There are several posts on filled polygons that don't show the right colors in GE.

It was discussed that the polygon draw order have to be counter clockwise so the right color will be shown in GE.

I have received few emails asking on how to find out (from the coordinates) if the draw order of a polygon is clockwise or counter clockwise.

Well, it easy. You have to calculate the signed area of the polygon, according to:




If the signed area is negative, the polygon is clockwise. There are other methods.

rs, go on please. Great info.

If you want to correctly show a filled large polygon, not clamped to ground, you can find out the correct altitude to locate your polygon with the following equation:



where Radius is the radius of the earth and length is the maximum length of the polygon (if circle is 2*radius, if square is the side length, for not regular polygon is the maximum axis). Take care with the units for Radius and length.

Add 5-10% to this value to shown a continuous filled color.

(Sorry for the "lenght" in the equation)