Manpages - RTCHitN.3embree3

  RTCHitN - hit packet of runtime size

  #include <embree3/rtcore.h>

  struct HitN;

  float& RTCHitN_Ng_x(RTCHitN* hit, unsigned int N, unsigned int i);
  float& RTCHitN_Ng_y(RTCHitN* hit, unsigned int N, unsigned int i);
  float& RTCHitN_Ng_z(RTCHitN* hit, unsigned int N, unsigned int i);

  float& RTCHitN_u(RTCHitN* hit, unsigned int N, unsigned int i);
  float& RTCHitN_v(RTCHitN* hit, unsigned int N, unsigned int i);

  unsigned& RTCHitN_primID(RTCHitN* hit, unsigned int N, unsigned int i);
  unsigned& RTCHitN_geomID(RTCHitN* hit, unsigned int N, unsigned int i);
  unsigned& RTCHitN_instID(RTCHitN* hit, unsigned int N, unsigned int i, unsigned int level);

When the hit packet size is not known at compile time (e.g. when Embree returns a hit packet in the RTCFilterFuncN callback function), Embree uses the RTCHitN type for hit packets. These hit packets can only have sizes of 1, 4, 8, or 16. No other packet size will be used.

You can either implement different special code paths for each of these possible packet sizes and cast the hit to the appropriate hit packet type, or implement one general code path that uses the RTCHitN_XXX helper functions to access hit packet components.

These helper functions get a pointer to the hit packet (hit argument), the packet size (N argument), and returns a reference to a component (e.g. x component of Ng) of the the i-th hit of the packet (i argument).

[RTCRayN]