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Merge pull request #14867 from hpvb/optimize-lightbaker-prevent-false-sharing

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Prevent false sharing in lightbaker RNG state
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Rémi Verschelde 2017-12-20 17:36:40 +01:00 committed by GitHub
commit 1040766725
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1 changed files with 7 additions and 2 deletions
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9
scene/3d/voxel_light_baker.cpp
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@ -1711,11 +1711,14 @@ Vector3 VoxelLightBaker::_compute_ray_trace_at_pos(const Vector3 &p_pos, const V
const Light *light = bake_light.ptr();
const Cell *cells = bake_cells.ptr();
// Prevent false sharing when running on OpenMP
uint32_t local_rng_state = *rng_state;
for (int i = 0; i < samples; i++) {
float random_angle1 = (((xorshift32(rng_state) % 65535) / 65535.0) * 2.0 - 1.0) * spread;
float random_angle1 = (((xorshift32(&local_rng_state) % 65535) / 65535.0) * 2.0 - 1.0) * spread;
Vector3 axis(0, sin(random_angle1), cos(random_angle1));
float random_angle2 = ((xorshift32(rng_state) % 65535) / 65535.0) * Math_PI * 2.0;
float random_angle2 = ((xorshift32(&local_rng_state) % 65535) / 65535.0) * Math_PI * 2.0;
Basis rot(Vector3(0, 0, 1), random_angle2);
axis = rot.xform(axis);
@ -1792,6 +1795,8 @@ Vector3 VoxelLightBaker::_compute_ray_trace_at_pos(const Vector3 &p_pos, const V
}
}
// Make sure we don't reset this thread's RNG state
*rng_state = local_rng_state;
return accum / samples;
}