Namespace: Globe3D

Globe3D

A globe: a camera and a body, inheriting from `view3d`. Nothing is projected — the geometry stays on the sphere and the horizon does the clipping. Created with `board.create('globe3d', [corner, size], attributes)`.
Source:

Members

scaleTo

Animated change of scale. Cheaper than the projection morph and needing none of its bookkeeping: every layer multiplies by scaleNow() while it draws, so nothing has to be rebuilt, no point counts have to match, and layers above the surface follow by themselves because their factor is relative.
Source:

Methods

addGeoLayer(kind, source, styleopt, orientsopt) → {Object}

A layer of your own geometry, clipped against the horizon like the others.
Parameters:
Name Type Attributes Description
kind string "rings" for filled shapes, anything else for lines.
source function Yields the geometry, as rings or polylines of [lon, lat] in degrees. Read again on every refresh.
style Object <optional>
 Curve attributes. Settings made once on the globe — `tabindex` above all — reach it too, and this overrides them.
orients function <optional>
 The winding of each ring, +1 or -1. Read on the sphere: the planar shoelace misreads a ring at a pole or across the antimeridian, and this value is used as given.
Source:
Returns:
The layer: `refresh()` and `setVisible(on)`.
Type
Object

at(bx, by) → (nullable) {Array.<number>}

Screen point to geographic position, or null beside the globe.
Parameters:
Name Type Description
bx number Board x.
by number Board y.
Source:
Returns:
[lon, lat] in degrees, or null where the point misses the sphere.
Type
Array.<number>

centre() → {Array.<number>}

Where the camera is looking.
Source:
Returns:
[lon, lat] in degrees, read back out of the rotation matrix.
Type
Array.<number>

clearSelection() → {Object}

Empty the selection. Announces once, and only if it was not empty.
Source:
Returns:
The globe, for chaining.
Type
Object

clipState() → {null}

Present so a host can be asked the same question as a map. A sphere has no strip to clip against — the horizon does that work — so there is no shared state to hand out.
Source:
Returns:
Always.
Type
null

deselect(id) → {Object}

Take a country out of the selection. Deselecting what is not selected changes nothing and announces nothing.
Parameters:
Name Type Description
id string A country id.
Source:
Returns:
The globe, for chaining.
Type
Object

destroy() → {Object}

Take the globe off the board. Listeners outlive the element that installed them: four globes left twenty of them behind, each answering every pointer move for something nobody is looking at. A board that cannot take a listener back is why the guard above exists as well.
Source:
Returns:
The globe, for chaining.
Type
Object

fromGeo(lon, lat) → {Object}

Geographic position to screen; `front` says whether it faces us.
Parameters:
Name Type Description
lon number Longitude in degrees.
lat number Latitude in degrees.
Source:
Returns:
Board position, and whether the point faces the camera.
Type
Object

geoPoint3D(lonFn, latFn, styleopt) → {Object}

A JSXGraph point3d that sits on the sphere and follows two functions. Useful where something else decides where it should be — a slider, a clock, an animation — and the point is to be dragged or measured with the rest of the 3D scene.
Parameters:
Name Type Attributes Description
lonFn function Yields the longitude in degrees.
latFn function Yields the latitude in degrees.
style Object <optional>
 Attributes for the point3d.
Source:
Returns:
The point3d.
Type
Object

lookAt(lon, lat) → {Object}

The only supported way to aim the camera. Slider.setValue clamps hard, and updateAngleSliderBounds() picks different ranges depending on the trackball: azimuth always [0, 2pi], elevation [-pi/2, pi/2] with the trackball and [0, 2pi] without. A raw setView latches at 90 degrees east, or anywhere in the southern hemisphere.
Parameters:
Name Type Description
lon number Longitude to face, in degrees.
lat number Latitude, held just short of the poles.
Source:
Returns:
The globe, for chaining.
Type
Object

pixelRadius()

Screen radius of the sphere in pixels. Everything drawn on or above it derives its sampling from this, so the resolution follows the size on screen instead of a fixed count.
Source:

rotateMode(mode) → {Object}

How the pointer may turn the globe.
Parameters:
Name Type Description
mode string 'free' for the trackball, 'azimuth' for spinning about the axis only, 'none' to fix it.
Source:
Returns:
The globe, for chaining.
Type
Object

select(id) → {Object}

Add a country to the selection. A tap goes through this same method, so both routes agree about what `selectMode` means: 'single' replaces, 'multiple' accumulates. The map had all three of the faults below, and so did this.
Parameters:
Name Type Description
id string A country id from the dataset.
Source:
Returns:
The globe, for chaining.
Type
Object

selectMode() → {string}

The selection mode in force.
Source:
Returns:
'none', 'single' or 'multiple'.
Type
string

selected() → {Array.<string>}

The current selection.
Source:
Returns:
Country ids, in the order they were added.
Type
Array.<string>

setClickTolerance(px) → {Object}

How far the pointer may travel between press and release and still count as a tap rather than a turn of the globe.
Parameters:
Name Type Description
px number Distance in pixels.
Source:
Returns:
The globe, for chaining.
Type
Object

setHoverCountries(on) → {Object}

Whether moving the pointer sends countryover and countryout.
Parameters:
Name Type Description
on boolean Whether to report hovering.
Source:
Returns:
The globe, for chaining.
Type
Object

setLayer(name, on) → {Object}

Switch a layer on or off.
Parameters:
Name Type Description
name string A layer name: land, farSide, coast, countries, capitals, graticule, or one returned by addGeoLayer.
on boolean Whether to draw it.
Source:
Returns:
The globe, for chaining.
Type
Object

setPicking(on) → {Object}

Whether a tap looks up which country was hit at all. With it off the globe still reports geoclick, but neither countryclick nor the selection.
Parameters:
Name Type Description
on boolean Whether to identify countries.
Source:
Returns:
The globe, for chaining.
Type
Object

setScale(f) → {Object}

Shrink the Earth so a whole orbit fits inside the world cube.
Parameters:
Name Type Description
f number The new radius in world units. Zero or less is refused: negative mirrors the body through the centre and leaves `at` answering null everywhere.
Source:
Returns:
The globe, for chaining.
Type
Object

setSelectMode(mode) → {Object}

How a tap builds a selection: 'none', 'single' or 'multiple'.
Parameters:
Name Type Description
mode string One of the three; anything else warns and is ignored.
Source:
Returns:
The globe, for chaining.
Type
Object

setSelection(ids) → {Object}

Replace the whole selection at once.
Parameters:
Name Type Description
ids Array.<string> Country ids. Unknown ones are refused, and under `selectMode: single` the last one named wins.
Source:
Returns:
The globe, for chaining.
Type
Object

setSmallCountries(on) → {Object}

Whether the 29 countries with no outline are drawn as stand-in circles.
Parameters:
Name Type Description
on boolean Whether to draw them.
Source:
Returns:
The globe, for chaining.
Type
Object

setTrackballReset(on) → {Object}

Whether the stored pointer delta is cleared on every board update. updateProjectionTrackball re-applies that delta each time, so an extra update from an unrelated handler turns the globe again — several times per pointer move, and between two layer updates within one frame.
Parameters:
Name Type Description
on boolean Whether to clear it.
Source:
Returns:
The globe, for chaining.
Type
Object

showDistortion(mode) → {Object}

Show what a projection does to shape and size — on the globe, where it does nothing, which is the point of drawing it here as well.
Parameters:
Name Type Description
mode string 'tissot' or 'none'.
Source:
Returns:
The globe, for chaining.
Type
Object

showFeatures(list) → {Object}

Draw a set of named features: equator, tropics, polar circles, the prime meridian, the date line, the nominal time zones, the terminator. They replace whatever was shown before, so an empty list clears them.
Parameters:
Name Type Description
list Array.<string> Keys of `G.features`.
Source:
Returns:
The globe, for chaining.
Type
Object

spin(speedopt) → {Object}

Turn the globe by itself, about its axis.
Parameters:
Name Type Attributes Default Description
speed number <optional>
 0.0045 Radians per frame; negative turns the other way.
Source:
Returns:
The globe, for chaining. A running spin is stopped first, and without a frame timer nothing is started.
Type
Object

stop() → {Object}

Stop a spin, leaving the globe where it is.
Source:
Returns:
The globe, for chaining.
Type
Object

stopScale() → {Object}

Cut a running scale animation short, leaving the radius where it is.
Source:
Returns:
The globe, for chaining.
Type
Object

tapState() → {Object}

What the tap detector has seen: counts of down, move and up, whether it is reading pointer events or board events, and how far the last gesture travelled. For diagnosis. On touch devices the board's own 'up' carries no coordinates at all, which is why there are two paths to begin with.
Source:
Returns:
A live view of the counters.
Type
Object

trackballState() → {Object}

What the trackball is doing: the board mode, whether a move handler is installed, whether the reset above is on, and the stored delta. For diagnosis. A globe that turns twice per gesture, or not at all, is hard to investigate from the outside.
Source:
Returns:
A snapshot of those five values.
Type
Object