Slow load times on maps with many markers and polygons

Jake Huddleston's Avatar

Jake Huddleston

12 May, 2020 05:14 AM

I am having very slow load times with a map that has many markers and polygons. I'm talking thousands of markers and perhaps a few hundred polygons throughout Washington state. Zooming and dragging the map takes a very long time to load. I often have to disable markers in order to move around more efficiently. This doesn't happen with any other map with only a handful of objects, so I just assume that maps with many objects simply need more time to load due to all the data points. Layers don't seem to be an issue, only the number of objects on the map.

First question, is this normal? And second question, how might I go about mitigating this issue? Is it possible to highlight an area and export all the objects in that area? That way I could create several new maps separated by regions and hopefully speed things up. Thanks!

  1. Support Staff 1 Posted by Julie on 12 May, 2020 03:01 PM

    Julie's Avatar

    Hello Jake,

    Huge maps and data sets do take longer to load and to work with. A couple of things that especially affect the time required are
    1. Special line types (dotted, dashed, etc.)
    2. Labels. These can be turned off in the Config menu at the top of the browser window.

    We do recommend that you separate the data into smaller maps. You will use the export menu to do this, also located at the top of the browser window. There are a few ways to go about this. First, if you haven't already, before you get started it will help you much to make sure all your objects have some clear labeling system so that you can identify them from a list and not just visually on the map.

    Then you can go to "Export" then at the bottom under CalTopo "Copy to a New Map". A window will appear that allows you to select the objects that you want to copy to the new map. Select the ones that you want for the new region, then Export. A new browser tab will open with the new map and the objects that you selected for it.

    After you have created your new regional maps, if you want to delete objects from the original map, use "Bulk Ops" to delete multiple items at once. You will find Bulk Ops at the bottom of any folder in the left hand side panel of the browser screen. Click it to open the Bulk Ops options window, multi-select the objects that you want to delete, then click "delete objects" at the bottom.


  2. Julie closed this discussion on 12 May, 2020 03:01 PM.

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