topic Re: SimpleFillSymbol alpha value producing different color across multiple polygons in ArcGIS JavaScript Maps SDK Questions

SimpleFillSymbol alpha value producing different color across multiple polygons

AndrewRousseau — Thu, 12 Jan 2017 18:38:55 GMT

All of the polygons below are produced with the same color settings with 125 as the alpha value,

but you can see the result is different in each polygon.

Any way to get a consistent color with the same opacity in each? I did double check and I'm pretty sure none of the polygons overlap.

Re: SimpleFillSymbol alpha value producing different color across multiple polygons

RobertScheitlin__GISP — Thu, 12 Jan 2017 18:55:11 GMT

Andrew,

Are any of the polygons duplicated in the json?

Re: SimpleFillSymbol alpha value producing different color across multiple polygons

KristianEkenes — Thu, 12 Jan 2017 19:00:13 GMT

Which API version are you using?

Re: SimpleFillSymbol alpha value producing different color across multiple polygons

AndrewRousseau — Thu, 12 Jan 2017 19:27:32 GMT

No duplicates, just double checked.

Re: SimpleFillSymbol alpha value producing different color across multiple polygons

AndrewRousseau — Thu, 12 Jan 2017 19:27:40 GMT

https://js.arcgis.com/3.18/"

Re: SimpleFillSymbol alpha value producing different color across multiple polygons

KristianEkenes — Thu, 12 Jan 2017 19:39:43 GMT

I'm not able to independently verify this in a simple test app. I would need to see a sample with more of your code in context. Are you able to share this in jsbin or some other way?

Re: SimpleFillSymbol alpha value producing different color across multiple polygons

TomSellsted — Thu, 12 Jan 2017 19:53:49 GMT

Andrew,

The range for alpha should be a value from 0 to 1. Maybe that is creating your inconsistency?

Regards,

Tom

Re: SimpleFillSymbol alpha value producing different color across multiple polygons

KristianEkenes — Thu, 12 Jan 2017 19:57:30 GMT

When loading a symbol from JSON the range is 0-255.

See ArcGIS REST API.

Re: SimpleFillSymbol alpha value producing different color across multiple polygons

AndrewRousseau — Thu, 12 Jan 2017 20:43:55 GMT

I figured it out. I was looping through the array of shapes from my database and conditionally only showing some of them based on filters on the page. However, I neglected to include the "map.graphics.add(new Graphic(poly, sym));" call inside the condition so it was adding empty Graphic entries which for some reason was causing the color inconsistencies. Thanks to @Kristian Ekenes as I discovered this in trying to create a sample of the code to post for debugging. Thanks to everyone for your input, hopefully this post will help someone else debug this issue in the future if they make the same mistake!