@cesium/engine/Source/Core/resizeImageToNextPowerOfTwo.js

CesiumJS is a JavaScript library for creating 3D globes and 2D maps in a web browser without a plugin.

import CesiumMath from "./Math.js";

/**
 * Resizes an image to ensure both width and height are powers of 2.
 * NOTE: The input image is resampled larger, rather than padded.
 * The aspect ratio of the image may change.
 *
 * @param {HTMLImageElement|HTMLCanvasElement} image The image to be resized
 * @returns {HTMLCanvasElement} A new canvas with the resized image drawn to it
 *
 * @private
 */
function resizeImageToNextPowerOfTwo(image) {
  const canvas = document.createElement("canvas");
  canvas.width = CesiumMath.nextPowerOfTwo(image.width);
  canvas.height = CesiumMath.nextPowerOfTwo(image.height);
  const canvasContext = canvas.getContext("2d");
  canvasContext.drawImage(
    image,
    0,
    0,
    image.width,
    image.height,
    0,
    0,
    canvas.width,
    canvas.height,
  );
  return canvas;
}
export default resizeImageToNextPowerOfTwo;