virtualx-engine/thirdparty/embree/kernels/subdiv/gridrange.h
2021-01-14 18:02:07 +01:00

96 lines
2.2 KiB
C++

// Copyright 2009-2020 Intel Corporation
// SPDX-License-Identifier: Apache-2.0
#pragma once
#include "../common/default.h"
namespace embree
{
struct __aligned(16) GridRange
{
unsigned int u_start;
unsigned int u_end;
unsigned int v_start;
unsigned int v_end;
__forceinline GridRange() {}
__forceinline GridRange(unsigned int u_start, unsigned int u_end, unsigned int v_start, unsigned int v_end)
: u_start(u_start), u_end(u_end), v_start(v_start), v_end(v_end) {}
__forceinline unsigned int width() const {
return u_end-u_start+1;
}
__forceinline unsigned int height() const {
return v_end-v_start+1;
}
__forceinline bool hasLeafSize() const
{
const unsigned int u_size = u_end-u_start+1;
const unsigned int v_size = v_end-v_start+1;
assert(u_size >= 1);
assert(v_size >= 1);
return u_size <= 3 && v_size <= 3;
}
static __forceinline unsigned int split(unsigned int start,unsigned int end)
{
const unsigned int center = (start+end)/2;
assert (center > start);
assert (center < end);
return center;
}
__forceinline void split(GridRange& r0, GridRange& r1) const
{
assert( hasLeafSize() == false );
const unsigned int u_size = u_end-u_start+1;
const unsigned int v_size = v_end-v_start+1;
r0 = *this;
r1 = *this;
if (u_size >= v_size)
{
const unsigned int u_mid = split(u_start,u_end);
r0.u_end = u_mid;
r1.u_start = u_mid;
}
else
{
const unsigned int v_mid = split(v_start,v_end);
r0.v_end = v_mid;
r1.v_start = v_mid;
}
}
__forceinline unsigned int splitIntoSubRanges(GridRange r[4]) const
{
assert( !hasLeafSize() );
unsigned int children = 0;
GridRange first,second;
split(first,second);
if (first.hasLeafSize()) {
r[0] = first;
children++;
}
else {
first.split(r[0],r[1]);
children += 2;
}
if (second.hasLeafSize()) {
r[children] = second;
children++;
}
else {
second.split(r[children+0],r[children+1]);
children += 2;
}
return children;
}
};
}