libcruft-util/test/region.cpp

291 lines
9.1 KiB
C++

#include "region.hpp"
#include "point.hpp"
#include "tap.hpp"
#include <vector>
//-----------------------------------------------------------------------------
int
main (int, char **)
{
cruft::TAP::logger tap;
// check that two overlapping regions successfully test for intersection
{
const cruft::point2d ap { 32.7, -6.09703 };
const cruft::extent2d ae { 0.8, 2. };
const cruft::region2d a (ap, ae);
const cruft::point2d bp {33.5, -4.5};
const cruft::extent2d be { 0.5, 0.5 };
const cruft::region2d b (bp, be);
tap.expect (!a.intersects (b), "simple 2d intersection");
}
{
using p_t = cruft::point2i;
using e_t = cruft::extent2i;
struct {
cruft::region2i a;
cruft::region2i b;
bool intersection;
char const *message;
} const TESTS[] = {
{
.a = { p_t { 58, 22 }, e_t { 13, 8 } },
.b = { p_t { 58, 22 }, e_t { 7, 7 } },
.intersection = true,
.message = "Coaligned base",
},
{
.a = { p_t { 21, 32 }, e_t { 13, 8 } },
.b = { p_t { 27, 33 }, e_t { 24, 24 } },
.intersection = true,
.message = "corner overlap",
}
};
for (auto const &[a, b, res, msg]: TESTS) {
tap.expect_eq (a.intersects (b), res, "intersection a-on-b: {}", msg);
tap.expect_eq (b.intersects (a), res, "intersection b-on-a: {}", msg);
}
}
// check various floating point maximums successfully test for
// intersection. the concern is that infinities are incorrectly handled
// in some comparisons.
tap.expect (
cruft::region2d::max ().intersects (
cruft::region2d::unit ()
),
"maximal region2d intersection"
);
tap.expect (
cruft::region2f::max ().intersects (
cruft::region2f::unit ()
),
"maximal region2f intersection"
);
// ensure unit regions are... unit sized...
tap.expect_eq (cruft::region2d::unit ().area (), 1.0, "unit region2d area");
tap.expect_eq (cruft::region2f::unit ().area (), 1.0f, "unit region2f area");
// test boundary cases of includes and contains
{
const cruft::point2f p0 { 0 };
const cruft::extent2f e0 { 2 };
const cruft::region2f r {p0, e0};
tap.expect (!r.inclusive (cruft::point2f {-1, 1}), "region/point inclusive, invalid x");
tap.expect (!r.inclusive (cruft::point2f { 1, 3}), "region/point inclusive, invalid y ");
tap.expect (r.inclusive (cruft::point2f {1, 1}), "region/point inclusive, centre");
tap.expect (r.inclusive (cruft::point2f {0, 0}), "region/point inclusive, base");
tap.expect (r.inclusive (cruft::point2f {2, 2}), "region/point inclusive, corner");
}
// ensure union operator behaves as expected
{
const cruft::point2f p { -1 };
const cruft::extent2f e { 2 };
const cruft::region2f r { p, e };
tap.expect_eq (r | cruft::point2f { 0, 0 }, r, "identity union");
tap.expect_eq (
r | cruft::point2f { 2, 3 },
cruft::region2f { p, cruft::extent2f { 3, 4 } },
"positive expanding union"
);
tap.expect_eq (
r | cruft::point2f { -3, -2 },
cruft::region2f {
cruft::point2f { -3, -2 },
cruft::extent2f { 4, 3 }
},
"negative expanding union"
);
};
// Check that 'covers' behaves as expected. ie, a covers b.
{
using p = cruft::point2i;
using e = cruft::extent2i;
struct {
cruft::region2i a;
cruft::region2i b;
bool expected;
char const *message;
} TESTS[] = {
{
.a = { p { 0, 0, }, e { 32, 32, } },
.b = { p { 27, 4, }, e { 8, 13, } },
.expected = false,
.message = "a exceeds +x margin",
}
};
for (auto const &[a, b, expected, msg]: TESTS)
tap.expect_eq (a.covers (b), expected, "covers: {}", msg);
}
// ensure make_region covers the expected values
{
const cruft::region2i REGION {
cruft::point2i { 0, 0 },
cruft::point2i { 3, 2 }
};
const cruft::point2i EXPECTED[] = {
{ 0, 0 }, { 1, 0 }, { 2, 0 },
{ 0, 1 }, { 1, 1 }, { 2, 1 },
};
std::vector<cruft::point2i> values;
std::copy (std::cbegin (REGION.step ()), std::cend (REGION.step ()), std::back_inserter (values));
bool success = values.size () == std::size (EXPECTED)
&& std::equal (std::cbegin (values), std::cend (values),
std::cbegin (EXPECTED), std::cend (EXPECTED));
tap.expect (success, "make_range(region2i)");
};
// test distance2 for points
{
struct {
cruft::region2f r;
cruft::point2f p;
float distance2;
char const *message;
} const TESTS[] = {
{
{ cruft::point2f { 1, 1 }, cruft::point2f { 3, 5 } },
{ 0, 0 },
2.f,
"origin to offset rect"
},
{
{ cruft::point2f { 1, 1 }, cruft::point2f { 3, 5 } },
{ 2, 2 },
0.f,
"point inside region"
},
{
{ cruft::point2f { 1, 1 }, cruft::point2f { 3, 5 } },
{ 4, 7 },
1 + 4,
"offset point to offset rect"
},
};
for (auto const &t: TESTS) {
auto const d2 = distance2 (t.r, t.p);
tap.expect_eq (d2, t.distance2, "region-point distance2: {}", t.message);
}
};
// Test expected results of 2 region interesection
{
using p_t = cruft::point2i;
struct {
cruft::region2i a;
cruft::region2i b;
cruft::region2i res;
char const *msg;
} const TESTS[] = {
{
.a = { p_t { 0, 0 }, p_t { 1, 1 } },
.b = { p_t { 0, 0 }, p_t { 1, 1 } },
.res = { p_t { 0, 0 }, p_t { 1, 1 } },
.msg = "identical, unit sizes",
},
{
.a = { p_t { 0, 0 }, p_t { 1, 1 } },
.b = { p_t { 1, 1 }, p_t { 2, 2 } },
.res = { p_t { 1, 1 }, p_t { 1, 1 } },
.msg = "unit sized, shared corner",
},
{
.a = { p_t { -4, -5 }, p_t { 5, 3 } },
.b = { p_t { -1, -2 }, p_t { 2, 1 } },
.res = { p_t { -1, -2 }, p_t { 2, 1 } },
.msg = "a contains b",
},
{
.a = { p_t { -1, -2 }, p_t { 2, 1 } },
.b = { p_t { -4, -5 }, p_t { 5, 3 } },
.res = { p_t { -1, -2 }, p_t { 2, 1 } },
.msg = "b contains a",
},
{
.a = { p_t { -3, -1 }, p_t { 4, 8 } },
.b = { p_t { -1, -4 }, p_t { 6, 2 } },
.res = { p_t { -1, -1 }, p_t { 4, 2 } },
.msg = "partial overlap",
},
};
for (auto const &[a, b, res, message]: TESTS)
tap.expect_eq (intersection (a, b), res, "region-region interesection: {}", message);
}
// Test rotate behaves as expected.
//
// It's important that the following constraints apply to the test data:
// * no point lies at the origin because we want to catch
// rotate-about-point errors that need a translation.
// * the size is non-square so we can differentiate between rotated
// values
// * use floating point values so we can test for loss of precision.
{
cruft::point2f const base { 1, 2 };
cruft::extent2f const size { 3, 4 };
cruft::region2f const orig { base, size };
struct {
int rotation;
cruft::region2f res;
} const TESTS[] {
{
.rotation = 0,
.res = orig,
},
{
.rotation = 1,
.res = {
cruft::point2f { -3, 2 },
cruft::extent2f { 4, 3 },
},
},
{
.rotation = 2,
.res = {
cruft::point2f { 1, -2 },
cruft::extent2f { 3, 4 },
},
},
{
.rotation = 3,
.res = {
cruft::point2f { 1, 2 },
cruft::extent2f { 4, 3 },
},
}
};
for (auto const &obj: TESTS) {
auto const computed = rotate90 (orig, obj.rotation);
tap.expect_eq (computed, obj.res, "{} rotation", obj.rotation);
}
}
return tap.status ();
}