roamHelper.js
1.67 KB
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define(function (require) {
var roamHelper = {};
/**
* @param {module:echarts/coord/View} view
* @param {Object} payload
* @param {Object} [zoomLimit]
*/
roamHelper.updateCenterAndZoom = function (
view, payload, zoomLimit
) {
var previousZoom = view.getZoom();
var center = view.getCenter();
var zoom = payload.zoom;
var point = view.dataToPoint(center);
if (payload.dx != null && payload.dy != null) {
point[0] -= payload.dx;
point[1] -= payload.dy;
var center = view.pointToData(point);
view.setCenter(center);
}
if (zoom != null) {
if (zoomLimit) {
var zoomMin = zoomLimit.min || 0;
var zoomMax = zoomLimit.max || Infinity;
zoom = Math.max(
Math.min(previousZoom * zoom, zoomMax),
zoomMin
) / previousZoom;
}
// Zoom on given point(originX, originY)
view.scale[0] *= zoom;
view.scale[1] *= zoom;
var position = view.position;
var fixX = (payload.originX - position[0]) * (zoom - 1);
var fixY = (payload.originY - position[1]) * (zoom - 1);
position[0] -= fixX;
position[1] -= fixY;
view.updateTransform();
// Get the new center
var center = view.pointToData(point);
view.setCenter(center);
view.setZoom(zoom * previousZoom);
}
return {
center: view.getCenter(),
zoom: view.getZoom()
};
};
return roamHelper;
});