main();

​

//

// start here

//

function main() {

  const canvas = document.querySelector("#glcanvas");

  // Initialize the GL context

  const gl = canvas.getContext("webgl");

​

  // Only continue if WebGL is available and working

  if (gl === null) {

    alert(

      "Unable to initialize WebGL. Your browser or machine may not support it.",

    );

    return;

  }

​

  // Set clear color to black, fully opaque

  gl.clearColor(0.0, 0.0, 0.0, 1.0);

  // Clear the color buffer with specified clear color

  gl.clear(gl.COLOR_BUFFER_BIT);

}