New module proposal: Transform

Inspired by PR #729 and the necessity to use a rotated gridPoint as turf-isobands input, I’d like to implement the following basic transformation functions, if of interest in Turf:

@turf/transform-translate

• Moves a feature of distance kilometers (or units) on a specific direction angle
• 3rd (z) coordinates support

/**
@param {GeoJSON}` **object** to be translated
@param {Number}` **distance** length of the motion
@param {Number}` **direction** angle/bearing of the motion, in degrees from North (positive clockwise)
@param {String}` **units** (optional, default Km) unit for distance
@returns {Feature<any>}` the translated Feature

@turf/transform-scale

• Enlarges or shrinks a feature by a scale factor.
• 3rd (z) coordinates support

/**
@param {GeoJSON}` **object** to be scaled
@param {Number}` **factor** scale factor (positive number)
@param {Feature|Geometry<Point>|Array<number>}` **origin** point (of the Feature) around which the scaling will occur, defaults to centroid
@returns {Feature<any>}` the scaled Feature

@turf/transform-rotate

• Rotates a feature of angle degrees around a fixed point (default to its center/center of mass/centroid)
• 3rd (z) coordinates support (rotation only by z axis, i.e. on the x,y plane)

/**
@param {GeoJSON}` **object** to be rotated
@param {Number}` **angle** extent of the rotation, in degrees from North (positive clockwise)
@param {Feature|Geometry<Point>|Array<number>}` **pivot**, point around which the rotation will occur, defaults to `centroid`
@returns {Feature<any>}` the rotated Feature

Geometry Support

• Geometry|Feature<Point> => Feature<Point>
• Geometry|Feature<LineString> => Feature<LineString>
• Geometry|Feature<Polygon> => Feature<Polygon>
• Geometry|Feature<MultiPoint> => Feature<MultiPoint>
• Geometry|Feature<MultiLineString> => Feature<MultiLineString>
• Geometry|Feature<MultiPolygon> => Feature<MultiPolygon>

[DenisCarriere]

Woot 🎉 https://github.com/Turfjs/turf/pull/759

[DenisCarriere]

My 👍 votes for the following:

• 3 coordinates support (on initial draft don’t worry about it too much, as long as the 3rd coordinate isn’t dropped)
• having 3 separate modules for this proposal (initial names defined by @stebogit, @turf/transform-rotate, @turf/transform-translate, @turf/transform-scale)
• pivot param name for @turf/transform-rotate
• origin param for `@turf/transform-scale