Trigonometric calculation camera Coverage area method

The contents of the previous post record are implemented using algorithms (AS2.0)

function calculates the visible radius (Specify pitch angle: number, specify Tower height: number) {
If (Specify tower height <=0) return 10; The height of the tower in the forest is 0 meters, which is considered to be 10 meters.

Tower height H, earth radius r, place name arc length = square root 2RH
Earth average radius r=6371004; Meters
Visible meter distance =math.sqrt (2*6371004* specified tower height);

Specifies that the gimbal pitch angle be recorded at a Cartesian coordinate system angle. Initialize to positive x axis (i.e. 0 degrees), down to negative angle, tilt upward as positive angle
Specifies the pitch angle%=360; So that its value must be within a circular range
if (Specify Pitch angle >=0| | Specify Pitch angle <=-180)
{
Webcam to day
return visible meter distance;
}
According to the provisions (actual), the pitch angle is generally negative, ZWJ
Trigonometric Functions meters distance =math.tan (math.pi* (90+ specified pitch angle)/180) * Specify tower height;//angle to radians

Returns the smaller
if (Trigonometric meter distance < visible meter distance)
{
return trigonometric meter distance;
}
Else
{
return visible meter distance;
}

}

which uses trigonometric functions to calculate the camera coverage radius r is as follows, h for the camera installation height,