To make an Overlay Map, you’ll need an image file (usually a png) that will be your map. There are some important requirements and things to know about this image.
Typically, the image file used for a custom maps will:
- Be less than about 2 or 3 megabytes in filesize
- Be less than about 4000px in the longest dimension
- Be in png format with a transparent background
- Have no text or icons incorporated (these will be added in with dynamically resizing ones later)
These are not hard and fast rules, but are good rules of thumb, and care should be taken when choosing to go outside of those guidelines. For details and explanations, see here: https://www.mapiddiction.com/knowledge_base/image-requirements-for-an-overlay-on-base-maps/
For this demo, I’ll use an image file like this. It’s transparent background png image (the grey checkerboard shown here is the transparent part of the real image):
Once you have your image file, here’s how to use it in Mapiddiction.
Log in to your Mapiddiction account from using the link in the top right corner of www.mapiddiction.com. (If you don’t have an account yet, see here)
Once logged in, you will start at the dashboard.
Click the Add New button
Choose Overlay Map (To learn about the three different map types, click here), then click Next:
Select what type of map you’re building. This choice sets up a set default icons of marker pins that will be available – you can always update these later. If you’re not sure, choose Custom. If you’re just experimenting to learn howe Mapiddiction works, choose one of the others, like Theme Park, as that will show you some of the capabilities of Marker Types without you needing toi set them up manually. Here we’ll choose Theme Park, and click Next:
Add a Name and Description for your map, and (optionally) upload a thumbnail.
The Thumbnail image will be displayed at around 200×200 pixels, so the thumbnail image should be around that size, and under a hundred kb or so. You upload the image by clicking Add Image(s) like this:
Click the Upload button, and file the file on your computer and upload it, then select it in the Recently Modified section:
Double check your details here, and click next
Choose your Marker Types. These are the icons used to Marker Pins on the map. You can see here the selected Theme Park icons from earlier already added.
You can add additional Marker Types here, choosing from many inbuilt icons or uploading you own custom icons:
For this demo, we’ll just stick with the Theme Park icon set, and click Next, then check all your information before clicking Create Map. It will take a few moments to create your map.
Next you need to set the map location:
You can type in an address, or minimise that dialog box and pan and zoom around the map:
Pan and zoom until the region of the map your image will cover fills the map window, without chopping off any parts – then click Set Area
Now you add your overlay image. Click the Add Your First Overlay button here:
Upload and select your Overlay Image:
Align your image with the base map. You need to choose two points that you can identify accurately on both your Image Overlay and on the base map. You want points you can accurately locate on both the image and the base map, something like building corners or path intersections. The more accurately you can locate these two points on both the image and the base map, the better calibrated your final map will be. Try and choose points that are as far apart as practical, and that are diagonally opposite each other for best results.
Using the Full Screen alignment will work best for most people:
Zoom in and pan on your image to select the first and second alignment points. Here I’ve used a building corner and a path intersection.
Here are the two points zoomed out. Note they are diagonally apart, and as far away from each other as practical:
Exit fullscreen and click Next in the left hand pane:
You can choose to align using street or satellite view – depending on which allows better accuracy selecting the points. I’ll choose Satellite view for the building corner, then switch back to street view for the path intersection point:
Here I’m selecting the same building corner on the satellite view as I chose on the image:
Here I’m using the street view, because it’s easier to accurately align the path intersection I chose on the image:
You may need to scroll down a little in the left pane too get to the Apply Alignment button:
Use the Overlay Settings menu to check how well your image is aligned. You cab adjust the Overlay Opacity, then zoom in close to compare your image and the base map. You can see here the paths are perfectly aligned in some places, and misaligned by a meter or two in other places. This is due to inaccuracy of the image I started with, but is close enough to be usable here:
Your Image Map is now aligned, you can now add Markers, Labels, and Shapes over your map:
