ol-ext: Image line control

The ol/control/Imageline displays images on map as a line. You can navigation no the line.

• You have to define a ol/vector/source that contains the features with the image.
• The getImage option is a function that takes a feature and returns an image to display in the line.
• You can specify a title for the image using the getTitle option.
• Clicking on an image will trigger a select event you can catch to do something (center on the feature).
• You can display all images on a layer or only those visible in the current map extent.
• lineColor option let you display a link when a photo is selected, use false to remove the link.
• hover option will select the photo on hover