Noise

RtInt RxNoise(int inDimension, float *in,
              int outDimension, float *out);
RtInt RxPNoise(int inDimension, float *in, float *period,
               int outDimension, float *out);
RtInt RxCellNoise(int inDimension, float *in,
                  int outDimension, float *out);

Texture Lookup

RtInt RxEnvironment(RtString filename, RtInt firstchannel,
                    RtInt nchannels, RtPoint dir0, RtPoint dir1, RtPoint dir2, RtPoint dir3,
                    RtFloat *result, …);
RtInt RxShadow(RtString filename, RtInt firstchannel,
               RtPoint P0, RtPoint P1, RtPoint P2, RtPoint P3, RtFloat *result, …);
RtInt RxTexture(RtString filename, RtInt firstchannel, RtInt nchannels,
                RtFloat s0, RtFloat t0, RtFloat s1, RtFloat t1, RtFloat s2, RtFloat t2,
                RtFloat s3, RtFloat t3, RtFloat *result, …);

3D Texture Write and Lookup

RtInt RxBake3d(RtString filename, RtPoint point, RtNormal normal, RtFloat radius, …);
RtInt RxTexture3d(RtString filename, RtPoint point, RtNormal normal, RtFloat filterradius, …);

Attribute and Option State

RtInt RxAttribute (const char *name, void *result, 
                   int resultlen, RxInfoType_t *resulttype, int *resultcount);
RtInt RxOption (const char *name, void *result, int resultlen,
                RxInfoType_t *resulttype, int *resultcount);

Renderer Information

RtInt RxRendererInfo (const char *name, void *result, int resultlen, 
                      RxInfoType_t *resulttype, int *resultcount);