norbitalPeriods = ({\n 'mercury': 88.0,\n 'venus': 224.7,\n 'earth': 365.2,\n 'mars': 687.0,\n 'jupiter': 4331,\n 'saturn': 10747,\n 'uranus': 30589,\n 'neptune': 59800})\n","pinned":false,"hidden":false,"mode":"ojs"},{"id":18,"value":"$32","pinned":false,"hidden":false,"mode":"ojs"},{"id":294,"value":"equinoxEarth = planets['earth'].position2000(astronomia.solstice.december(2019))","pinned":true,"hidden":false,"mode":"ojs"},{"id":15,"value":"$33","pinned":false,"hidden":false,"mode":"ojs"},{"id":31,"value":"// Debug helper to ensure that the projections are correct\nviewof scaleRange2 = html``","pinned":true,"hidden":false,"mode":"ojs"},{"id":35,"value":"viewof canvasSize = html``","pinned":true,"hidden":false,"mode":"ojs"},{"id":49,"value":"md`Based on : https://observablehq.com/@raphaelsaunier/projecting-planetary-positions-on-a-ring`","pinned":true,"hidden":false,"mode":"ojs"},{"id":141,"value":"viewof logBase2 = html``","pinned":true,"hidden":false,"mode":"ojs"},{"id":137,"value":"{\nlet adjRangeFn = (r, b) => { return Math.log10(r)/Math.log10(b) };\n return Array(10).fill(0).map(\n (_, i) => {\n return Object.keys(planetPositionsOnDate).map((p) => {\n return adjRangeFn(planetPositionsOnDate[p]['day'].range + 0.6, i + 2)\n // return p\n });\n }\n );\n}\n","pinned":true,"hidden":false,"mode":"ojs"},{"id":233,"value":"ld = luxon.DateTime.local()","pinned":true,"hidden":false,"mode":"ojs"},{"id":239,"value":"end = ld.plus({days: orbitalPeriods['mars']});","pinned":true,"hidden":false,"mode":"ojs"},{"id":260,"value":"resDate = orbitalPeriods['mars'] / 64","pinned":true,"hidden":false,"mode":"ojs"},{"id":241,"value":"orbInterval = luxon.Interval.fromDateTimes(ld,end);","pinned":true,"hidden":false,"mode":"ojs"},{"id":263,"value":"orbInterval.divideEqually(64);","pinned":true,"hidden":false,"mode":"ojs"},{"id":245,"value":"dur = orbInterval.toDuration()","pinned":true,"hidden":false,"mode":"ojs"},{"id":249,"value":"dur.as('days');","pinned":true,"hidden":false,"mode":"ojs"}],"files":"$W34","stdlib":"1","titling":"auto"}