virtualx-engine/thirdparty/embree-aarch64/kernels/geometry/curve_intersector_distance.h
2021-04-23 15:57:28 +02:00

129 lines
4.8 KiB
C++

// Copyright 2009-2020 Intel Corporation
// SPDX-License-Identifier: Apache-2.0
#pragma once
#include "../common/ray.h"
#include "curve_intersector_precalculations.h"
namespace embree
{
namespace isa
{
template<typename NativeCurve3fa, int M>
struct DistanceCurveHit
{
__forceinline DistanceCurveHit() {}
__forceinline DistanceCurveHit(const vbool<M>& valid, const vfloat<M>& U, const vfloat<M>& V, const vfloat<M>& T, const int i, const int N,
const NativeCurve3fa& curve3D)
: U(U), V(V), T(T), i(i), N(N), curve3D(curve3D), valid(valid) {}
__forceinline void finalize()
{
vu = (vfloat<M>(step)+U+vfloat<M>(float(i)))*(1.0f/float(N));
vv = V;
vt = T;
}
__forceinline Vec2f uv (const size_t i) const { return Vec2f(vu[i],vv[i]); }
__forceinline float t (const size_t i) const { return vt[i]; }
__forceinline Vec3fa Ng(const size_t i) const {
return curve3D.eval_du(vu[i]);
}
public:
vfloat<M> U;
vfloat<M> V;
vfloat<M> T;
int i, N;
NativeCurve3fa curve3D;
public:
vbool<M> valid;
vfloat<M> vu;
vfloat<M> vv;
vfloat<M> vt;
};
template<typename NativeCurve3fa>
struct DistanceCurve1Intersector1
{
template<typename Epilog>
__forceinline bool intersect(const CurvePrecalculations1& pre,Ray& ray,
IntersectContext* context,
const CurveGeometry* geom, const unsigned int primID,
const Vec3fa& v0, const Vec3fa& v1, const Vec3fa& v2, const Vec3fa& v3,
const Epilog& epilog)
{
const int N = geom->tessellationRate;
/* transform control points into ray space */
const NativeCurve3fa curve3Di(v0,v1,v2,v3);
const NativeCurve3fa curve3D = enlargeRadiusToMinWidth(context,geom,ray.org,curve3Di);
const NativeCurve3fa curve2D = curve3D.xfm_pr(pre.ray_space,ray.org);
/* evaluate the bezier curve */
vboolx valid = vfloatx(step) < vfloatx(float(N));
const Vec4vfx p0 = curve2D.template eval0<VSIZEX>(0,N);
const Vec4vfx p1 = curve2D.template eval1<VSIZEX>(0,N);
/* approximative intersection with cone */
const Vec4vfx v = p1-p0;
const Vec4vfx w = -p0;
const vfloatx d0 = madd(w.x,v.x,w.y*v.y);
const vfloatx d1 = madd(v.x,v.x,v.y*v.y);
const vfloatx u = clamp(d0*rcp(d1),vfloatx(zero),vfloatx(one));
const Vec4vfx p = madd(u,v,p0);
const vfloatx t = p.z*pre.depth_scale;
const vfloatx d2 = madd(p.x,p.x,p.y*p.y);
const vfloatx r = p.w;
const vfloatx r2 = r*r;
valid &= (d2 <= r2) & (vfloatx(ray.tnear()) <= t) & (t <= vfloatx(ray.tfar));
if (EMBREE_CURVE_SELF_INTERSECTION_AVOIDANCE_FACTOR != 0.0f)
valid &= t > float(EMBREE_CURVE_SELF_INTERSECTION_AVOIDANCE_FACTOR)*r*pre.depth_scale; // ignore self intersections
/* update hit information */
bool ishit = false;
if (unlikely(any(valid))) {
DistanceCurveHit<NativeCurve3fa,VSIZEX> hit(valid,u,0.0f,t,0,N,curve3D);
ishit = ishit | epilog(valid,hit);
}
if (unlikely(VSIZEX < N))
{
/* process SIMD-size many segments per iteration */
for (int i=VSIZEX; i<N; i+=VSIZEX)
{
/* evaluate the bezier curve */
vboolx valid = vintx(i)+vintx(step) < vintx(N);
const Vec4vfx p0 = curve2D.template eval0<VSIZEX>(i,N);
const Vec4vfx p1 = curve2D.template eval1<VSIZEX>(i,N);
/* approximative intersection with cone */
const Vec4vfx v = p1-p0;
const Vec4vfx w = -p0;
const vfloatx d0 = madd(w.x,v.x,w.y*v.y);
const vfloatx d1 = madd(v.x,v.x,v.y*v.y);
const vfloatx u = clamp(d0*rcp(d1),vfloatx(zero),vfloatx(one));
const Vec4vfx p = madd(u,v,p0);
const vfloatx t = p.z*pre.depth_scale;
const vfloatx d2 = madd(p.x,p.x,p.y*p.y);
const vfloatx r = p.w;
const vfloatx r2 = r*r;
valid &= (d2 <= r2) & (vfloatx(ray.tnear()) <= t) & (t <= vfloatx(ray.tfar));
if (EMBREE_CURVE_SELF_INTERSECTION_AVOIDANCE_FACTOR != 0.0f)
valid &= t > float(EMBREE_CURVE_SELF_INTERSECTION_AVOIDANCE_FACTOR)*r*pre.depth_scale; // ignore self intersections
/* update hit information */
if (unlikely(any(valid))) {
DistanceCurveHit<NativeCurve3fa,VSIZEX> hit(valid,u,0.0f,t,i,N,curve3D);
ishit = ishit | epilog(valid,hit);
}
}
}
return ishit;
}
};
}
}