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.rm #[ #] #H #V #F C
.IX Title "trunc Cg"
.TH trunc Cg "" "Cg Toolkit 2.2" "Cg Standard Library"
.UC
.SH "NAME"
\&\fBtrunc\fR \- returns largest integer not greater than a scalar or each
vector component.
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 5
\&  float  trunc(float x);
\&  float1 trunc(float1 x);
\&  float2 trunc(float2 x);
\&  float3 trunc(float3 x);
\&  float4 trunc(float4 x);
.Ve
.Vb 5
\&  half   trunc(half x);
\&  half1  trunc(half1 x);
\&  half2  trunc(half2 x);
\&  half3  trunc(half3 x);
\&  half4  trunc(half4 x);
.Ve
.Vb 5
\&  fixed  trunc(fixed x);
\&  fixed1 trunc(fixed1 x);
\&  fixed2 trunc(fixed2 x);
\&  fixed3 trunc(fixed3 x);
\&  fixed4 trunc(fixed4 x);
.Ve
.SH "PARAMETERS"
.IX Header "PARAMETERS"
.Ip "x" 8
.IX Item "x"
Vector or scalar which to truncate.
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
Returns the integral value nearest to but no larger in magnitude than x.
.SH "REFERENCE IMPLEMENTATION"
.IX Header "REFERENCE IMPLEMENTATION"
\&\fBtrunc\fR for a \fBfloat3\fR vector could be implemented like this.
.PP
.Vb 4
\&  float3 trunc(float3 v)
\&  {
\&    float3 rv;
\&    int i;
.Ve
.Vb 2
\&    for (i=0; i<3; i++) {
\&      float x = v[i];
.Ve
.Vb 4
\&      rv[i] = x < 0 ? -floor(-x) : floor(x);
\&    }
\&    return rv;
\&  }
.Ve
.SH "PROFILE SUPPORT"
.IX Header "PROFILE SUPPORT"
\&\fBtrunc\fR is supported in all profiles except fp20.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
ceil, floor, round
