Revision control
++ // Copyright 2009-2021 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;
++ }
++ };
++ }
++ }