NAME
atan - returns arctangent of scalars and vectors.
SYNOPSIS
float atan( float a ); float1 atan( float2 a ); float2 atan( float2 a ); float3 atan( float3 a ); float4 atan( float4 a ); half atan( half a ); half1 atan( half2 a ); half2 atan( half2 a ); half3 atan( half3 a ); half4 atan( half4 a ); fixed atan( fixed a ); fixed1 atan( fixed2 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 except fp20.
SEE ALSO