The goal is to reduce the affect of the fmod() used in the noise code,
which was initially reported in the comment:
https://projects.blender.org/blender/blender/pulls/119884#issuecomment-1258902
Basic idea is to benefit from SIMD vectorization on CPU.
Tested on Linux i9-11900K and macOS on M2 Ultra, in both cases performance
after this change is very close to what it could be with the fmod() commented
out (the call itself, `p = p + precision_correction`).
On macOS the penalty of fmod() was about 10%, on Linux it was closer to 30%
when built with GCC-13. With Linux builds from the buildbot it is more like 18%.
The optimization is only done for 3d and 4d noise. It might be possible to
gain some performance improvement for 1d and 2d cases, but the approach would
need to be different: we'd need to optimize scalar version fmodf(). Maybe
tricks with integer cast will be faster (since we are a bit optimistic in the
kernel and do not guarantee exact behavior in extreme cases such as NaN inputs).
Pull Request: https://projects.blender.org/blender/blender/pulls/137109
676 lines
16 KiB
C++
676 lines
16 KiB
C++
/* SPDX-FileCopyrightText: 2011-2013 Intel Corporation
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* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
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*
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* SPDX-License-Identifier: Apache-2.0 */
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#pragma once
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#include "util/math_base.h"
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#include "util/math_float4.h"
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#include "util/types_float3.h"
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#include "util/types_float4.h"
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CCL_NAMESPACE_BEGIN
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ccl_device_inline float3 zero_float3()
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{
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#ifdef __KERNEL_SSE__
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return float3(_mm_setzero_ps());
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#else
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return make_float3(0.0f, 0.0f, 0.0f);
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#endif
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}
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ccl_device_inline float3 one_float3()
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{
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return make_float3(1.0f, 1.0f, 1.0f);
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}
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ccl_device_template_spec float3 make_zero()
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{
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return zero_float3();
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}
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ccl_device_inline float3 reciprocal(const float3 a)
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{
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#ifdef __KERNEL_SSE__
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/* Don't use _mm_rcp_ps due to poor precision. */
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return float3(_mm_div_ps(_mm_set_ps1(1.0f), a.m128));
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#else
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return make_float3(1.0f / a.x, 1.0f / a.y, 1.0f / a.z);
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#endif
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}
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#ifndef __KERNEL_METAL__
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ccl_device_inline float3 operator-(const float3 &a)
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{
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# ifdef __KERNEL_SSE__
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return float3(_mm_xor_ps(a.m128, _mm_castsi128_ps(_mm_set1_epi32(0x80000000))));
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# else
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return make_float3(-a.x, -a.y, -a.z);
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# endif
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}
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ccl_device_inline float3 operator*(const float3 a, const float3 b)
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{
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# ifdef __KERNEL_SSE__
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return float3(_mm_mul_ps(a.m128, b.m128));
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# else
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return make_float3(a.x * b.x, a.y * b.y, a.z * b.z);
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# endif
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}
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ccl_device_inline float3 operator*(const float3 a, const float f)
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{
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# ifdef __KERNEL_SSE__
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return float3(_mm_mul_ps(a.m128, _mm_set1_ps(f)));
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# else
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return make_float3(a.x * f, a.y * f, a.z * f);
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# endif
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}
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ccl_device_inline float3 operator*(const float f, const float3 a)
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{
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# if defined(__KERNEL_SSE__)
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return float3(_mm_mul_ps(_mm_set1_ps(f), a.m128));
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# else
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return make_float3(a.x * f, a.y * f, a.z * f);
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# endif
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}
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ccl_device_inline float3 operator/(const float f, const float3 a)
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{
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# if defined(__KERNEL_SSE__)
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return float3(_mm_div_ps(_mm_set1_ps(f), a.m128));
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# else
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return make_float3(f / a.x, f / a.y, f / a.z);
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# endif
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}
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ccl_device_inline float3 operator/(const float3 a, const float f)
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{
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# if defined(__KERNEL_SSE__)
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return float3(_mm_div_ps(a.m128, _mm_set1_ps(f)));
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# else
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float invf = 1.0f / f;
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return make_float3(a.x * invf, a.y * invf, a.z * invf);
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# endif
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}
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ccl_device_inline float3 operator/(const float3 a, const float3 b)
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{
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# if defined(__KERNEL_SSE__)
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return float3(_mm_div_ps(a.m128, b.m128));
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# else
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return make_float3(a.x / b.x, a.y / b.y, a.z / b.z);
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# endif
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}
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ccl_device_inline float3 operator+(const float3 a, const float3 b)
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{
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# ifdef __KERNEL_SSE__
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return float3(_mm_add_ps(a.m128, b.m128));
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# else
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return make_float3(a.x + b.x, a.y + b.y, a.z + b.z);
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# endif
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}
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ccl_device_inline float3 operator+(const float3 a, const float f)
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{
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return a + make_float3(f);
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}
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ccl_device_inline float3 operator-(const float3 a, const float3 b)
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{
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# ifdef __KERNEL_SSE__
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return float3(_mm_sub_ps(a.m128, b.m128));
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# else
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return make_float3(a.x - b.x, a.y - b.y, a.z - b.z);
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# endif
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}
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ccl_device_inline float3 operator-(const float3 a, const float f)
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{
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return a - make_float3(f);
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}
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ccl_device_inline float3 operator+=(float3 &a, const float3 b)
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{
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return a = a + b;
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}
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ccl_device_inline float3 operator-=(float3 &a, const float3 b)
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{
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return a = a - b;
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}
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ccl_device_inline float3 operator*=(float3 &a, const float3 b)
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{
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return a = a * b;
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}
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ccl_device_inline float3 operator*=(float3 &a, const float f)
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{
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return a = a * f;
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}
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ccl_device_inline float3 operator/=(float3 &a, const float3 b)
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{
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return a = a / b;
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}
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ccl_device_inline float3 operator/=(float3 &a, const float f)
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{
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const float invf = 1.0f / f;
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return a = a * invf;
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}
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# if !(defined(__KERNEL_METAL__) || defined(__KERNEL_CUDA__) || defined(__KERNEL_HIP__) || \
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defined(__KERNEL_ONEAPI__))
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ccl_device_inline packed_float3 operator*=(packed_float3 &a, const float3 b)
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{
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a = float3(a) * b;
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return a;
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}
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ccl_device_inline packed_float3 operator*=(packed_float3 &a, const float f)
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{
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a = float3(a) * f;
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return a;
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}
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ccl_device_inline packed_float3 operator/=(packed_float3 &a, const float3 b)
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{
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a = float3(a) / b;
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return a;
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}
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ccl_device_inline packed_float3 operator/=(packed_float3 &a, const float f)
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{
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a = float3(a) / f;
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return a;
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}
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# endif
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ccl_device_inline bool operator==(const float3 a, const float3 b)
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{
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# ifdef __KERNEL_SSE__
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return (_mm_movemask_ps(_mm_cmpeq_ps(a.m128, b.m128)) & 7) == 7;
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# else
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return (a.x == b.x && a.y == b.y && a.z == b.z);
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# endif
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}
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ccl_device_inline bool operator!=(const float3 a, const float3 b)
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{
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return !(a == b);
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}
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ccl_device_inline int3 operator>=(const float3 a, const float3 b)
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{
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# ifdef __KERNEL_SSE__
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return int3(_mm_castps_si128(_mm_cmpge_ps(a.m128, b.m128)));
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# else
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return make_int3(a.x >= b.x, a.y >= b.y, a.z >= b.z);
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# endif
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}
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ccl_device_inline float dot(const float3 a, const float3 b)
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{
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# if defined(__KERNEL_SSE42__) && defined(__KERNEL_SSE__)
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return _mm_cvtss_f32(_mm_dp_ps(a, b, 0x7F));
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# else
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return a.x * b.x + a.y * b.y + a.z * b.z;
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# endif
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}
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#endif
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ccl_device_inline float dot_xy(const float3 a, const float3 b)
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{
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#if defined(__KERNEL_SSE42__) && defined(__KERNEL_SSE__)
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return _mm_cvtss_f32(_mm_hadd_ps(_mm_mul_ps(a, b), b));
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#else
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return a.x * b.x + a.y * b.y;
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#endif
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}
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ccl_device_inline float len(const float3 a)
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{
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#if defined(__KERNEL_SSE42__) && defined(__KERNEL_SSE__)
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return _mm_cvtss_f32(_mm_sqrt_ss(_mm_dp_ps(a.m128, a.m128, 0x7F)));
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#else
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return sqrtf(dot(a, a));
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#endif
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}
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ccl_device_inline float reduce_min(const float3 a)
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{
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return min(min(a.x, a.y), a.z);
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}
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ccl_device_inline float reduce_max(const float3 a)
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{
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return max(max(a.x, a.y), a.z);
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}
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ccl_device_inline float len_squared(const float3 a)
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{
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return dot(a, a);
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}
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#ifndef __KERNEL_METAL__
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ccl_device_inline float distance(const float3 a, const float3 b)
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{
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return len(a - b);
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}
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ccl_device_inline float3 cross(const float3 a, const float3 b)
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{
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# ifdef __KERNEL_SSE__
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const float4 x = float4(a.m128);
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const float4 y = shuffle<1, 2, 0, 3>(float4(b.m128));
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const float4 z = float4(_mm_mul_ps(shuffle<1, 2, 0, 3>(float4(a.m128)), float4(b.m128)));
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return float3(shuffle<1, 2, 0, 3>(msub(x, y, z)).m128);
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# else
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return make_float3(a.y * b.z - a.z * b.y, a.z * b.x - a.x * b.z, a.x * b.y - a.y * b.x);
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# endif
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}
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ccl_device_inline float3 normalize(const float3 a)
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{
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# if defined(__KERNEL_SSE42__) && defined(__KERNEL_SSE__)
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const __m128 norm = _mm_sqrt_ps(_mm_dp_ps(a.m128, a.m128, 0x7F));
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return float3(_mm_div_ps(a.m128, norm));
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# else
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return a / len(a);
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# endif
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}
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ccl_device_inline float3 min(const float3 a, const float3 b)
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{
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# ifdef __KERNEL_SSE__
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return float3(_mm_min_ps(a.m128, b.m128));
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# else
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return make_float3(min(a.x, b.x), min(a.y, b.y), min(a.z, b.z));
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# endif
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}
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ccl_device_inline float3 max(const float3 a, const float3 b)
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{
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# ifdef __KERNEL_SSE__
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return float3(_mm_max_ps(a.m128, b.m128));
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# else
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return make_float3(max(a.x, b.x), max(a.y, b.y), max(a.z, b.z));
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# endif
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}
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ccl_device_inline float3 clamp(const float3 a, const float3 mn, const float3 mx)
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{
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return min(max(a, mn), mx);
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}
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ccl_device_inline float3 fabs(const float3 a)
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{
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# ifdef __KERNEL_SSE__
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# ifdef __KERNEL_NEON__
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return float3(vabsq_f32(a.m128));
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# else
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__m128 mask = _mm_castsi128_ps(_mm_set1_epi32(0x7fffffff));
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return float3(_mm_and_ps(a.m128, mask));
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# endif
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# else
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return make_float3(fabsf(a.x), fabsf(a.y), fabsf(a.z));
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# endif
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}
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/* The floating-point remainder of the division operation a / b calculated by this function is
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* exactly the value a - iquot * b, where iquot is a / b with its fractional part truncated.
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*
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* The returned value has the same sign as a and is less than b in magnitude. */
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ccl_device_inline float3 fmod(const float3 a, const float b)
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{
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# if defined(__KERNEL_NEON__)
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/* Use native Neon instructions.
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* The logic is the same as the SSE code below, but on Apple M2 Ultra this seems to be faster.
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* Possibly due to some runtime checks in _mm_round_ps which do not get properly inlined. */
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const float32x4_t iquot = vrndq_f32(a / b);
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return float3(vsubq_f32(a, vmulq_f32(iquot, vdupq_n_f32(b))));
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# elif defined(__KERNEL_SSE42__) && defined(__KERNEL_SSE__)
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const __m128 iquot = _mm_round_ps(a / b, _MM_FROUND_TRUNC);
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return float3(_mm_sub_ps(a, _mm_mul_ps(iquot, _mm_set1_ps(b))));
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# else
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return make_float3(fmodf(a.x, b), fmodf(a.y, b), fmodf(a.z, b));
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# endif
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}
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ccl_device_inline float3 sqrt(const float3 a)
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{
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# ifdef __KERNEL_SSE__
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return float3(_mm_sqrt_ps(a));
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# else
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return make_float3(sqrtf(a.x), sqrtf(a.y), sqrtf(a.z));
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# endif
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}
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ccl_device_inline float3 floor(const float3 a)
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{
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# ifdef __KERNEL_SSE__
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return float3(_mm_floor_ps(a));
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# else
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return make_float3(floorf(a.x), floorf(a.y), floorf(a.z));
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# endif
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}
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ccl_device_inline float3 ceil(const float3 a)
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{
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# ifdef __KERNEL_SSE__
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return float3(_mm_ceil_ps(a));
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# else
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return make_float3(ceilf(a.x), ceilf(a.y), ceilf(a.z));
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# endif
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}
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ccl_device_inline float3 mix(const float3 a, const float3 b, const float t)
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{
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return a + t * (b - a);
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}
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ccl_device_inline float3 saturate(const float3 a)
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{
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return make_float3(saturatef(a.x), saturatef(a.y), saturatef(a.z));
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}
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ccl_device_inline float3 exp(const float3 v)
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{
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return make_float3(expf(v.x), expf(v.y), expf(v.z));
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}
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ccl_device_inline float3 log(const float3 v)
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{
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return make_float3(logf(v.x), logf(v.y), logf(v.z));
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}
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ccl_device_inline float3 cos(const float3 v)
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{
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return make_float3(cosf(v.x), cosf(v.y), cosf(v.z));
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}
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ccl_device_inline float3 reflect(const float3 incident, const float3 unit_normal)
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{
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return incident - 2.0f * unit_normal * dot(incident, unit_normal);
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}
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ccl_device_inline float3 refract(const float3 incident, const float3 normal, const float eta)
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{
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const float k = 1.0f - eta * eta * (1.0f - dot(normal, incident) * dot(normal, incident));
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if (k < 0.0f) {
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return zero_float3();
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}
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return eta * incident - (eta * dot(normal, incident) + sqrt(k)) * normal;
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}
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ccl_device_inline float3 faceforward(const float3 vector,
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const float3 incident,
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const float3 reference)
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{
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return (dot(reference, incident) < 0.0f) ? vector : -vector;
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}
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#endif
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ccl_device_inline float3 project(const float3 v, const float3 v_proj)
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{
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const float len_squared = dot(v_proj, v_proj);
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return (len_squared != 0.0f) ? (dot(v, v_proj) / len_squared) * v_proj : zero_float3();
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}
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ccl_device_inline float3 normalize_len(const float3 a, ccl_private float *t)
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{
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*t = len(a);
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const float x = 1.0f / *t;
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return a * x;
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}
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ccl_device_inline float3 safe_normalize(const float3 a)
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{
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const float t = len(a);
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return (t != 0.0f) ? a * (1.0f / t) : a;
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}
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ccl_device_inline float3 safe_normalize_fallback(const float3 a, const float3 fallback)
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{
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const float t = len(a);
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return (t != 0.0f) ? a * (1.0f / t) : fallback;
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}
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ccl_device_inline float3 safe_normalize_len(const float3 a, ccl_private float *t)
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{
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*t = len(a);
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return (*t != 0.0f) ? a / (*t) : a;
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}
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ccl_device_inline float3 safe_divide(const float3 a, const float3 b)
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{
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return make_float3((b.x != 0.0f) ? a.x / b.x : 0.0f,
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(b.y != 0.0f) ? a.y / b.y : 0.0f,
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(b.z != 0.0f) ? a.z / b.z : 0.0f);
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}
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ccl_device_inline float3 safe_divide(const float3 a, const float b)
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{
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return (b != 0.0f) ? a / b : zero_float3();
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}
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ccl_device_inline float3 interp(const float3 a, const float3 b, const float t)
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{
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return a + t * (b - a);
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}
|
|
|
|
ccl_device_inline float3 sqr(const float3 a)
|
|
{
|
|
return a * a;
|
|
}
|
|
|
|
ccl_device_inline bool is_zero(const float3 a)
|
|
{
|
|
#ifdef __KERNEL_SSE__
|
|
return a == make_float3(0.0f);
|
|
#else
|
|
return (a.x == 0.0f && a.y == 0.0f && a.z == 0.0f);
|
|
#endif
|
|
}
|
|
|
|
ccl_device_inline float reduce_add(const float3 a)
|
|
{
|
|
#if defined(__KERNEL_SSE__) && defined(__KERNEL_NEON__)
|
|
__m128 t = a.m128;
|
|
t = vsetq_lane_f32(0.0f, t, 3);
|
|
return vaddvq_f32(t);
|
|
#else
|
|
return (a.x + a.y + a.z);
|
|
#endif
|
|
}
|
|
|
|
ccl_device_inline float average(const float3 a)
|
|
{
|
|
return reduce_add(a) * (1.0f / 3.0f);
|
|
}
|
|
|
|
ccl_device_inline bool isequal(const float3 a, const float3 b)
|
|
{
|
|
#if defined(__KERNEL_METAL__)
|
|
return all(a == b);
|
|
#else
|
|
return a == b;
|
|
#endif
|
|
}
|
|
|
|
template<class MaskType>
|
|
ccl_device_inline float3 select(const MaskType mask, const float3 a, const float3 b)
|
|
{
|
|
#if defined(__KERNEL_METAL__)
|
|
return metal::select(b, a, bool3(mask));
|
|
#elif defined(__KERNEL_SSE__)
|
|
# ifdef __KERNEL_SSE42__
|
|
return float3(_mm_blendv_ps(b.m128, a.m128, _mm_castsi128_ps(mask.m128)));
|
|
# else
|
|
return float4(
|
|
_mm_or_ps(_mm_and_ps(_mm_castsi128_ps(mask), a), _mm_andnot_ps(_mm_castsi128_ps(mask), b)));
|
|
# endif
|
|
#else
|
|
return make_float3((mask.x) ? a.x : b.x, (mask.y) ? a.y : b.y, (mask.z) ? a.z : b.z);
|
|
#endif
|
|
}
|
|
|
|
template<class MaskType> ccl_device_inline float3 mask(const MaskType mask, const float3 a)
|
|
{
|
|
/* Replace elements of x with zero where mask isn't set. */
|
|
return select(mask, a, zero_float3());
|
|
}
|
|
|
|
/* Consistent name for this would be pow, but HIP compiler crashes in name mangling. */
|
|
ccl_device_inline float3 power(const float3 v, const float e)
|
|
{
|
|
return make_float3(powf(v.x, e), powf(v.y, e), powf(v.z, e));
|
|
}
|
|
|
|
ccl_device_inline bool isfinite_safe(const float3 v)
|
|
{
|
|
return isfinite_safe(v.x) && isfinite_safe(v.y) && isfinite_safe(v.z);
|
|
}
|
|
|
|
ccl_device_inline float3 ensure_finite(const float3 v)
|
|
{
|
|
float3 r = v;
|
|
if (!isfinite_safe(r.x)) {
|
|
r.x = 0.0f;
|
|
}
|
|
if (!isfinite_safe(r.y)) {
|
|
r.y = 0.0f;
|
|
}
|
|
if (!isfinite_safe(r.z)) {
|
|
r.z = 0.0f;
|
|
}
|
|
return r;
|
|
}
|
|
|
|
/* Triangle */
|
|
|
|
ccl_device_inline float triangle_area(const ccl_private float3 &v1,
|
|
const ccl_private float3 &v2,
|
|
const ccl_private float3 &v3)
|
|
{
|
|
return len(cross(v3 - v2, v1 - v2)) * 0.5f;
|
|
}
|
|
|
|
/* Orthonormal vectors */
|
|
|
|
ccl_device_inline void make_orthonormals(const float3 N,
|
|
ccl_private float3 *a,
|
|
ccl_private float3 *b)
|
|
{
|
|
#if 0
|
|
if (fabsf(N.y) >= 0.999f) {
|
|
*a = make_float3(1, 0, 0);
|
|
*b = make_float3(0, 0, 1);
|
|
return;
|
|
}
|
|
if (fabsf(N.z) >= 0.999f) {
|
|
*a = make_float3(1, 0, 0);
|
|
*b = make_float3(0, 1, 0);
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
if (N.x != N.y || N.x != N.z) {
|
|
*a = make_float3(N.z - N.y, N.x - N.z, N.y - N.x); //(1,1,1)x N
|
|
}
|
|
else {
|
|
*a = make_float3(N.z - N.y, N.x + N.z, -N.y - N.x); //(-1,1,1)x N
|
|
}
|
|
|
|
*a = normalize(*a);
|
|
*b = cross(N, *a);
|
|
}
|
|
|
|
/* Rotation of point around axis and angle */
|
|
|
|
ccl_device_inline float3 rotate_around_axis(const float3 p, const float3 axis, const float angle)
|
|
{
|
|
const float costheta = cosf(angle);
|
|
const float sintheta = sinf(angle);
|
|
float3 r;
|
|
|
|
r.x = ((costheta + (1 - costheta) * axis.x * axis.x) * p.x) +
|
|
(((1 - costheta) * axis.x * axis.y - axis.z * sintheta) * p.y) +
|
|
(((1 - costheta) * axis.x * axis.z + axis.y * sintheta) * p.z);
|
|
|
|
r.y = (((1 - costheta) * axis.x * axis.y + axis.z * sintheta) * p.x) +
|
|
((costheta + (1 - costheta) * axis.y * axis.y) * p.y) +
|
|
(((1 - costheta) * axis.y * axis.z - axis.x * sintheta) * p.z);
|
|
|
|
r.z = (((1 - costheta) * axis.x * axis.z - axis.y * sintheta) * p.x) +
|
|
(((1 - costheta) * axis.y * axis.z + axis.x * sintheta) * p.y) +
|
|
((costheta + (1 - costheta) * axis.z * axis.z) * p.z);
|
|
|
|
return r;
|
|
}
|
|
|
|
/* Calculate the angle between the two vectors a and b.
|
|
* The usual approach `acos(dot(a, b))` has severe precision issues for small angles,
|
|
* which are avoided by this method.
|
|
* Based on "Mangled Angles" from https://people.eecs.berkeley.edu/~wkahan/Mindless.pdf
|
|
*/
|
|
ccl_device_inline float precise_angle(const float3 a, const float3 b)
|
|
{
|
|
return 2.0f * atan2f(len(a - b), len(a + b));
|
|
}
|
|
|
|
/* Tangent of the angle between vectors a and b. */
|
|
ccl_device_inline float tan_angle(const float3 a, const float3 b)
|
|
{
|
|
return len(cross(a, b)) / dot(a, b);
|
|
}
|
|
|
|
/* projections */
|
|
ccl_device_inline float2 map_to_tube(const float3 co)
|
|
{
|
|
float len;
|
|
float u;
|
|
float v;
|
|
len = sqrtf(co.x * co.x + co.y * co.y);
|
|
if (len > 0.0f) {
|
|
u = (1.0f - (atan2f(co.x / len, co.y / len) / M_PI_F)) * 0.5f;
|
|
v = (co.z + 1.0f) * 0.5f;
|
|
}
|
|
else {
|
|
u = v = 0.0f;
|
|
}
|
|
return make_float2(u, v);
|
|
}
|
|
|
|
ccl_device_inline float2 map_to_sphere(const float3 co)
|
|
{
|
|
const float l = dot(co, co);
|
|
float u;
|
|
float v;
|
|
if (l > 0.0f) {
|
|
if (UNLIKELY(co.x == 0.0f && co.y == 0.0f)) {
|
|
u = 0.0f; /* Otherwise domain error. */
|
|
}
|
|
else {
|
|
u = (0.5f - atan2f(co.x, co.y) * M_1_2PI_F);
|
|
}
|
|
v = 1.0f - safe_acosf(co.z / sqrtf(l)) * M_1_PI_F;
|
|
}
|
|
else {
|
|
u = v = 0.0f;
|
|
}
|
|
return make_float2(u, v);
|
|
}
|
|
|
|
CCL_NAMESPACE_END
|