function isEquirectangularMapReady$1( image ) {

	if ( image === null || image === undefined ) return false;

	return image.height > 0;

}
Returns true if the given equirectangular image has been fully loaded
and is ready for further processing.

@private
@param {Image} image - The equirectangular image to check.
@return {boolean} Whether the image is ready or not.