initial commit, 4.5 stable

thirdparty/embree/kernels/geometry/line_intersector.h

@@ -0,0 +1,145 @@
+// 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<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]); }
+
+        __forceinline Vec2vf<M> uv() const { return Vec2vf<M>(vu,vv); }
+        __forceinline vfloat<M> t () const { return vt; }
+        __forceinline Vec3vf<M> Ng() const { return vNg; }
+        
+      public:
+        vfloat<M> vu;
+        vfloat<M> vv;
+        vfloat<M> vt;
+        Vec3vf<M> vNg;
+      };
+    
+    template<int M>
+      struct FlatLinearCurveIntersector1
+      {
+        typedef CurvePrecalculations1 Precalculations;
+        
+        template<typename Ray, typename Epilog>
+        static __forceinline bool intersect(const vbool<M>& valid_i,
+                                            Ray& ray,
+                                            RayQueryContext* 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<M>(context,geom,ray_org,v0i);
+          const Vec4vf<M> v1 = enlargeRadiusToMinWidth<M>(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,
+                                            RayQueryContext* 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<M>(context,geom,ray_org,v0i);
+          const Vec4vf<M> v1 = enlargeRadiusToMinWidth<M>(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);
+        }
+      };
+  }
+}