SVG chart images

/v1/render/* returns a chart as a ready SVG: natal wheel, bi- and tri-wheel, composite, Vedic charts (North, South, East), aspect grid, cosmogram, moon phase, timeline, biorhythm, eclipse path and star map. You send birth data, we compute the chart and draw it. Every route and parameter is in the API reference.

The same drawing code is published as the npm package @astroway/render: if you already hold the chart data, draw the wheel in the browser or on your own server and it matches what the API returns, byte for byte. The API reports the drawing version in the X-Render-Version header.

Request

curl -X POST https://api.astroway.info/v1/render/wheel-western \
  -H "X-Api-Key: $ASTROWAY_KEY" -H "Content-Type: application/json" \
  -d '{"date":"1990-05-15","time":"14:30:00","timezoneOffset":3,"latitude":50.45,"longitude":30.52,
       "options":{"theme":"css","format":"svg"}}' > wheel.svg

format: "svg" returns the file itself; the default json wraps the SVG string in the usual API response. Themes: light, dark, console and css.

The css theme: your site’s colours

With theme: "css" every colour in the SVG is a CSS variable with the light theme’s colour as fallback, for example var(--aw-ring, #222). Inline the SVG into the page’s HTML (not an <img>: variables do not reach inside one) and set the variables:

.chart {
  --aw-chart-bg: transparent;
  --aw-ring: #444;
  --aw-fg: currentColor;
  --aw-aspect-tense: crimson;
}

With no variable set the chart looks exactly like light. A CSS rule on your page beats the variable, so a single element can be recoloured by class.

Variable	Paints
--aw-chart-bg	chart background
--aw-fg, --aw-muted	glyphs and labels, secondary text and ticks
--aw-ring	circles and grid lines
--aw-houses-fill	Vedic chart field, star map disc, eclipse map
--aw-benefic	outer-wheel planets, the lagna in Vedic charts, timeline events without their own colour
--aw-malefic	the retrograde mark ℞, the eclipse path
--aw-aspect-harmonious, --aw-aspect-tense, --aw-aspect-neutral, --aw-aspect-minor, --aw-aspect-quintile	aspect lines and symbols
--aw-moon-shadow, --aw-moon-light	moon phase
--aw-cycle-physical, --aw-cycle-emotional, --aw-cycle-intellectual	biorhythm

Classes and data attributes

In the css theme the Western wheels (wheel-western, bi-wheel, tri-wheel, composite) and the aspect grid carry stable classes. Names are only ever added, never renamed, so styles and scripts can rely on them.

• Wheel: aw-bg, aw-ring, aw-sign aw-sign-leo, aw-sign-line, aw-tick, aw-house-cusp, aw-house-number, axes aw-axis aw-asc (aw-dsc, aw-mc, aw-ic), their labels aw-label aw-axis-label, the title aw-title.
• Planet: a group <g class="aw-planet aw-planet-sun">, plus aw-retrograde when retrograde and aw-layer-1 on the outer wheel. Inside: aw-glyph, aw-retro (the ℞ mark) and aw-planet-tick.
• Aspect: a line aw-aspect aw-aspect-trine; a line between the two charts also has aw-cross-aspect.
• Aspect grid: aw-grid-header, aw-grid-cell, aw-aspect aw-aspect-square, aw-orb.

A planet group has data-planet (sun, north-node, lilith; b-sun on the outer wheel, c-sun on the third) and data-label with the name and position: Mercury 8°00' Taurus, retrograde. Aspect lines and grid cells have data-a and data-b. Highlighting all of a planet’s aspects on hover:

svg.querySelectorAll('.aw-planet').forEach((g) => g.addEventListener('mouseenter', () => {
  const id = g.dataset.planet;
  svg.querySelectorAll('.aw-aspect').forEach((line) =>
    line.classList.toggle('is-on', line.dataset.a === id || line.dataset.b === id));
}));

Your own words: labels

The Western wheels take options.labels: your words for the axis labels, the <title> and <desc> screen readers announce, and the names inside data-label. Absent keys stay in English; we translate nothing for you.

"options": {
  "theme": "css",
  "labels": {
    "asc": "Asc", "mc": "MC", "title": "Birth chart",
    "bodies": { "Sun": "Soleil", "Moon": "Lune" },
    "signs": ["Bélier","Taureau","Gémeaux","Cancer","Lion","Vierge","Balance","Scorpion","Sagittaire","Capricorne","Verseau","Poissons"],
    "retrograde": "rétrograde"
  }
}

bodies is keyed by the English name (Sun, North Node), signs is exactly twelve names starting from Aries, every label up to 40 characters.

Aspects between two charts

/v1/render/bi-wheel with options.crossAspects: true draws the aspects between the inner and the outer chart as dashed lines, the same set POST /v1/synastry returns as crossAspects. A pair with a body that is not drawn is skipped. Off by default.

A chart you already hold instead of birth data

If you already have the chart because you just called POST /v1/chart, send its data as chart instead of birth data and we only draw it. This works on wheel-western, aspect-grid and bi-wheel (there natal.chart and outer.chart, both must be ready charts). The image comes out byte for byte the same as from birth data.

{ "chart": { "planets": [ ... ], "houses": { "cusps": [ ... ], "ascendant": 7.77, "mc": 277.12 }, "aspects": [ ... ] },
  "options": { "theme": "css" } }

No need to strip the extra fields of the response. What gets drawn is checked: 1 to 30 bodies, longitudes 0 to 360, exactly 12 cusps. A body carrying both chart and birth data is refused with 400.

Cost

A /v1/render/* call with birth data costs 10 credits, because the chart is computed. With a ready chart, /v1/render/wheel-western, /v1/render/aspect-grid and /v1/render/bi-wheel cost 1 credit. Theme, classes and labels do not change the price.