NAME
atan - returns arctangent of scalars and vectors.
SYNOPSIS
float atan(float a); float1 atan(float1 a); float2 atan(float2 a); float3 atan(float3 a); float4 atan(float4 a); half atan(half a); half1 atan(half1 a); half2 atan(half2 a); half3 atan(half3 a); half4 atan(half4 a); fixed atan(fixed a); fixed1 atan(fixed1 a); fixed2 atan(fixed2 a); fixed3 atan(fixed3 a); fixed4 atan(fixed4 a);PARAMETERS
- a
Vector or scalar of which to determine the arctangent.
DESCRIPTION
Returns the arctangent of x in the range of -pi/2 to pi/2 radians.
For vectors, the returned vector contains the arctangent of each element of the input vector.
REFERENCE IMPLEMENTATION
atan for a float scalar could be implemented like this.
float atan(float x) { return atan2(x, float(1)); }atan2 is typically implemented as an approximation.
PROFILE SUPPORT
atan is supported in all profiles but fp20.
SEE ALSO