65 lines
3.2 KiB
Markdown
65 lines
3.2 KiB
Markdown
|
# Crafter.Math
|
|||
|
|
|
|||
|
|
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, SIMD128 on WebAssembly) and falls back to scalar code elsewhere.
|
|||
|
|
|
|||
|
|
## Modules
|
|||
|
|
|
|||
|
|
`import Crafter.Math;` re-exports the following partitions:
|
|||
|
|
|
|||
|
|
| Partition | Contents |
|
|||
|
|
| --- | --- |
|
|||
|
|
| `:Basic` | `ToRadian`, plus the `VectorF16 → VectorF32` alias on x86_64 without AVX512-FP16. |
|
|||
|
|
| `:Vector` | Generic `Vector<T, Len, Alignment>` with `.x/.y/.z/.w` and `.r/.g/.b/.a` accessors, arithmetic, comparison, and conversion operators. |
|
|||
|
|
| `:MatrixRowMajor` | `MatrixRowMajor<T, ColumnSize, RowSize, Repeats>` — row-major matrices with packed-batch support via `Repeats`. |
|
|||
|
|
| `:VectorF32` | `VectorF32<Len, Packing>` — SIMD-specialized 32-bit float vector with `Load`/`Store`, FMA, `Cross`, `Dot`, `Length`, `Normalize`, `Sin`/`Cos`, `Shuffle`, etc. |
|
|||
|
|
| `:VectorF16` | `VectorF16<Len, Packing>` — same surface as `VectorF32` for `_Float16` when the target supports it. |
|
|||
|
|
| `:Intersection` | `IntersectionTestRayTriangle`, `IntersectionTestRaySphere`, `IntersectionTestRayOrientedBox`. |
|
|||
|
|
| `: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`)
|
|||
|
|
- `Vector-x86-64-v4` — AVX-512 baseline
|
|||
|
|
- `Vector-x86-64-v3` — AVX2 baseline
|
|||
|
|
|
|||
|
|
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.
|
|||
|
|
- **WebAssembly**: `wasm_simd128.h` 128-bit path; SIMD width is capped at 16 bytes.
|
|||
|
|
- **Other targets**: scalar fallback via `std::array<T, N>`.
|
|||
|
|
|
|||
|
|
## License
|
|||
|
|
|
|||
|
|
LGPL-3.0-only. See [LICENSE](LICENSE).
|
|||
|
|
|
|||
|
|
Copyright © 2026 Catcrafts — [catcrafts.net](https://catcrafts.net)
|