/
getContourHolesDataCanvas.ts
33 lines (27 loc) · 1.14 KB
/
getContourHolesDataCanvas.ts
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import type { Types } from '@cornerstonejs/core';
import type { Annotation } from '../../types';
import getContourHolesDataWorld from './getContourHolesDataWorld';
/**
* Get the polylines for the child annotations (holes)
* @param annotation - Annotation
* @param viewport - Viewport used to convert the points from world to canvas space
* @returns An array that contains all child polylines
*/
export default function getContourHolesDataCanvas(
annotation: Annotation,
viewport: Types.IViewport
): Types.Point2[][] {
const worldHoleContours = getContourHolesDataWorld(annotation);
const canvasHoleContours = [];
worldHoleContours.forEach((worldHoleContour) => {
const numPoints = worldHoleContour.length;
// Pre-allocated arrays are 3-4x faster than multiple "push()" calls
const canvasHoleContour: Types.Point2[] = new Array(numPoints);
// Using FOR loop instead of map() for better performance when processing large arrays
for (let i = 0; i < numPoints; i++) {
canvasHoleContour[i] = viewport.worldToCanvas(worldHoleContour[i]);
}
canvasHoleContours.push(canvasHoleContour);
});
return canvasHoleContours;
}