Rechercher une page de manuel

log.3Cg

Langue: en

Version: 354388 (ubuntu - 24/10/10)

Section: 3 (Bibliothèques de fonctions)

log - returns the natural logarithm of scalars and vectors

   float  log(float a);
   float1 log(float1 a);
   float2 log(float2 a);
   float3 log(float3 a);
   float4 log(float4 a);

   half   log(half a);
   half1  log(half1 a);
   half2  log(half2 a);
   half3  log(half3 a);
   half4  log(half4 a);

   fixed  log(fixed a);
   fixed1 log(fixed1 a);
   fixed2 log(fixed2 a);
   fixed3 log(fixed3 a);
   fixed4 log(fixed4 a);

Returns the natural logarithm a.

For vectors, the returned vector contains the natural logarithm of each element of the input vector.

   float3 log(float3 a)
   {
     float3 rv;
     int i;

     for (i=0; i<3; i++) {
       rv[i] = log(a[i]);  // this is the ANSI C standard library log()
     }
     return rv;
   }

log is typically implemented with a native base-2 logarithm instruction.

log is fully supported in all profiles unless otherwise specified.

Support in the fp20 is limited to constant compile-time evaluation.