A C++23 math library for the Crafter engine, distributed as a set of C++ modules. Provides generic vector and matrix types alongside SIMD-specialized fixed-size vectors for `float` and `_Float16`, plus a small set of ray intersection routines.
The library is hardware-aware: it picks the widest SIMD path the target supports (SSE / AVX / AVX-512 on x86_64, RVV on RISC-V, SIMD128 on WebAssembly) and falls back to scalar code elsewhere.
| `:Common` | Internal SIMD type selection (`__m128/256/512`, `__m128h/256h/512h`, `v128_t`, or scalar array) used by the F16/F32 vectors. |
`Len` is the logical vector width (1–4 for most graphics use) and `Packing` is the number of vectors packed into one SIMD register — e.g. `VectorF32<3, 4>` holds four 3-vectors in a single 512-bit register, which is what the batched `Dot`, `Length`, and `Normalize` overloads operate on.
## Example
```cpp
import Crafter.Math;
using namespace Crafter;
// Generic 3-vector of floats.
Vector<float, 3> a(1.0f, 2.0f, 3.0f);
Vector<float, 3> b(4.0f, 5.0f, 6.0f);
auto c = a + b;
// SIMD-specialized 4-vector with one element of padding.
VectorF32<4, 1> p(1.0f);
VectorF32<4, 1> q(2.0f);
auto r = VectorF32<3, 1>::Cross(p, q);
// Ray vs. triangle.
float t = IntersectionTestRayTriangle<float>(
{0,0,0}, {1,0,0}, {0,1,0},
{0.25f, 0.25f, -1.0f}, {0, 0, 1});
```
## Building
This project uses [Crafter.Build](https://forgejo.catcrafts.net/Catcrafts/Crafter.Build). The build script in [project.cpp](project.cpp) declares the library as a static C++ module library and registers three test executables targeting different ISAs:
-`Vector-sapphirerapids` — AVX-512 with FP16 (`-march=sapphirerapids`)
Build and run tests via your usual Crafter.Build entry point; `build/` and `bin/` are git-ignored.
## Target support
- **x86_64**: SSE / AVX / AVX-512F selected per target; AVX512-FP16 is required for native `VectorF16` (otherwise it aliases `VectorF32`). F16C is used for fp16 ↔ fp32 conversion when available.
- **RISC-V**: RVV 1.0 (the `V` extension, ratified Nov 2021, mandatory in the RVA23 profile). Storage is a 16/32/64-byte GNU vector picked at compile time from the guaranteed VLEN (`__riscv_v_fixed_vlen` from Clang's `-mrvv-vector-bits=`, else `__riscv_v_min_vlen` from the march's `Zvl*` suffix, else the ZVL128B baseline). `VectorF16` aliases `VectorF32` until a `Zvfh` path lands.
