Map canvases use a marker symbol option

[alexgao1]

The OpenLayers 2 canvas should be able to display a marker using a custom PNG or SVG icon.
See:

• https://github.com/openlayers/ol2/blob/master/examples/markers.html
• https://github.com/openlayers/ol2/blob/master/examples/markersTextLayer.html
• https://github.com/openlayers/ol2/blob/master/examples/markerResize.html
• https://github.com/openlayers/ol2/blob/master/examples/marker-shadow.html
• https://web.archive.org/web/20200711225807/http://dev.openlayers.org/releases/OpenLayers-2.13.1/doc/apidocs/files/OpenLayers/Marker-js.html

It should be configurable like the usual symbol configuration for maps.

Addtionally, this should also work for the newer OpenLayers 6 canvas, although the code for that may be quite different.

https://openlayers.org/en/latest/examples/icon.html