godot/thirdparty/embree/kernels/geometry/line_intersector.h
2021-01-14 18:02:07 +01:00

142 lines
6.0 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<int M>
struct LineIntersectorHitM
{
__forceinline LineIntersectorHitM() {}
__forceinline LineIntersectorHitM(const vfloat<M>& u, const vfloat<M>& v, const vfloat<M>& t, const Vec3vf<M>& Ng)
: vu(u), vv(v), vt(t), vNg(Ng) {}
__forceinline void finalize() {}
__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 Vec3fa(vNg.x[i],vNg.y[i],vNg.z[i]); }
public:
vfloat<M> vu;
vfloat<M> vv;
vfloat<M> vt;
Vec3vf<M> vNg;
};
template<int M>
struct FlatLinearCurveIntersector1
{
typedef CurvePrecalculations1 Precalculations;
template<typename Epilog>
static __forceinline bool intersect(const vbool<M>& valid_i,
Ray& ray,
IntersectContext* context,
const LineSegments* geom,
const Precalculations& pre,
const Vec4vf<M>& v0i, const Vec4vf<M>& v1i,
const Epilog& epilog)
{
/* transform end points into ray space */
vbool<M> valid = valid_i;
vfloat<M> depth_scale = pre.depth_scale;
LinearSpace3<Vec3vf<M>> ray_space = pre.ray_space;
const Vec3vf<M> ray_org ((Vec3fa)ray.org);
const Vec4vf<M> v0 = enlargeRadiusToMinWidth(context,geom,ray_org,v0i);
const Vec4vf<M> v1 = enlargeRadiusToMinWidth(context,geom,ray_org,v1i);
Vec4vf<M> p0(xfmVector(ray_space,v0.xyz()-ray_org), v0.w);
Vec4vf<M> p1(xfmVector(ray_space,v1.xyz()-ray_org), v1.w);
/* approximative intersection with cone */
const Vec4vf<M> v = p1-p0;
const Vec4vf<M> w = -p0;
const vfloat<M> d0 = madd(w.x,v.x,w.y*v.y);
const vfloat<M> d1 = madd(v.x,v.x,v.y*v.y);
const vfloat<M> u = clamp(d0*rcp(d1),vfloat<M>(zero),vfloat<M>(one));
const Vec4vf<M> p = madd(u,v,p0);
const vfloat<M> t = p.z;
const vfloat<M> d2 = madd(p.x,p.x,p.y*p.y);
const vfloat<M> r = p.w;
const vfloat<M> r2 = r*r;
valid &= (d2 <= r2) & (vfloat<M>(ray.tnear()) <= t) & (t <= vfloat<M>(ray.tfar));
if (EMBREE_CURVE_SELF_INTERSECTION_AVOIDANCE_FACTOR != 0.0f)
valid &= t > float(EMBREE_CURVE_SELF_INTERSECTION_AVOIDANCE_FACTOR)*r*depth_scale; // ignore self intersections
if (unlikely(none(valid))) return false;
/* ignore denormalized segments */
const Vec3vf<M> T = v1.xyz()-v0.xyz();
valid &= (T.x != vfloat<M>(zero)) | (T.y != vfloat<M>(zero)) | (T.z != vfloat<M>(zero));
if (unlikely(none(valid))) return false;
/* update hit information */
LineIntersectorHitM<M> hit(u,zero,t,T);
return epilog(valid,hit);
}
};
template<int M, int K>
struct FlatLinearCurveIntersectorK
{
typedef CurvePrecalculationsK<K> Precalculations;
template<typename Epilog>
static __forceinline bool intersect(const vbool<M>& valid_i,
RayK<K>& ray, size_t k,
IntersectContext* context,
const LineSegments* geom,
const Precalculations& pre,
const Vec4vf<M>& v0i, const Vec4vf<M>& v1i,
const Epilog& epilog)
{
/* transform end points into ray space */
vbool<M> valid = valid_i;
vfloat<M> depth_scale = pre.depth_scale[k];
LinearSpace3<Vec3vf<M>> ray_space = pre.ray_space[k];
const Vec3vf<M> ray_org(ray.org.x[k],ray.org.y[k],ray.org.z[k]);
const Vec3vf<M> ray_dir(ray.dir.x[k],ray.dir.y[k],ray.dir.z[k]);
const Vec4vf<M> v0 = enlargeRadiusToMinWidth(context,geom,ray_org,v0i);
const Vec4vf<M> v1 = enlargeRadiusToMinWidth(context,geom,ray_org,v1i);
Vec4vf<M> p0(xfmVector(ray_space,v0.xyz()-ray_org), v0.w);
Vec4vf<M> p1(xfmVector(ray_space,v1.xyz()-ray_org), v1.w);
/* approximative intersection with cone */
const Vec4vf<M> v = p1-p0;
const Vec4vf<M> w = -p0;
const vfloat<M> d0 = madd(w.x,v.x,w.y*v.y);
const vfloat<M> d1 = madd(v.x,v.x,v.y*v.y);
const vfloat<M> u = clamp(d0*rcp(d1),vfloat<M>(zero),vfloat<M>(one));
const Vec4vf<M> p = madd(u,v,p0);
const vfloat<M> t = p.z;
const vfloat<M> d2 = madd(p.x,p.x,p.y*p.y);
const vfloat<M> r = p.w;
const vfloat<M> r2 = r*r;
valid &= (d2 <= r2) & (vfloat<M>(ray.tnear()[k]) <= t) & (t <= vfloat<M>(ray.tfar[k]));
if (EMBREE_CURVE_SELF_INTERSECTION_AVOIDANCE_FACTOR != 0.0f)
valid &= t > float(EMBREE_CURVE_SELF_INTERSECTION_AVOIDANCE_FACTOR)*r*depth_scale; // ignore self intersections
if (unlikely(none(valid))) return false;
/* ignore denormalized segments */
const Vec3vf<M> T = v1.xyz()-v0.xyz();
valid &= (T.x != vfloat<M>(zero)) | (T.y != vfloat<M>(zero)) | (T.z != vfloat<M>(zero));
if (unlikely(none(valid))) return false;
/* update hit information */
LineIntersectorHitM<M> hit(u,zero,t,T);
return epilog(valid,hit);
}
};
}
}