topic Re: Are the circle and scalebar dependent on each other? in GIS Life Discussions

Are the circle and scalebar dependent on each other?

QuangLinh — Tue, 23 Jul 2024 10:43:37 GMT

Hi everybody
When I enter a radius of 500km when drawing on the map the diameter of the circle will be 1000km and will be equal to the scalebar line in the lower right corner. But the problem is that when I draw on the map, the circle is smaller than the scalebar in the lower right corner. And I want to confirm that circle and scalebar are dependent on each other? If so, how can the drawn circle be equal to the line of the scalebar in the lower right corner? On the contrary, if they are not dependent on each other, please give me a link to prove it. Thank you

Re: Are the circle and scalebar dependent on each other?

BobBooth1 — Tue, 23 Jul 2024 18:45:16 GMT

Check out these resources.

https://mediaspace.esri.com/media/t/1_b75ular2

https://learn.arcgis.com/en/paths/map-projections/

Re: Are the circle and scalebar dependent on each other?

Faiez — Tue, 06 Aug 2024 06:34:53 GMT

Hi!

As Bob has mentioned, it is very important to select the right GCS and PCS for your map and layers. GCS defines the location of data on the earth's surface while the PCS draw the data on a flat surface. If you want to create a concentric ring and display it on the google earth here is the option:

1. Open the project> in case of need you can add a layer> otherwise just use the map.

2. Cliks Insert>Distance and Direction tab on thr ribbon> select ring>

3. Fill the table

4. click create. if you want to display it on the google earth export it as a KML.

(view in My Videos)

Re: Are the circle and scalebar dependent on each other?

nhanvi — Fri, 02 Aug 2024 01:34:26 GMT

Hello, @Faiez Do you know how to implement it via Javascript API? I had the same issue. my map uses WGS 1984 Web Mercator whenever I draw a ring the ring is slightly smaller than the scalebar.

Re: Are the circle and scalebar dependent on each other?

Faiez — Sat, 03 Aug 2024 12:11:05 GMT

Hello!

<!DOCTYPE html>

<html>

<body>

<h1>Circle </h1>

</canvas>

const canvas = document.getElementById("myCanvas");

const ctx = canvas.getContext("2d");

ctx.beginPath();

ctx.arc(95,50,40,0,2*Math.PI);

ctx.stroke();

</script>

</body>

</html>

<!DOCTYPE html>

<html>

<head>

<style>

.dot {

height: 100px;

width: 100px;

background-color: #6de992;

border-radius: 100%;

display: inline-block;

}

</style>

</head>

<body>

<h1>Circle</h1>

</div>

</body>

</html>

3. https://www.mapdevelopers.com/draw-circle-tool.php?circles=%5B%5B500000%2C59.3251172%2C18.0710935%2C%22%23AAAAAA%22%2C%22%23000000%22%2C0.4%5D%5D

When a marker or a circle icon addet to the map, it is associated with the map.

Good luck,

Faiez