iwmlib/lib/pixi/maps/projections/projection.js

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/**
* A projection determines how a geographical card has to
* be interpreted to map coordinate to pixels.
*
* Most used transformation is the mercator projection,
* which projects a sphere on a cylinder.
*
* @abstract
*/
export default class Projection {
/**
* Transforms a coordinate to a normalized position on the map.
*
* @param {*} coords
* @memberof Projection
*/
forward(coords) {
console.error('You must override the forward function in ' + this.name + '.')
}
/**
* Transforms a normalized point on the map to a coordinate.
*
* @param {*} point
* @memberof Projection
*/
backward(point) {
console.error('You must override the backward function in ' + this.name + '.')
}
toString() {
return 'Projection (abstract)'
}
get name() {
return this.toString()
}
get maxViewport() {
return { min: new PIXI.Point(0, 0), max: new PIXI.Point(1, 1) }
}
}