Let's continue on the quick guide of using Google Map API.
Using Custom Icons
The hardest part is creating graphics for your marker image and its shadow with Photoshop or something. The icons should be cretaed in 24-bit png format. For this example, I just tweaked the default icon (the color changed to blue, made it bigger, and typed "SFO" in it!) and used default shadow.
To replace the generic icon to your custom icon, add this code in the last script, before the line that begins with var marker = ...
var icon = new GIcon(); icon.image = "icons/sfo.png"; icon.shadow = "http://www.google.com/mapfiles/shadow50.png"; icon.iconSize = new GSize(26, 44); icon.shadowSize = new GSize(50, 44); icon.iconAnchor = new GPoint(13, 44);
First, create a new icon instance (line 1).
Next two lines indicate icon/shadow image source path or URL. (I use default shadow image on Google server).
Next two specifies the image dimention in pixels.
Anchor point of the icon is the "pointy" tip where also its shadow image originates. In this case, the anchor point is 13 pixels over and 44 pixels down from the top-left corner of the SFO icon, and this is defined by iconAnchor (line 6).
Location of the marker is defined by GMarker, just as you see in the last example, except, this time you need to add the 2nd paramter to include the custom icon. Finally, call addOverlay() method to dispaly thr marker icon.
var marker = new GMarker(new GLatLng(37.622934, -122.392159), icon); map.addOverlay(marker);
Next: Opening an Info Window