rogram(program);
gl.uniformMatrix4fv(matrixLoc, false, mat);

const numVertices = (gridWidth * 2 * (gridDepth + 1)) +
                    (gridDepth * 2 * (gridWidth + 1));
gl.drawElements(
    gl.LINES,           // primitive type
    numVertices,        //
    gl.UNSIGNED_SHORT,  // type of indices
    0,                  // offset
);



</script>
