libcruft-util/region.cpp

304 lines
7.2 KiB
C++

/*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* Copyright 2010-2017 Danny Robson <danny@nerdcruft.net>
*/
#include "region.hpp"
#include "debug/assert.hpp"
#include "coord/iostream.hpp"
#include <array>
using cruft::region;
///////////////////////////////////////////////////////////////////////////////
template <size_t S, typename T>
typename cruft::region<S,T>::extent_t
cruft::region<S,T>::magnitude (void) const
{
return e;
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
typename cruft::region<S,T>::extent_t
cruft::region<S,T>::magnitude (extent_t _e)
{
e = _e;
return e;
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
bool
cruft::region<S,T>::empty (void) const
{
return almost_zero (area ());
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
typename cruft::region<S,T>::point_t
cruft::region<S,T>::base (void) const
{
return p;
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
typename cruft::region<S,T>::point_t
cruft::region<S,T>::away (void) const
{
return p + e;
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
typename cruft::region<S,T>::point_t
cruft::region<S,T>::centre (void) const
{
return p + e / T{2};
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
typename cruft::region<S,T>::point_t
cruft::region<S,T>::closest (point_t q) const
{
return clamp (q, p, p + e);
}
//-----------------------------------------------------------------------------
// FIXME: This will fail with an actual infinite range (NaNs will be generated
// in the conditionals).
template <size_t S, typename T>
bool
cruft::region<S,T>::intersects (region<S,T> rhs) const
{
for (size_t i = 0; i < S; ++i)
if ( p[i] >= rhs.p[i] + rhs.e[i] ||
rhs.p[i] >= p[i] + e[i])
{ return false; }
return true;
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
typename region<S,T>::point_t
region<S,T>::constrain (point_t q) const noexcept
{
return closest (q);
}
//-----------------------------------------------------------------------------
template<size_t S, typename T>
cruft::region<S,T>
cruft::region<S,T>::intersection (region<S,T> rhs) const
{
// find the intersection corners
point_t a, b;
for (size_t i = 0; i < S; ++i) {
a[i] = cruft::max (p[i], rhs.p[i]);
b[i] = cruft::min (p[i] + e[i], rhs.p[i] + rhs.e[i]);
if (b[i] < a[i])
throw std::logic_error ("no overlap");
}
return { a, b };
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
bool
cruft::region<S,T>::covers (region<S, T> r) const noexcept
{
return all (p <= r.p) && all (p + e >= r.p + r.e);
}
///////////////////////////////////////////////////////////////////////////////
template <size_t S, typename T>
cruft::region<S,T>
cruft::region<S,T>::inset (T mag) const
{
return inset (cruft::vector<S,T> {mag});
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
cruft::region<S,T>
cruft::region<S,T>::inset (vector<S,T> mag) const
{
// ensure we have enough space to trim off our total extent
CHECK (all (e >= T{2} * mag));
return {
p + mag,
e - T{2} * mag
};
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
cruft::region<S,T>
cruft::region<S,T>::expand (vector<S,T> v) const
{
return {
p - v,
e + v * T{2}
};
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
cruft::region<S,T>
cruft::region<S,T>::expand (T mag) const
{
return expand (vector<S,T> {mag});
}
///////////////////////////////////////////////////////////////////////////////
template <size_t S, typename T>
cruft::region<S,T>
cruft::region<S,T>::operator+ (vector<S,T> rhs) const
{
return { p + rhs, e };
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
cruft::region<S,T>
cruft::region<S,T>::operator- (vector<S,T> rhs) const
{
return { p - rhs, e };
}
///////////////////////////////////////////////////////////////////////////////
template <size_t S, typename T>
bool
cruft::region<S,T>::operator== (region rhs) const
{
return p == rhs.p && e == rhs.e;
}
///////////////////////////////////////////////////////////////////////////////
template <typename T>
cruft::region<2,T>
cruft::rotate90 (cruft::region<2,T> obj, int steps)
{
CHECK_INCLUSIVE (steps, 0, 3);
switch (steps) {
case 0:
return obj;
case 1:
return region2<T> {
point2<T> {
T(obj.p.x - obj.e.h),
obj.p.y
},
extent2<T> {
obj.e.h,
obj.e.w,
}
};
case 2:
return region2<T> {
point2<T> {
obj.p.x,
T(obj.p.y - obj.e.h),
},
obj.e,
};
case 3:
return region2<T> {
obj.p,
extent2<T> {
obj.e.h,
obj.e.w,
},
};
}
unreachable();
}
//-----------------------------------------------------------------------------
template cruft::region2<i32> cruft::rotate90 (cruft::region2<i32>, int);
template cruft::region2<i64> cruft::rotate90 (cruft::region2<i64>, int);
template cruft::region2<f32> cruft::rotate90 (cruft::region2<f32>, int);
///////////////////////////////////////////////////////////////////////////////
template <size_t S, typename T>
std::ostream&
cruft::operator<< (std::ostream &os, const cruft::region<S,T> &rhs) {
return os << "{ position: " << rhs.p << ", extent: " << rhs.e << " }";
}
///////////////////////////////////////////////////////////////////////////////
namespace cruft::debug {
template <size_t S, typename T>
struct validator<cruft::region<S,T>> {
static bool is_valid (const cruft::region<S,T> &r)
{
return cruft::debug::is_valid (r.p) && cruft::debug::is_valid (r.e);
}
};
}
///////////////////////////////////////////////////////////////////////////////
#define INSTANTIATE_S_T(S,T) \
template struct cruft::region<S,T>; \
template std::ostream& cruft::operator<< (std::ostream&, const region<S,T>&); \
template struct cruft::debug::validator<cruft::region<S,T>>;
#define INSTANTIATE(T) \
INSTANTIATE_S_T(2,T) \
INSTANTIATE_S_T(3,T)
INSTANTIATE(i16);
INSTANTIATE(i32);
INSTANTIATE(i64);
INSTANTIATE(u16)
INSTANTIATE(u32)
INSTANTIATE(u64)
INSTANTIATE(f32)
INSTANTIATE(f64)