ducjs/dist/technical/measurements.js

The duc 2D CAD file format is a cornerstone of our advanced design system, conceived to cater to professionals seeking precision and efficiency in their design work.

import { calculateScope, getTranslationFactor } from "./scopes";
/**
 * Gets translation factor between current scope and element scope
 */
export function getElementTranslationFactor(currentScope, elementScope) {
    return getTranslationFactor(elementScope, currentScope);
}
/**
 * Gets the appropriate unit for the current zoom level
 *
 * @param zoom - Current zoom level
 * @param mainMeasure - Main/base measurement unit
 * @param scopeExpThreshold - Controls the sensitivity of precision scope changes
 * @returns The most appropriate measurement unit for the current zoom
 */
export function getPrecisionScope(zoom, mainMeasure, scopeExpThreshold) {
    return calculateScope(zoom, scopeExpThreshold, mainMeasure);
}
export const coordinateToRealMeasure = (coordinate, currentScope, elementScope) => {
    const translationFactor = getElementTranslationFactor(currentScope, elementScope);
    // 100 grid units is 1,00 real unit
    return coordinate * translationFactor / 100;
};
export const realMeasureToCoordinate = (realMeasure, gridUnit) => {
    // x grid units * 100 = 1,00 real unit
    return realMeasure * 10 * gridUnit;
};
export function filterElementsByScope(elements, currentScope) {
    return elements.filter((element) => element.scope === currentScope);
}
/**
 * Calculates the approximate size of a single physical device pixel in millimeters.
 *
 * This calculation is based on the standard CSS definition of a reference pixel
 * (1/96th of an inch) and the current devicePixelRatio of the window.
 *
 * It reflects the effective size of the smallest addressable pixel by the browser,
 * considering screen density and browser/OS zoom levels.
 *
 * @returns {number} The approximate size of a physical pixel in millimeters.
 * Returns NaN if window or window.devicePixelRatio is not available (e.g., in a Node.js environment).
 */
export const getPhysicalDevicePixelSizeInMm = () => {
    // Check if running in a browser environment where window and devicePixelRatio are available
    if (typeof window === 'undefined' || typeof window.devicePixelRatio === 'undefined') {
        console.warn('window.devicePixelRatio is not available. This function should be run in a browser environment.');
        return NaN; // Not applicable or calculable outside a browser context
    }
    // Standard conversion: 1 inch = 25.4 millimeters
    const mmPerInch = 25.4;
    // Standard CSS pixels per inch (W3C reference pixel definition)
    const cssPixelsPerInch = 96;
    // Calculate the conceptual size of one CSS pixel in millimeters.
    // This is the physical size a CSS pixel would ideally occupy if devicePixelRatio were 1.
    const cssPixelSizeInMm = mmPerInch / cssPixelsPerInch;
    // Get the current device pixel ratio from the window.
    // This value accounts for the screen's native density and any browser or OS zoom applied.
    const currentDevicePixelRatio = window.devicePixelRatio;
    // The size of a single physical pixel is the conceptual size of a CSS pixel
    // divided by the devicePixelRatio. This is because devicePixelRatio indicates
    // how many physical pixels are used to render one CSS pixel in each dimension.
    const physicalPixelSizeInMm = cssPixelSizeInMm / currentDevicePixelRatio;
    return physicalPixelSizeInMm;
};