How do I determine current level, row, and column based on extent for a layer?

RobertWinterbottom — Thu, 23 Jun 2016 17:59:31 GMT

Hi,

Is there a relatively simple way to determine what the level, row , and column are for the current extent? I know level is easy, map.getLevel(), but I am not sure how to determine what the row's and column's are currently on the map so I can request the correct tiles. If I extend the TiledMapServiceLayer, I can use the getTileUrl function, but it renders images in a div and I need to render to a canvas element.

Just some background on what I am looking at doing. I have a html canvas element I would like to render images onto. These images are stood up in a s3 bucket in a tiled format( http://....../{z}/{x}/{y}.png). I have created a custom layer that places a canvas element on the map, but I would like to know which tile to request so I can add it to the canvas. I need to do some advanced filtering and read the image data from canvas so I cannot use a simple WebTiledLayer.

topic How do I determine current level, row, and column based on extent for a layer? in ArcGIS JavaScript Maps SDK Questions

How do I determine current level, row, and column based on extent for a layer?