IITC plugin: Extra zoom: Load portals/links from higher zoom levels (click statusbar) [https://gist.github.com/johnd0e/fcfd9d365a9a4714b8f93ac0afb81b25/raw/extra-zoom.user.js]

extra-zoom.meta.js

// ==UserScript==
// @id             iitc-plugin-extra-zoom
// @name           IITC plugin: Extra zoom
// @description    Load portals/links from higher zoom levels (click statusbar)
//                 Increases data zoom, in steps (limit: 4 levels)
// @category       Info
// @version        0.3.3
// @author         jd
// @namespace      https://gist.github.com/johnd0e
// @homepageURL    https://gist.github.com/johnd0e/fcfd9d365a9a4714b8f93ac0afb81b25
// @supportURL     https://gist.github.com/johnd0e/fcfd9d365a9a4714b8f93ac0afb81b25#new_comment_field
// @updateURL      https://gist.github.com/johnd0e/fcfd9d365a9a4714b8f93ac0afb81b25/raw/extra-zoom.meta.js
// @downloadURL    https://gist.github.com/johnd0e/fcfd9d365a9a4714b8f93ac0afb81b25/raw/extra-zoom.user.js
// @include        https://intel.ingress.com/intel*
// @grant          none
// ==/UserScript==

extra-zoom.user.js

// ==UserScript==
// @id             iitc-plugin-extra-zoom
// @name           IITC plugin: Extra zoom
// @description    Load portals/links from higher zoom levels (click statusbar)
//                 Increases data zoom, in steps (limit: 4 levels)
// @category       Info
// @version        0.3.3
// @author         jd
// @namespace      https://gist.github.com/johnd0e
// @homepageURL    https://gist.github.com/johnd0e/fcfd9d365a9a4714b8f93ac0afb81b25
// @supportURL     https://gist.github.com/johnd0e/fcfd9d365a9a4714b8f93ac0afb81b25#new_comment_field
// @updateURL      https://gist.github.com/johnd0e/fcfd9d365a9a4714b8f93ac0afb81b25/raw/extra-zoom.meta.js
// @downloadURL    https://gist.github.com/johnd0e/fcfd9d365a9a4714b8f93ac0afb81b25/raw/extra-zoom.user.js
// @include        https://intel.ingress.com/intel*
// @grant          none
// ==/UserScript==


function wrapper(plugin_info) {
// ensure plugin framework is there, even if iitc is not yet loaded
if(typeof window.plugin !== 'function') window.plugin = function() {};



// PLUGIN START ////////////////////////////////////////////////////////

// inspired by https://github.com/3ch01c/iitc-plugins/blob/master/superdata.user.js

// use own namespace for plugin
// window.plugin.extraZoom = function() {};

const MAX_ZOOM_DIFF = 4;        // resonable limit
const ZOOM_DEFAULT = undefined; // any false value

let extraZoom = ZOOM_DEFAULT;   // 'virtual' data zoom value

let style; // to be changed in order to indicate overriden zoom state

let getDataZoom; // to store original window.getDataZoomForMapZoom

function set_zoom (value) {
  extraZoom = value;
  window.renderUpdateStatus();
  style.text(value ? '#loadlevel { color: red }' : '');
}

function next_step () {
  const zoom = window.map.getZoom();
  const last = extraZoom || zoom;
  const max = zoom + MAX_ZOOM_DIFF;
  for (let z=last; z<=max; z++) {
    if (getDataZoom(z) > last) {
      return z;
    }
  }
}

function toggle () {
  const z = next_step();
  if (z) {
    set_zoom(z);
    window.mapDataRequest.start();
  } else if (extraZoom) {
    set_zoom(ZOOM_DEFAULT);
  }
}

function setup () {
  $('#innerstatus').click(toggle);

  style = $('<style>').prop('type', 'text/css').appendTo('head')

  getDataZoom = window.getDataZoomForMapZoom;
  window.getDataZoomForMapZoom = function (zoom) {
    return extraZoom || getDataZoom(zoom);
  };

  let prev;
  window.map.on('zoomstart zoomend',function(e) {
    // https://leafletjs.com/reference-1.3.4.html#map-zoomend
    if (extraZoom) {
      const zoom = e.target.getZoom();
      switch(e.type) {
        case 'zoomstart':
          // experimental: to not switch back if data zoom stays the same
          prev = getDataZoom(zoom);
          break;
        case 'zoomend':
          if (zoom < prev || zoom >= extraZoom) {
            set_zoom(ZOOM_DEFAULT); // switch back to default view when zooming out
          }
      }
    }
  });
}

// PLUGIN END //////////////////////////////////////////////////////////


setup.info = plugin_info; //add the script info data to the function as a property
if(!window.bootPlugins) window.bootPlugins = [];
window.bootPlugins.push(setup);
// if IITC has already booted, immediately run the 'setup' function
if(window.iitcLoaded && typeof setup === 'function') setup();
} // wrapper end
// inject code into site context
var script = document.createElement('script');
var info = {};
if (typeof GM_info !== 'undefined' && GM_info && GM_info.script) info.script = { version: GM_info.script.version, name: GM_info.script.name, description: GM_info.script.description };
script.appendChild(document.createTextNode('('+ wrapper +')('+JSON.stringify(info)+');'));
(document.body || document.head || document.documentElement).appendChild(script);