Introduction The purpose of the exclamation mark (!) in the code from the Point in Polygon Test is to indicate a logical NOT operation. This operation is used to reverse the result of a comparison or a boolean expression. In this particular code, the exclamation mark is used to check if a point is not … Read more
Any non-zero number or non-null pointer is considered to have a logical value of “true”, whereas a number with value 0 or a null pointer is considered to have a logical value of “false”. The ! operator is the logical NOT operator (as opposed to a bit-wise NOT operator). It inverts the logical value of … Read more
Imagine a circle of radius r. It is like a regular polygon with an infinite number of sides. Trigonometry tells us: x = r * cos(a); y = r * sin(a); We know there are 360 degrees or 2pi radians in a circle. So to draw it we would start with angle = 0, calculate … Read more