44 lines
1009 B
JavaScript
44 lines
1009 B
JavaScript
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/**
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* A projection determines how a geographical card has to
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* be interpreted to map coordinate to pixels.
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*
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* Most used transformation is the mercator projection,
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* which projects a sphere on a cylinder.
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*
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* @abstract
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*/
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export default class Projection {
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/**
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* Transforms a coordinate to a normalized position on the map.
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*
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* @param {*} coords
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* @memberof Projection
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*/
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forward(coords) {
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console.error('You must override the forward function in ' + this.name + '.')
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}
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/**
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* Transforms a normalized point on the map to a coordinate.
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*
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* @param {*} point
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* @memberof Projection
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*/
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backward(point) {
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console.error('You must override the backward fuction in ' + this.name + '.')
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}
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toString() {
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return 'Projection (abstract)'
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}
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get name() {
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return this.toString()
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}
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get maxViewport() {
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return { min: new PIXI.Point(-90, -180), max: new PIXI.Point(90, 180) }
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}
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}
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