RTCGETGEOMETRYFIRSTHALFEDGE(3embree3)

✨ rtcGetGeometryFirstHalfEdge ✨</p>

Embree Ray Tracing Kernels 3 — bestie edition 💖

okay so imagine you're deep in your subdivision geometry era and you need to know which half edge kicks off a whole face. that's literally this function. it's giving "first one in the group chat" energy 🎀

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NAME 🌸

rtcGetGeometryFirstHalfEdge — returns the first half edge of a face

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SYNOPSIS 🦋

#include <embree3/rtcore.h>

unsigned int rtcGetGeometryFirstHalfEdge(
  RTCGeometry geometry,
  unsigned int faceID
);

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DESCRIPTION 💅

so the rtcGetGeometryFirstHalfEdge function returns the ID of the first half edge belonging to the face you point at with the faceID argument. no cap.

for instance, in the following example the first half edge of face f1 is e4. slay.

💡 heads up bestie: this function can only be used for subdivision geometries. and since all topologies of a subdivision geometry share the same face buffer, the function does not depend on the topology ID. periodt.

here's the tea 🍓: f0 to f7 are 8 quadrilateral faces with 4 vertices each. the edges e0 to e23 of these faces are shown with their orientation. for each face, the ID of the edges corresponds to the slots the face occupies in the index array of the geometry. like, for example — as the indices of face f1 start at location 4 of the index array, the first edge is edge e4, the next edge e5, etc. it's giving numbered seating chart tbh 🎟️

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EXIT STATUS 😭

on failure an error code is set that can be queried using rtcGetDeviceError. not the vibe, but at least you'll know 💀

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SEE ALSO 🫶</seemint>

• rtcGetGeometryFirstHalfEdge
• rtcGetGeometryFace
• rtcGetGeometryOppositeHalfEdge
• rtcGetGeometryNextHalfEdge
• rtcGetGeometryPreviousHalfEdge

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k that's the whole page bestie, go get those half edges 👑

✿ this has been your girl, signing off — Embree Ray Tracing Kernels 3, rtcGetGeo...stHalfEdge(3) ✿