clockwise angle between two line
I want to calculate a clockwise angle between two line segment A and B. So the resulting angle must be between 0 to 360-1 degrees. I've seen all other answers in SO but they gave me negative angle开发者_运维知识库s. Thanks.
For turning any angle into a 0-359 range in C#, you can use the following "algorithm":
public int Normalise (int degrees) {
int retval = degrees % 360;
if (retval < 0)
retval += 360;
return retval;
}
C# follows the same rules as C and C++ and i % 360
will give you a value between -359
and 359
for any integer, then the second line is to ensure it's in the range 0 through 359 inclusive.
A sneaky version on one line:
degrees = ((degrees % 360) + 360) % 360;
which would normalise it under all conditions. I'm not sure I'd worry too much about using the inline one-liner unless performance was critical, but I will explain it.
From degrees % 360
, you will get a number between -359
and 359
. Adding 360
will modify the range to between 1
and 729
. Then the final % 360
will bring it back to the range 0
through 359
.
I would try :
if degrees is between [-360, 360]
degrees = (degrees + 360) % 360;
else degrees = (degrees % 360) + 360) % 360;
Surely you could adapt any solution with negative angles to always be 0-360 by adjusting:
float positive = (angle < 0) ? (360 + angle) : angle
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