multithreaded simd Raytracer for Voxel Engines
C99 sse4 + pthreads CPU grid-aligned voxel raytracer created for internal needs of Lum engine
#define every RAVE_* define you need before any of raytracer.* files included
- Include raytracer.h wherever you need
- Compile raytracer.c (if using any defines, make sure they are defined)
- Link with compiled object file
You may also just compile one of your objects files with raytracer.c included, just make sure that you link with only one implementation
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to use custom voxel type instead of uint8_t use
#define RAVE_CUSTOM_VOXEL_TYPE custom_voxel_type //uint8_t is defualt #include "raytracer.h"
to disable SIMD use
#define RAVE_NO_SIMD #include "raytracer.h"
you need to implement all of the following functions in your code to make RaVE be able to interact with your voxel engine:
rave_voxel rave_get_voxel(int x, int y, int z);
rave_vec3 rave_get_ray_pos(int local_x, int local_y, int local_z);
rave_vec3 rave_get_ray_dir(int local_x, int local_y, int local_z);
void rave_store_light(int local_x, int local_y, int local_z, rave_vec3 light);
Material rave_get_material(rave_voxel voxel);Also, create and set following variables
uint32_t max_steps; //steps taken before no-hit return
uint32_t max_reflections; //typically 7 is enough
rave_voxel rave_empty_voxel; //typically you would want it to be 0rave_get_voxel(x,y,z) should return voxel in (x,y,z) position in voxel world space.
rave_get_material(voxel) should return voxel's material
Material represents simple reflectance distribution function, with 3-float color, float emmitance and float roughness parameters
use rave_dispatch(int count_x, int count_y, int count_z) to do calculations. This will trace count_x * count_y * count_z rays. Every ray will get its origin via rave_get_ray_pos(x,y,z), direction via rave_get_ray_dir(x,y,z) and will store raytraced light via rave_store_light(x,y,z)
typically you will only need one or two dimensions for dispatch, but third one can be used for multisampling
see tests/test.c (Cornell box) and tests/fractal.c (weirdly-colored voxelized Julia set) You can build them with Make (make test / make fractal)
MIT