rtcSetGeometryBuffer(3)

💖 rtcSetGeometryBuffer — bestie edition 💖

okay so we're deep in the Embree Ray Tracing Kernels 4 era and this page is rtcSetGeometryBuffer(3). it's giving buffer-binding, it's giving geometry glow-up, and yes it's a (3) library call so put your C hat on 🎀

✨ NAME ✨

rtcSetGeometryBuffer — assigns a view of a buffer to the geometry 🫶

✨ SYNOPSIS ✨

#include <embree4/rtcore.h>

void rtcSetGeometryBuffer(
  RTCGeometry geometry,
  enum RTCBufferType type,
  unsigned int slot,
  enum RTCFormat format,
  RTCBuffer buffer,
  size_t byteOffset,
  size_t byteStride,
  size_t itemCount
);

✨ DESCRIPTION ✨

so what this function does, bestie, is it takes a buffer object (that's the buffer argument 🌸) and binds a whole view of it onto a geometry buffer type and slot (the type and slot arguments, respectively) of the geometry you picked (the geometry argument 👑).

and like, you get to be picky about the details, which is the fun part:

• the start of the first buffer element, in bytes — that's the byteOffset argument 📏
• the byte stride between individual buffer elements — that's the byteStride argument
• the format of the buffer elements — that's the format argument ✨
• how many elements you're actually binding — that's the itemCount 💅

⚠️ okay important thing, no cap: the start address (byteOffset argument) and the stride (byteStride argument) must both be aligned to 4 bytes, otherwise rtcSetGeometryBuffer will straight up fail. like, it's not gonna warn you and vibe, it's gonna fail. so align your stuff. periodt 💀

and once this function completes successfully, the geometry will hold a reference to the buffer object 🔥 (yes, a real reference, it's committed, main character energy).

✨ EXIT STATUS ✨

if it fails, an error code gets set that you can go query with rtcGetDeviceError 😭 (go check it, don't just sit there wondering).

✨ SEE ALSO ✨

• rtcSetSharedGeometryBuffer
• rtcSetNewGeometryBuffer

and that's the whole page, bestie 🦋 this was rtcSetGeometryBuffer(3) from the Embree Ray Tracing Kernels 4 era — go bind some buffers, align your bytes, and slay 💅✨