godot/thirdparty/embree/common/math/lbbox.h
2021-01-14 18:02:07 +01:00

290 lines
10 KiB
C++

// Copyright 2009-2020 Intel Corporation
// SPDX-License-Identifier: Apache-2.0
#pragma once
#include "bbox.h"
#include "range.h"
namespace embree
{
template<typename T>
__forceinline std::pair<T,T> globalLinear(const std::pair<T,T>& v, const BBox1f& dt)
{
const float rcp_dt_size = float(1.0f)/dt.size();
const T g0 = lerp(v.first,v.second,-dt.lower*rcp_dt_size);
const T g1 = lerp(v.first,v.second,(1.0f-dt.lower)*rcp_dt_size);
return std::make_pair(g0,g1);
}
template<typename T>
struct LBBox
{
public:
__forceinline LBBox () {}
template<typename T1>
__forceinline LBBox ( const LBBox<T1>& other )
: bounds0(other.bounds0), bounds1(other.bounds1) {}
__forceinline LBBox& operator= ( const LBBox& other ) {
bounds0 = other.bounds0; bounds1 = other.bounds1; return *this;
}
__forceinline LBBox (EmptyTy)
: bounds0(EmptyTy()), bounds1(EmptyTy()) {}
__forceinline explicit LBBox ( const BBox<T>& bounds)
: bounds0(bounds), bounds1(bounds) { }
__forceinline LBBox ( const BBox<T>& bounds0, const BBox<T>& bounds1)
: bounds0(bounds0), bounds1(bounds1) { }
LBBox ( const avector<BBox<T>>& bounds )
{
assert(bounds.size());
BBox<T> b0 = bounds.front();
BBox<T> b1 = bounds.back();
for (size_t i=1; i<bounds.size()-1; i++) {
const float f = float(i)/float(bounds.size()-1);
const BBox<T> bt = lerp(b0,b1,f);
const T dlower = min(bounds[i].lower-bt.lower,T(zero));
const T dupper = max(bounds[i].upper-bt.upper,T(zero));
b0.lower += dlower; b1.lower += dlower;
b0.upper += dupper; b1.upper += dupper;
}
bounds0 = b0;
bounds1 = b1;
}
/*! calculates the linear bounds of a primitive for the specified time range */
template<typename BoundsFunc>
__forceinline LBBox(const BoundsFunc& bounds, const BBox1f& time_range, float numTimeSegments)
{
const float lower = time_range.lower*numTimeSegments;
const float upper = time_range.upper*numTimeSegments;
const float ilowerf = floor(lower);
const float iupperf = ceil(upper);
const int ilower = (int)ilowerf;
const int iupper = (int)iupperf;
const BBox<T> blower0 = bounds(ilower);
const BBox<T> bupper1 = bounds(iupper);
if (iupper-ilower == 1) {
bounds0 = lerp(blower0, bupper1, lower-ilowerf);
bounds1 = lerp(bupper1, blower0, iupperf-upper);
return;
}
const BBox<T> blower1 = bounds(ilower+1);
const BBox<T> bupper0 = bounds(iupper-1);
BBox<T> b0 = lerp(blower0, blower1, lower-ilowerf);
BBox<T> b1 = lerp(bupper1, bupper0, iupperf-upper);
for (int i = ilower+1; i < iupper; i++)
{
const float f = (float(i)/numTimeSegments - time_range.lower) / time_range.size();
const BBox<T> bt = lerp(b0, b1, f);
const BBox<T> bi = bounds(i);
const T dlower = min(bi.lower-bt.lower, T(zero));
const T dupper = max(bi.upper-bt.upper, T(zero));
b0.lower += dlower; b1.lower += dlower;
b0.upper += dupper; b1.upper += dupper;
}
bounds0 = b0;
bounds1 = b1;
}
/*! calculates the linear bounds of a primitive for the specified time range */
template<typename BoundsFunc>
__forceinline LBBox(const BoundsFunc& bounds, const BBox1f& time_range_in, const BBox1f& geom_time_range, float geom_time_segments)
{
/* normalize global time_range_in to local geom_time_range */
const BBox1f time_range((time_range_in.lower-geom_time_range.lower)/geom_time_range.size(),
(time_range_in.upper-geom_time_range.lower)/geom_time_range.size());
const float lower = time_range.lower*geom_time_segments;
const float upper = time_range.upper*geom_time_segments;
const float ilowerf = floor(lower);
const float iupperf = ceil(upper);
const float ilowerfc = max(0.0f,ilowerf);
const float iupperfc = min(iupperf,geom_time_segments);
const int ilowerc = (int)ilowerfc;
const int iupperc = (int)iupperfc;
assert(iupperc-ilowerc > 0);
/* this larger iteration range guarantees that we process borders of geom_time_range is (partially) inside time_range_in */
const int ilower_iter = max(-1,(int)ilowerf);
const int iupper_iter = min((int)iupperf,(int)geom_time_segments+1);
const BBox<T> blower0 = bounds(ilowerc);
const BBox<T> bupper1 = bounds(iupperc);
if (iupper_iter-ilower_iter == 1) {
bounds0 = lerp(blower0, bupper1, max(0.0f,lower-ilowerfc));
bounds1 = lerp(bupper1, blower0, max(0.0f,iupperfc-upper));
return;
}
const BBox<T> blower1 = bounds(ilowerc+1);
const BBox<T> bupper0 = bounds(iupperc-1);
BBox<T> b0 = lerp(blower0, blower1, max(0.0f,lower-ilowerfc));
BBox<T> b1 = lerp(bupper1, bupper0, max(0.0f,iupperfc-upper));
for (int i = ilower_iter+1; i < iupper_iter; i++)
{
const float f = (float(i)/geom_time_segments - time_range.lower) / time_range.size();
const BBox<T> bt = lerp(b0, b1, f);
const BBox<T> bi = bounds(i);
const T dlower = min(bi.lower-bt.lower, T(zero));
const T dupper = max(bi.upper-bt.upper, T(zero));
b0.lower += dlower; b1.lower += dlower;
b0.upper += dupper; b1.upper += dupper;
}
bounds0 = b0;
bounds1 = b1;
}
/*! calculates the linear bounds of a primitive for the specified time range */
template<typename BoundsFunc>
__forceinline LBBox(const BoundsFunc& bounds, const range<int>& time_range, int numTimeSegments)
{
const int ilower = time_range.begin();
const int iupper = time_range.end();
BBox<T> b0 = bounds(ilower);
BBox<T> b1 = bounds(iupper);
if (iupper-ilower == 1)
{
bounds0 = b0;
bounds1 = b1;
return;
}
for (int i = ilower+1; i<iupper; i++)
{
const float f = float(i - time_range.begin()) / float(time_range.size());
const BBox<T> bt = lerp(b0, b1, f);
const BBox<T> bi = bounds(i);
const T dlower = min(bi.lower-bt.lower, T(zero));
const T dupper = max(bi.upper-bt.upper, T(zero));
b0.lower += dlower; b1.lower += dlower;
b0.upper += dupper; b1.upper += dupper;
}
bounds0 = b0;
bounds1 = b1;
}
public:
__forceinline bool empty() const {
return bounds().empty();
}
__forceinline BBox<T> bounds () const {
return merge(bounds0,bounds1);
}
__forceinline BBox<T> interpolate( const float t ) const {
return lerp(bounds0,bounds1,t);
}
__forceinline LBBox<T> interpolate( const BBox1f& dt ) const {
return LBBox<T>(interpolate(dt.lower),interpolate(dt.upper));
}
__forceinline void extend( const LBBox& other ) {
bounds0.extend(other.bounds0);
bounds1.extend(other.bounds1);
}
__forceinline float expectedHalfArea() const;
__forceinline float expectedHalfArea(const BBox1f& dt) const {
return interpolate(dt).expectedHalfArea();
}
__forceinline float expectedApproxHalfArea() const {
return 0.5f*(halfArea(bounds0) + halfArea(bounds1));
}
/* calculates bounds for [0,1] time range from bounds in dt time range */
__forceinline LBBox global(const BBox1f& dt) const
{
const float rcp_dt_size = 1.0f/dt.size();
const BBox<T> b0 = interpolate(-dt.lower*rcp_dt_size);
const BBox<T> b1 = interpolate((1.0f-dt.lower)*rcp_dt_size);
return LBBox(b0,b1);
}
/*! Comparison Operators */
//template<typename TT> friend __forceinline bool operator==( const LBBox<TT>& a, const LBBox<TT>& b ) { return a.bounds0 == b.bounds0 && a.bounds1 == b.bounds1; }
//template<typename TT> friend __forceinline bool operator!=( const LBBox<TT>& a, const LBBox<TT>& b ) { return a.bounds0 != b.bounds0 || a.bounds1 != b.bounds1; }
friend __forceinline bool operator==( const LBBox& a, const LBBox& b ) { return a.bounds0 == b.bounds0 && a.bounds1 == b.bounds1; }
friend __forceinline bool operator!=( const LBBox& a, const LBBox& b ) { return a.bounds0 != b.bounds0 || a.bounds1 != b.bounds1; }
/*! output operator */
friend __forceinline embree_ostream operator<<(embree_ostream cout, const LBBox& box) {
return cout << "LBBox { " << box.bounds0 << "; " << box.bounds1 << " }";
}
public:
BBox<T> bounds0, bounds1;
};
/*! tests if box is finite */
template<typename T>
__forceinline bool isvalid( const LBBox<T>& v ) {
return isvalid(v.bounds0) && isvalid(v.bounds1);
}
template<typename T>
__forceinline bool isvalid_non_empty( const LBBox<T>& v ) {
return isvalid_non_empty(v.bounds0) && isvalid_non_empty(v.bounds1);
}
template<typename T>
__forceinline T expectedArea(const T& a0, const T& a1, const T& b0, const T& b1)
{
const T da = a1-a0;
const T db = b1-b0;
return a0*b0+(a0*db+da*b0)*T(0.5f) + da*db*T(1.0f/3.0f);
}
template<> __forceinline float LBBox<Vec3fa>::expectedHalfArea() const
{
const Vec3fa d0 = bounds0.size();
const Vec3fa d1 = bounds1.size();
return reduce_add(expectedArea(Vec3fa(d0.x,d0.y,d0.z),
Vec3fa(d1.x,d1.y,d1.z),
Vec3fa(d0.y,d0.z,d0.x),
Vec3fa(d1.y,d1.z,d1.x)));
}
template<typename T>
__forceinline float expectedApproxHalfArea(const LBBox<T>& box) {
return box.expectedApproxHalfArea();
}
template<typename T>
__forceinline LBBox<T> merge(const LBBox<T>& a, const LBBox<T>& b) {
return LBBox<T>(merge(a.bounds0, b.bounds0), merge(a.bounds1, b.bounds1));
}
/*! subset relation */
template<typename T> __inline bool subset( const LBBox<T>& a, const LBBox<T>& b ) {
return subset(a.bounds0,b.bounds0) && subset(a.bounds1,b.bounds1);
}
/*! default template instantiations */
typedef LBBox<float> LBBox1f;
typedef LBBox<Vec2f> LBBox2f;
typedef LBBox<Vec3f> LBBox3f;
typedef LBBox<Vec3fa> LBBox3fa;
typedef LBBox<Vec3fx> LBBox3fx;
}