Hi. I'm Nicolas Lambert, research engineer in geographic information science at CNRS (France). My job is to draw maps and teach cartography at the university. I am a geographer 🌎, and not really a developer 🖥️
Map projectionsh3-jsThe draw() functionsquareProportional symbolsSpike markTypologyChoroplethLayout marksHandle geometriesSVG filters and clipTile markContainersinsetsPath markText markInteractivityTooltipsLegendsCircle markRidgelines mapWhy it's better not to add scalebars to world mapsNight and dayPan and zoomCharging points for electric vehicles in ParisLet's design a "dot cartogram"Hello geovizWorld Population
Symbols
viz.symbol({ fill: "#38896F", r: 50 })
viz.symbol({ symbol: "fist", fill: "#38896F", r: 50 })
viz.tool.symbols()
viz.symbol({
symbol: "clover",
fill: "#38896F",
r: 50,
background: true,
background_fill: "red",
scale: 3,
rotate: 180
})
position = [300, 100]
{
// Container
let svg = viz.create({
width: 500,
domain: world,
zoomable: true
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Square
svg.symbol({
pos: position,
symbol: "heart",
r: 30,
fill: "#38896F"
});
// Render
return svg.render();
}
You can also give a geographic position in latitude and longitude. In this case, set <mark>coords</mark> to "geo". In this case, the symbol move when you zoom in on the map.
sfax = [10.76, 34.741]
{
// Container
let svg = viz.create({
domain: world,
width: 500,
zoomable: true
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Square
svg.symbol({
coords: "geo",
r: 20,
symbol: "human",
pos: sfax,
fill: "#38896F"
});
// Render
return svg.render();
}
{
// Container
let svg = viz.create({
width: 500,
zoomable: true,
domain: world
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Symbols
svg.symbol({
data: world,
width: 10,
r: 10,
stroke: "white",
strokeWidth: 1,
fill: "#38896F"
});
// Render
return svg.render();
}
{
// Container
let svg = viz.create({
width: 500,
zoomable: true,
domain: world
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Spikes
svg.symbol({
data: world,
symbol: "pentagon",
width: 10,
r: 5,
dodge: true,
dodgegap: -0.5,
stroke: "white",
strokeWidth: 1,
fill: "#38896F"
});
// Render
return svg.render();
}
{
// Container
let svg = viz.create({
zoomable: true,
domain: world
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
const typo = viz.tool.typo(world.features.map((d) => d.properties.region));
// Spikes
svg.symbol({
data: world,
symbol: "region",
width: 10,
dodge: true,
r: 10,
stroke: "white",
strokeWidth: 1,
fill: (d) => typo.colorize(d.properties.region)
});
// Render
return svg.render();
}
{
let svg = viz.create({ projection: d3.geoNaturalEarth1(), zoomable: true });
svg.outline();
svg.graticule({ stroke: "white", step: 30 });
svg.path({ datum: world, fill: "white", fillOpacity: 0.3 });
svg.header({ text: "Nuclear Power Plants worldwide" });
svg.footer({
text: "source: https://github.com/cristianst85/GeoNuclearData"
});
svg.symbol({
data,
//dodge: true,
symbol: "nuke",
//fill: "#ebac00",
fill: "black",
background_fill: "#ebac00",
background_fillOpacity: 1,
background_stroke: "black",
background_strokeWidth: 1,
r: 12,
background: true,
tip: true
});
return svg.render();
}
viz.legend.symbol_vertical({ symbol_fill: "#38896F", rotate: 30 })
viz.legend.symbol_vertical({
subtitle: "subtitle",
note: "source",
types: ["pin", "hospital", "flower", "cloud", "human", "tent"],
symbols: ["pin", "hospital", "flower", "cloud", "human", "tent"],
symbol_background: true,
symbol_rotate: 180,
symbol_fill: "#38896F",
symbol_stroke: "none",
symbol_scale: 1,
symbol_size: 20
})
viz.legend.symbol_horizontal({
subtitle: "subtitle",
note: "source",
types: ["pin", "hospital", "flower", "cloud", "human", "tent"],
symbols: ["pin", "hospital", "flower", "cloud", "human", "tent"],
symbol_background: true,
symbol_spacing: 45,
values_textAnchor: "start",
values_dx: 23,
values_dy: -25,
symbol_rotate: 18,
symbol_fill: "#38896F",
symbol_stroke: "none",
symbol_scale: 1,
symbol_size: 20
})
{
// Container
let svg = viz.create({
zoomable: true,
domain: world
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Symbols
svg.symbol({
data: world,
symbol: "region",
order: ["Africa", "America", "Oceania"],
symbols: ["hospital", "flower", "cloud"],
width: 10,
background: true,
fill: "#38896F"
});
svg.legend.symbol_vertical({
pos: [20, 20],
frame: true,
symbol_background: true,
alphabetical: false,
types: ["Africa", "America", "Oceania", "Missing"],
symbols: ["hospital", "flower", "cloud", "missing"]
});
// Render
return svg.render();
}
viz.plot({ type: "symbol" })
The <mark>picto</mark> type allows you to use this mark with the appropriate legend.
viz.plot({ type: "symbol", data: world, symbol: "region" })
viz.plot({
type: "picto",
r: 6.5,
data: world,
fill: "black",
var: "region",
legend: true,
symbols: ["human", "heart", "fist", "clover", "rocket", "plane"],
dodge: true,
svg_margin: 20,
leg_type: "horizontal",
leg_pos: [400, 350],
leg_symbol_spacing: 40
})
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