test_area.cpp

// Description: Testing for area computations
// DocumentationOf: area.h

#include "test/test_init.h"

#include "pastel/geometry/area.h"
#include "pastel/sys/rational.h"

using Real = Rational<integer>;

TEST_CASE("BoxArea (area)")
{
    REQUIRE(
        absoluteError<real>(boxArea(Vector1(2)), 0) < 0.001);
    REQUIRE(
        relativeError<real>(boxArea(Vector2(2, 2)), 8) < 0.001);
    REQUIRE(
        relativeError<real>(boxArea(Vector2(3, 6)), 18) < 0.001);
    REQUIRE(
        relativeError<real>(boxArea(Vector2(6, 3)), 18) < 0.001);
    REQUIRE(
        relativeError<real>(boxArea(Vector2(0, 6)), 12) < 0.001);
    REQUIRE(
        relativeError<real>(boxArea(Vector2(6, 0)), 12) < 0.001);

    REQUIRE(
        relativeError<real>(boxArea(Vector3(1, 2, 3)), 22) < 0.001);
    REQUIRE(
        relativeError<real>(boxArea(Vector3(3, 2, 1)), 22) < 0.001);
    REQUIRE(
        relativeError<real>(boxArea(Vector3(2, 3, 1)), 22) < 0.001);
    REQUIRE(
        relativeError<real>(boxArea(Vector3(0, 2, 3)), 12) < 0.001);
    REQUIRE(
        absoluteError<real>(boxArea(Vector3(3, 0, 0)), 0) < 0.001);
    REQUIRE(
        absoluteError<real>(boxArea(Vector3(0, 3, 0)), 0) < 0.001);
    REQUIRE(
        absoluteError<real>(boxArea(Vector3(0, 0, 3)), 0) < 0.001);
}

TEST_CASE("PolygonArea (area)")
{
    /*
   {
       // Triangle
       Polygon<Real, 2> p;
       p.pushBack(Vector<Real, 2>(Real(0, 1), Real(0, 1)));
       p.pushBack(Vector<Real, 2>(Real(1, 1), Real(0, 1)));
       p.pushBack(Vector<Real, 2>(Real(1, 1), Real(2, 1)));

       REQUIRE(signedArea(p) == Real(1, 1));
   }
   {
       // Square
       Polygon<Real, 2> p;
       p.pushBack(Vector<Real, 2>(Real(0, 1), Real(0, 1)));
       p.pushBack(Vector<Real, 2>(Real(1, 1), Real(0, 1)));
       p.pushBack(Vector<Real, 2>(Real(1, 1), Real(1, 1)));
       p.pushBack(Vector<Real, 2>(Real(0, 1), Real(1, 1)));

       REQUIRE(signedArea(p) == Real(1, 1));
   }
   {
       // Reversed square
       Polygon<Real, 2> p;
       p.pushBack(Vector<Real, 2>(Real(0, 1), Real(0, 1)));
       p.pushBack(Vector<Real, 2>(Real(0, 1), Real(1, 1)));
       p.pushBack(Vector<Real, 2>(Real(1, 1), Real(1, 1)));
       p.pushBack(Vector<Real, 2>(Real(1, 1), Real(0, 1)));

       REQUIRE(signedArea(p) == Real(-1, 1));
   }
   {
       // Translated square
       Polygon<Real, 2> p;
       p.pushBack(Vector<Real, 2>(Real(0 + 2, 1), Real(0 - 3, 1)));
       p.pushBack(Vector<Real, 2>(Real(1 + 2, 1), Real(0 - 3, 1)));
       p.pushBack(Vector<Real, 2>(Real(1 + 2, 1), Real(1 - 3, 1)));
       p.pushBack(Vector<Real, 2>(Real(0 + 2, 1), Real(1 - 3, 1)));

       REQUIRE(signedArea(p) == Real(1, 1));
   }
   {
       // Six sided polygon.
       Polygon<Real, 2> p;
       p.pushBack(Vector<Real, 2>(Real(0, 1), Real(3, 1)));
       p.pushBack(Vector<Real, 2>(Real(2, 1), Real(2, 1)));
       p.pushBack(Vector<Real, 2>(Real(3, 1), Real(0, 1)));
       p.pushBack(Vector<Real, 2>(Real(2, 1), Real(-2, 1)));
       p.pushBack(Vector<Real, 2>(Real(0, 1), Real(-3, 1)));
       p.pushBack(Vector<Real, 2>(Real(-2, 1), Real(-2, 1)));
       p.pushBack(Vector<Real, 2>(Real(-3, 1), Real(0, 1)));
       p.pushBack(Vector<Real, 2>(Real(-2, 1), Real(2, 1)));

       REQUIRE(signedArea(p) == Real(24, 1));
   }
   {
       // Half of the six sided polygon.
       Polygon<Real, 2> p;
       p.pushBack(Vector<Real, 2>(Real(0, 1), Real(3, 1)));
       p.pushBack(Vector<Real, 2>(Real(2, 1), Real(2, 1)));
       p.pushBack(Vector<Real, 2>(Real(3, 1), Real(0, 1)));
       p.pushBack(Vector<Real, 2>(Real(2, 1), Real(-2, 1)));
       p.pushBack(Vector<Real, 2>(Real(0, 1), Real(-3, 1)));

       REQUIRE(signedArea(p) == Real(12, 1));
   }
   {
       // Quarter of the six sided polygon.
       Polygon<Real, 2> p;
       p.pushBack(Vector<Real, 2>(Real(0, 1), Real(3, 1)));
       p.pushBack(Vector<Real, 2>(Real(2, 1), Real(2, 1)));
       p.pushBack(Vector<Real, 2>(Real(3, 1), Real(0, 1)));

       REQUIRE(signedArea(p) == Real(6, 1));
   }
   {
       // Translated quarter of the six sided polygon.
       Polygon<Real, 2> p;
       p.pushBack(Vector<Real, 2>(Real(0 - 5, 1), Real(3 + 15, 1)));
       p.pushBack(Vector<Real, 2>(Real(2 - 5, 1), Real(2 + 15, 1)));
       p.pushBack(Vector<Real, 2>(Real(3 - 5, 1), Real(0 + 15, 1)));

       REQUIRE(signedArea(p) == Real(6, 1));
   }
   */
}