RTCFeatureFlags(3)

✨ NAME ✨

RTCFeatureFlags — it's the enum that says which ray-tracing features you're enabling, bestie 💅

This one lives in the Embree Ray Tracing Kernels 4 manual, section 3, and it's giving "pick your features, queen" energy 👑

🎀 SYNOPSIS 🎀

#include <embree4/rtcore_ray.h>

enum RTCFeatureFlags
{
  RTC_FEATURE_FLAG_NONE = 0,

  RTC_FEATURE_FLAG_MOTION_BLUR = 1 << 0,

  RTC_FEATURE_FLAG_TRIANGLE = 1 << 1,
  RTC_FEATURE_FLAG_QUAD = 1 << 2,
  RTC_FEATURE_FLAG_GRID = 1 << 3,
  RTC_FEATURE_FLAG_SUBDIVISION = 1 << 4,
  RTC_FEATURE_FLAG_POINT = ... ,
  RTC_FEATURE_FLAG_CURVES = ... ,

  RTC_FEATURE_FLAG_CONE_LINEAR_CURVE = 1 << 5,
  RTC_FEATURE_FLAG_ROUND_LINEAR_CURVE  = 1 << 6,
  RTC_FEATURE_FLAG_FLAT_LINEAR_CURVE = 1 << 7,

  RTC_FEATURE_FLAG_ROUND_BEZIER_CURVE = 1 << 8,
  RTC_FEATURE_FLAG_FLAT_BEZIER_CURVE = 1 << 9,
  RTC_FEATURE_FLAG_NORMAL_ORIENTED_BEZIER_CURVE = 1 << 10,

  RTC_FEATURE_FLAG_ROUND_BSPLINE_CURVE = 1 << 11,
  RTC_FEATURE_FLAG_FLAT_BSPLINE_CURVE = 1 << 12,
  RTC_FEATURE_FLAG_NORMAL_ORIENTED_BSPLINE_CURVE = 1 << 13,

  RTC_FEATURE_FLAG_ROUND_HERMITE_CURVE = 1 << 14,
  RTC_FEATURE_FLAG_FLAT_HERMITE_CURVE = 1 << 15,
  RTC_FEATURE_FLAG_NORMAL_ORIENTED_HERMITE_CURVE = 1 << 16,

  RTC_FEATURE_FLAG_ROUND_CATMULL_ROM_CURVE = 1 << 17,
  RTC_FEATURE_FLAG_FLAT_CATMULL_ROM_CURVE = 1 << 18,
  RTC_FEATURE_FLAG_NORMAL_ORIENTED_CATMULL_ROM_CURVE = 1 << 19,

  RTC_FEATURE_FLAG_SPHERE_POINT = 1 << 20,
  RTC_FEATURE_FLAG_DISC_POINT = 1 << 21,
  RTC_FEATURE_FLAG_ORIENTED_DISC_POINT = 1 << 22,

  RTC_FEATURE_FLAG_ROUND_CURVES = ... ,
  RTC_FEATURE_FLAG_FLAT_CURVES = ... ,
  RTC_FEATURE_FLAG_NORMAL_ORIENTED_CURVES = ... ,

  RTC_FEATURE_FLAG_LINEAR_CURVES = ... ,
  RTC_FEATURE_FLAG_BEZIER_CURVES = ... ,
  RTC_FEATURE_FLAG_BSPLINE_CURVES = ... ,
  RTC_FEATURE_FLAG_HERMITE_CURVES = ... ,

  RTC_FEATURE_FLAG_INSTANCE = 1 << 23,

  RTC_FEATURE_FLAG_FILTER_FUNCTION_IN_ARGUMENTS = 1 << 24,
  RTC_FEATURE_FLAG_FILTER_FUNCTION_IN_GEOMETRY = 1 << 25,
  RTC_FEATURE_FLAG_FILTER_FUNCTION = ... ,

  RTC_FEATURE_FLAG_USER_GEOMETRY_CALLBACK_IN_ARGUMENTS = 1 << 26,
  RTC_FEATURE_FLAG_USER_GEOMETRY_CALLBACK_IN_GEOMETRY = 1 << 27,
  RTC_FEATURE_FLAG_USER_GEOMETRY = ... ,

  RTC_FEATURE_FLAG_32_BIT_RAY_MASK = 1 << 28,

  RTC_FEATURE_FLAG_ALL = 0xffffffff
};

🌸 DESCRIPTION 🌸

okay so. RTCFeatureFlags is an enum that's literally just a bit mask, and its whole job is to turn specific ray tracing features on for ray query operations ✨ You hand these feature flags over to the rtcIntersect1/4/8/16 and rtcOccluded1/4/8/16 functions, passing them through the RTCIntersectArguments and RTCOccludedArguments structures 🫶

The rule is simple, bestie: only a ray tracing feature whose bit is enabled in the feature mask can get used 💅

And if a feature bit is NOT set? The behaviour is undefined. Not "it fails politely," not "it errors out" — undefined. So the feature may work or it may not. It's giving chaos 🙈

If you want multiple features, you combine them with a bitwise OR operation. That's it, that's the whole trick 🔥

Why does this exist, though? The purpose of feature flags is to reduce code size on the GPU by enabling just the features you actually need to render your scene 🎀 On the CPU there's genuinely no need to use feature flags at all, and you can just keep the default of all features enabled (RTC_FEATURE_FLAG_ALL). Slay, no notes 💖

Here's every feature you can switch on, one by one 👇

• RTC_FEATURE_FLAG_MOTION_BLUR — turns on motion blur for all geometry types 💫
• RTC_FEATURE_FLAG_TRIANGLE — turns on triangle geometries (RTC_GEOMETRY_TYPE_TRIANGLE) 🔺
• RTC_FEATURE_FLAG_QUAD — turns on quad geometries (RTC_GEOMETRY_TYPE_QUAD) 🔷
• RTC_FEATURE_FLAG_GRID — turns on grid geometries (RTC_GEOMETRY_TYPE_GRID) 🕸️
• RTC_FEATURE_FLAG_SUBDIVISION — turns on subdivision geometries (RTC_GEOMETRY_TYPE_SUBDIVISION) 🧊
• RTC_FEATURE_FLAG_POINT — turns on all point geometry types (RTC_GEOMETRY_TYPE_XXX_POINT) 🍓
• RTC_FEATURE_FLAG_CURVES — turns on all curve geometry types (RTC_GEOMETRY_TYPE_XXX_YYY_CURVE) 🦋
• RTC_FEATURE_FLAG_ROUND_CURVES — turns on all round curves (RTC_GEOMETRY_TYPE_ROUND_XXX_CURVE) 🌸
• RTC_FEATURE_FLAG_FLAT_CURVES — turns on all flat curves (RTC_GEOMETRY_TYPE_FLAT_XXX_CURVE) 🎀
• RTC_FEATURE_FLAG_NORMAL_ORIENTED_CURVES — turns on all normal oriented curves (RTC_GEOMETRY_TYPE_NORMAL_ORIENTED_XXX_CURVE) 🧭
• RTC_FEATURE_FLAG_LINEAR_CURVES — turns on all linear curves (RTC_GEOMETRY_TYPE_XXX_LINEAR_CURVE) 📏
• RTC_FEATURE_FLAG_BEZIER_CURVES — turns on all Bézier curves (RTC_GEOMETRY_TYPE_XXX_BEZIER_CURVE) ✨
• RTC_FEATURE_FLAG_BSPLINE_CURVES — turns on all B-spline curves (RTC_GEOMETRY_TYPE_XXX_BSPLINE_CURVE) 🌀
• RTC_FEATURE_FLAG_HERMITE_CURVES — turns on all Hermite curves (RTC_GEOMETRY_TYPE_XXX_HERMITE_CURVE) 🌿
• RTC_FEATURE_FLAG_CONE_LINEAR_CURVE — turns on the cone geometry type (RTC_GEOMETRY_TYPE_CONE_LINEAR_CURVE) 🍦
• RTC_FEATURE_FLAG_ROUND_LINEAR_CURVE — turns on round linear curves (RTC_GEOMETRY_TYPE_ROUND_LINEAR_CURVE) 💜
• RTC_FEATURE_FLAG_FLAT_LINEAR_CURVE — turns on flat linear curves (RTC_GEOMETRY_TYPE_FLAT_LINEAR_CURVE) 📐
• RTC_FEATURE_FLAG_ROUND_BEZIER_CURVE — turns on round Bézier curves (RTC_GEOMETRY_TYPE_ROUND_BEZIER_CURVE) 🎈
• RTC_FEATURE_FLAG_FLAT_BEZIER_CURVE — turns on flat Bézier curves (RTC_GEOMETRY_TYPE_FLAT_BEZIER_CURVE) 🎨
• RTC_FEATURE_FLAG_NORMAL_ORIENTED_BEZIER_CURVE — turns on normal oriented Bézier curves (RTC_GEOMETRY_TYPE_NORMAL_ORIENTED_BEZIER_CURVE) 🧭
• RTC_FEATURE_FLAG_ROUND_BSPLINE_CURVE — turns on round B-spline curves (RTC_GEOMETRY_TYPE_ROUND_BSPLINE_CURVE) 🌈
• RTC_FEATURE_FLAG_FLAT_BSPLINE_CURVE — turns on flat B-spline curves (RTC_GEOMETRY_TYPE_FLAT_BSPLINE_CURVE) 🌊
• RTC_FEATURE_FLAG_NORMAL_ORIENTED_BSPLINE_CURVE — turns on normal oriented B-spline curves (RTC_GEOMETRY_TYPE_NORMAL_ORIENTED_BSPLINE_CURVE) 🧭
• RTC_FEATURE_FLAG_ROUND_HERMITE_CURVE — turns on round Hermite curves (RTC_GEOMETRY_TYPE_ROUND_HERMITE_CURVE) 💫
• RTC_FEATURE_FLAG_FLAT_HERMITE_CURVE — turns on flat Hermite curves (RTC_GEOMETRY_TYPE_FLAT_HERMITE_CURVE) 🍃
• RTC_FEATURE_FLAG_NORMAL_ORIENTED_HERMITE_CURVE — turns on normal oriented Hermite curves (RTC_GEOMETRY_TYPE_NORMAL_ORIENTED_HERMITE_CURVE) 🧭
• RTC_FEATURE_FLAG_ROUND_CATMULL_ROM_CURVE — turns on round Catmull Rom curves (RTC_GEOMETRY_TYPE_ROUND_CATMULL_ROM_CURVE) 🌀
• RTC_FEATURE_FLAG_FLAT_CATMULL_ROM_CURVE — turns on flat Catmull Rom curves (RTC_GEOMETRY_TYPE_FLAT_CATMULL_ROM_CURVE) 🧵
• RTC_FEATURE_FLAG_NORMAL_ORIENTED_CATMULL_ROM_CURVE — turns on normal oriented Catmull Rom curves (RTC_GEOMETRY_TYPE_NORMAL_ORIENTED_CATMULL_ROM_CURVE) 🧭
• RTC_FEATURE_FLAG_SPHERE_POINT — turns on the sphere geometry type (RTC_GEOMETRY_TYPE_SPHERE_POINT) 🔮
• RTC_FEATURE_FLAG_DISC_POINT — turns on the disc geometry type (RTC_GEOMETRY_TYPE_DISC_POINT) 💿
• RTC_FEATURE_FLAG_ORIENTED_DISC_POINT — turns on oriented disc geometry types (RTC_GEOMETRY_TYPE_ORIENTED_DISC_POINT) 🪩
• RTC_FEATURE_FLAG_INSTANCE — turns on instance geometries (RTC_GEOMETRY_TYPE_INSTANCE) 🪆
• RTC_FEATURE_FLAG_FILTER_FUNCTION_IN_ARGUMENTS — turns on filter functions passed through intersect arguments 🫧
• RTC_FEATURE_FLAG_FILTER_FUNCTION_IN_GEOMETRY — turns on filter functions passed through geometry 🫧
• RTC_FEATURE_FLAG_FILTER_FUNCTION — turns on filter functions (both the argument version and the geometry version) 🫧
• RTC_FEATURE_FLAG_USER_GEOMETRY_CALLBACK_IN_ARGUMENTS — turns on RTC_GEOMETRY_TYPE_USER with the function pointer passed through intersect arguments 🧚
• RTC_FEATURE_FLAG_USER_GEOMETRY_CALLBACK_IN_GEOMETRY — turns on RTC_GEOMETRY_TYPE_USER with the function pointer passed through the geometry object 🧚
• RTC_FEATURE_FLAG_USER_GEOMETRY — turns on RTC_GEOMETRY_TYPE_USER geometries (both the argument callback version and the geometry callback version) 🧚
• RTC_FEATURE_FLAG_32_BIT_RAY_MASK — turns on full 32 bit ray masks. If you don't use this one, only the lower 7 bits in the ray mask are handled correctly ⚠️
• RTC_FEATURE_FLAG_ALL — turns on all the features (this is the default) 👑

💀 EXIT STATUS 💀

crickets. Bestie there is literally nothing in this section. Not a single exit status. It's giving empty group chat at 3am 😭 Moving on 💅

🫶 SEE ALSO 🫶

• rtcIntersect1
• rtcIntersect4/8/16
• rtcOccluded1
• rtcOccluded4/8/16

and that's the whole page, babe 💖 It came from the Embree Ray Tracing Kernels 4 docs and it's filed under RTCFeatureFlags(3) — go enable exactly the features you need, keep RTC_FEATURE_FLAG_ALL on the CPU, and remember: unset bits are undefined behaviour, so don't play with that. periodt 🎀✨