AngleFromSlope

AngleFromSlope
Header:	Quickdraw.h		Carbon status:	Supported

Converts a slope value to an angle value.

SInt16 AngleFromSlope (
    Fixed slope
);

Parameter descriptions

slope: The slope, defined as Dx/Dy, which is the horizontal change divided by the vertical change between any two points on a line with the slope.

function result: The angle corresponding to the slope specified in the slope parameter treated MOD 180. Angles are defined in clockwise degrees from 12 o’clock. The negative y-axis is defined as being at 12 o’clock, and the positive y-axis at 6 o’clock. The x-axis is defined as usual, with the positive side defined as being at 3 o’clock.

SPECIAL CONSIDERATIONS

The AngleFromSlope function is most useful when you require speed more than accuracy in performing the calculation. The integer result is within 1 degree of the correct answer, but not necessarily within half a degree.

AVAILABILITY

Supported in Carbon. Available in Carbon 1.0.2 and later when running Mac OS 8.1 or later.