Friday, February 8, 2008

Excel To Kml - Direction Arrows for GPS Track

ExcelToKml can draw direction arrows on a GPS track.  The column headings to look at are "IconHeading" and "IconColor".

The picture to the right shows an example of a GPS track.  Note that the arrows point in the direction of travel.  This track was plotted with the following spreadsheet values:

  A B C D E F
1 Latitude Longitude Icon IconHeading IconColor LineColor
2 43.6097 -116.2048 196 line -180 yellow aqua
3 43.6095 -116.2047 196 line -180 yellow aqua
4 43.6094 -116.2046 196 line -180 yellow aqua
5 43.6094 -116.2044 196 line -180 yellow aqua
6 43.6094 -116.2042 196 line -180 yellow aqua
7 43.6095 -116.2041 196 line -180 yellow aqua
8 43.6096 -116.2043 196 line -180 yellow aqua
9 43.6097 -116.2046 196 line -180 yellow aqua

This spreadsheet is included in the sample data.

The column IconHeading specifies how many degrees to rotate the icon.  IconHeading can be a number, the word "line", or the word "line" plus or minus a number.

For example, Icon 222 is Google's airplane icon. It looks like this on Google Earth.

If a value of 90 is entered into the IconHeading column, the icon is rotated 90 degrees to the right.

If a value of -90 is entered into the IconHeading column, the icon is rotated 90 degrees to the left.

If the word "line" is entered into the IconHeading column, the airplane is rotated to point in the direction of travel.  That is, the airplane looks like it is flying along the line.

If the value "line-180" is entered into the IconHeading column, the airplane is lined up with the direction of travel, then spun around 180 degrees.  The airplane looks like it is flying backwards.

"line-180" is quite useful when using Icon 196, Google's arrow icon.  Notice that by default the arrow points down, not up.  If we specified a value of "line" in the IconHeading column, the arrow would point in the wrong direction.

To fix this, use a value of "line-180" (or "line+180"), which flips the arrow around 180 degrees and points it in the right direction.

Another problem is that the arrow is hard to see because it is just an outline.  Use IconColor to add color to any icon.  Yellow looks like this:

This combination of IconHeading and IconColor gives us the GPS track illustrated at the beginning of this article.


helyair said...

Oh, great!
But, it's possible to draw a coloured surface with your utility among the points? Thanks

me said...

I just wanted to say thanks for the great resource. Your conversion utility and well
documented quick start guide helped me add a travel route for google map/earth
to my blog,

Bruce Berger said...

I need to draw 5 unconnected tracks across the globe. Each line is a different color. How can I do this?

Bill Clark said...

If I understand correctly, you want five separate lines drawn on the globe. If you have one interrupted list of lat/lon coordinates, it will be necessary to introduce a break in the data between each track.

Options, ranked from uninteresting to interesting...
1) You can put each track into separate spreadsheets.
2) You can put each track into a separate tab (worksheet) in the same workbook.
3) You can put all of the data into one worksheet, but put a blank line in between each track.
4) You can put all of the data into one worksheet, with no blank lines, but leave the linecolor blank for the last point of each track. That way, ExcelToKml will not connect that point to the next one.

Hope this helps. Please let me know.

Unknown said...

Can I draw seprate traks from a central point to all other location ???

Bill Clark said...

They can be drawn as separate lines, all starting at the same point. An example is available at

Unknown said...

I can not get my Icon so show up in my kml files. I have the correct heading in my .csv files long, lat, Name, Icon.....and use the icon number recommended and nothing.

Bill Clark said...

If you email me your file, I would be happy to look at it.

Harsha said...

Hi Bill,

I have a question & it'll be a great help if you could suggest me with the following.

I have a kml file, created by arcmap 9.3, which iam opening in Google Earth for observations. One of the layers in the arcmap has a "bearing" field, which determines the direction of the arrow icon on the map. The google earth only recognizes "Rotation" tag. As of now, every arrow icon points to "eastward" direction. When converting to kml, could you suggest me anything which can modify the KML in the Arcmap, so that i can insert the tag in the kml generated ?

Bill Clark said...

I am not that familiar with the export functionality of ArcGIS

Unknown said...

Hi Bill,
Thanks for the product. It works great. My question is if I have an altitude with each point is there a way to post it in 3D space?

Thanks again,


Anonymous said...

Do the result from kml file work only on google earth ? coz it's not work in google map , openlayer,... ex: dimension of arrows and arrows color.

Bill Clark said...

Yes, Google Earth only. Google Maps does not support all of the KML features. For example, IconColor and IconHeading are not supported in Maps.

Sarder Printing said...

I just wanted to say thanks for the great resource.

I also need one arrow to another arrow distance with center of the Line.

Please Help me.

Unknown said...

I want to view a spreadsheet on google earth which is made with UTM coordinates. Is it possible? If yes, then how?

Bill Clark said...

The following links are to a sample spreadsheet and the and the resulting map in Google Earth.
1) UtmCoordinates.xlsx
2) UtmCoordinates.kmz

The map was created with the "Excel To Google Earth" utility

Spreadsheet columns
1) Easting - The UTM easting. This example a common case that has easting and northing in separate columns. Note that the Earth Point utilities actually look for the "Position" column (or Latitude and Longitude columns). The Easting and Northing columns are ignored.
2) Northing - UTM Northing.
3) Position - This is the column Earth Point looks for. In this case an Excel formula creates the UTM coordinate using the other data columns.
4) data1 - random data, used to demonstrate the "AppendDataColumnsToDescription" column.
5) test2 - random data
6) field3 - random data
7) Name - The label that appears next to each icon in Google Earth. In this case, an Excel formula uses the spreadsheet row number as the label.
8) Icon - A number that represents an icon from the table at the bottom of the Excel To Google Earth page
9) HideNameUntilMouseOver - reduces map clutter when many icons are located close together.
10) AppendDataColumnsToDescription - an easy way to show the spreadsheet data when each icon is clicked on Google Earth.
11) AppendLatLonToDescription - adds the latitude/longitude conversion to the data in Google Earth.

Other columns that can be added include IconColor and IconScale. These and others are explained on the "Excel To Google Earth" page

Note - if you just need the conversions and not the map, then the same spreadsheet can be run through the "Batch Convert" utility The Batch Convert utility looks for the "Position" column and ignores the others.

Anonymous said...

cómo colocar en el excel para la leyenda.?

Bill Clark said...

The column heading "Name" is used to place a label next to each icon. The column heading "HideNameUntilMouseOver" is a good way to reduce map clutter when several icons are located close together.