quakeforge/include/QF/simd/vec4f.h
2021-03-28 19:49:43 +09:00

350 lines
8.4 KiB
C

/*
QF/simd/vec4f.h
Vector functions for vec4f_t (ie, float precision)
Copyright (C) 2020 Bill Currie <bill@taniwha.org>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
*/
#ifndef __QF_simd_vec4f_h
#define __QF_simd_vec4f_h
#include <immintrin.h>
#include "QF/simd/types.h"
GNU89INLINE inline vec4f_t vabsf (vec4f_t v) __attribute__((const));
GNU89INLINE inline vec4f_t vsqrtf (vec4f_t v) __attribute__((const));
GNU89INLINE inline vec4f_t vceilf (vec4f_t v) __attribute__((const));
GNU89INLINE inline vec4f_t vfloorf (vec4f_t v) __attribute__((const));
GNU89INLINE inline vec4f_t vtruncf (vec4f_t v) __attribute__((const));
/** 3D vector cross product.
*
* The w (4th) component can be any value on input, and is guaranteed to be 0
* in the result. The result is not affected in any way by either vector's w
* componemnt
*/
GNU89INLINE inline vec4f_t crossf (vec4f_t a, vec4f_t b) __attribute__((const));
/** 4D vector dot product.
*
* The w component *IS* significant, but if it is 0 in either vector, then
* the result will be as for a 3D dot product.
*
* Note that the dot product is in all 4 of the return value's elements. This
* helps optimize vector math as the scalar is already pre-spread. If just the
* scalar is required, use result[0].
*/
GNU89INLINE inline vec4f_t dotf (vec4f_t a, vec4f_t b) __attribute__((const));
/** Quaternion product.
*
* The vector is interpreted as a quaternion instead of a regular 4D vector.
* The quaternion may be of any magnitude, so this is more generally useful.
* than if the quaternion was required to be unit length.
*/
GNU89INLINE inline vec4f_t qmulf (vec4f_t a, vec4f_t b) __attribute__((const));
/** Optimized quaterion-vector multiplication for vector rotation.
*
* \note This is the inverse of vqmulf
*
* If the vector's w component is not zero, then the result's w component
* is the cosine of the full rotation angle scaled by the vector's w component.
* The quaternion is assumed to be unit.
*/
GNU89INLINE inline vec4f_t qvmulf (vec4f_t q, vec4f_t v) __attribute__((const));
/** Optimized vector-quaterion multiplication for vector rotation.
*
* \note This is the inverse of qvmulf
*
* If the vector's w component is not zero, then the result's w component
* is the cosine of the full rotation angle scaled by the vector's w component.
* The quaternion is assumed to be unit.
*/
GNU89INLINE inline vec4f_t vqmulf (vec4f_t v, vec4f_t q) __attribute__((const));
/** Create the quaternion representing the shortest rotation from a to b.
*
* Both a and b are assumed to be 3D vectors (w components 0), but a resonable
* (but incorrect) result will still be produced if either a or b is a 4D
* vector. The rotation axis will be the same as if both vectors were 3D, but
* the magnitude of the rotation will be different.
*/
GNU89INLINE inline vec4f_t qrotf (vec4f_t a, vec4f_t b) __attribute__((const));
/** Return the conjugate of the quaternion.
*
* That is, [-x, -y, -z, w].
*/
GNU89INLINE inline vec4f_t qconjf (vec4f_t q) __attribute__((const));
GNU89INLINE inline vec4f_t loadvec3f (const float *v3) __attribute__((pure));
GNU89INLINE inline void storevec3f (float *v3, vec4f_t v4);
GNU89INLINE inline vec4f_t normalf (vec4f_t v) __attribute__((pure));
GNU89INLINE inline vec4f_t magnitudef (vec4f_t v) __attribute__((pure));
GNU89INLINE inline vec4f_t magnitude3f (vec4f_t v) __attribute__((pure));
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
vabsf (vec4f_t v)
{
const uint32_t nan = ~0u >> 1;
const vec4i_t abs = { nan, nan, nan, nan };
return _mm_and_ps (v, (__m128) abs);
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
vsqrtf (vec4f_t v)
{
return _mm_sqrt_ps (v);
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
vceilf (vec4f_t v)
{
return _mm_ceil_ps (v);
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
vfloorf (vec4f_t v)
{
return _mm_floor_ps (v);
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
vtruncf (vec4f_t v)
{
return _mm_round_ps (v, _MM_FROUND_TRUNC);
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
crossf (vec4f_t a, vec4f_t b)
{
static const vec4i_t A = {1, 2, 0, 3};
vec4f_t c = a * __builtin_shuffle (b, A) - __builtin_shuffle (a, A) * b;
return __builtin_shuffle(c, A);
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
dotf (vec4f_t a, vec4f_t b)
{
vec4f_t c = a * b;
c = _mm_hadd_ps (c, c);
c = _mm_hadd_ps (c, c);
return c;
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
qmulf (vec4f_t a, vec4f_t b)
{
// results in [2*as*bs, as*b + bs*a + a x b] ([scalar, vector] notation)
// doesn't seem to adversly affect precision
vec4f_t c = crossf (a, b) + a * b[3] + a[3] * b;
vec4f_t d = dotf (a, b);
// zero out the vector component of dot product so only the scalar remains
d = _mm_insert_ps (d, d, 0xf7);
return c - d;
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
qvmulf (vec4f_t q, vec4f_t v)
{
float s = q[3];
// zero the scalar of the quaternion. Results in an extra operation, but
// avoids adding precision issues.
q = _mm_insert_ps (q, q, 0xf8);
vec4f_t c = crossf (q, v);
vec4f_t qv = dotf (q, v); // q.w is 0 so v.w is irrelevant
vec4f_t qq = dotf (q, q);
return (s * s - qq) * v + 2 * (qv * q + s * c);
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
vqmulf (vec4f_t v, vec4f_t q)
{
float s = q[3];
// zero the scalar of the quaternion. Results in an extra operation, but
// avoids adding precision issues.
q = _mm_insert_ps (q, q, 0xf8);
vec4f_t c = crossf (q, v);
vec4f_t qv = dotf (q, v); // q.w is 0 so v.w is irrelevant
vec4f_t qq = dotf (q, q);
return (s * s - qq) * v + 2 * (qv * q - s * c);
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
qrotf (vec4f_t a, vec4f_t b)
{
vec4f_t ma = vsqrtf (dotf (a, a));
vec4f_t mb = vsqrtf (dotf (b, b));
vec4f_t den = 2 * ma * mb;
vec4f_t t = mb * a + ma * b;
vec4f_t mba_mab = vsqrtf (dotf (t, t));
vec4f_t q = crossf (a, b) / mba_mab;
q[3] = (mba_mab / den)[0];
return q;
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
qconjf (vec4f_t q)
{
const vec4i_t neg = { 1u << 31, 1u << 31, 1u << 31, 0 };
return _mm_xor_ps (q, (__m128) neg);
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
loadvec3f (const float v3[3])
{
vec4f_t v4;
// this had to be in asm otherwise gcc thinks v4 is only partially
// initialized, and gcc 10 does not use the zero flags when generating
// the code, resulting in a memory access to load a 0 into v4[3]
//
// The first instruction zeros v4[3] while loading v4[0]
asm ("\n\
vinsertps $0x08, %1, %0, %0 \n\
vinsertps $0x10, %2, %0, %0 \n\
vinsertps $0x20, %3, %0, %0 \n\
"
: "=v"(v4)
: "m"(v3[0]), "m"(v3[1]), "m"(v3[2]));
return v4;
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
void
storevec3f (float v3[3], vec4f_t v4)
{
v3[0] = v4[0];
v3[1] = v4[1];
v3[2] = v4[2];
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
normalf (vec4f_t v)
{
return v / vsqrtf (dotf (v, v));
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
magnitudef (vec4f_t v)
{
return vsqrtf (dotf (v, v));
}
#ifndef IMPLEMENT_VEC4F_Funcs
GNU89INLINE inline
#else
VISIBLE
#endif
vec4f_t
magnitude3f (vec4f_t v)
{
v[3] = 0;
return vsqrtf (dotf (v, v));
}
vec4f_t __attribute__((pure))
BarycentricCoords_vf (const vec4f_t **points, int num_points, vec4f_t p);
vspheref_t __attribute__((pure))
CircumSphere_vf (const vec4f_t *points, int num_points);
vspheref_t SmallestEnclosingBall_vf (const vec4f_t *points, int num_points);
#endif//__QF_simd_vec4f_h