src/helper/units-test.h

	units-test.h revision 9cf82ac568634e779873c4bf6cd6b7bdd465556d
#include <cxxtest/TestSuite.h>

#include <helper/units.h>
#include <glibmm/i18n.h>
#include <math.h>

class UnitsTest : public CxxTest::TestSuite {
public:

    UnitsTest()
    {
    }
    virtual ~UnitsTest() {}

// createSuite and destroySuite get us per-suite setup and teardown
// without us having to worry about static initialization order, etc.
    static UnitsTest *createSuite() { return new UnitsTest(); }
    static void destroySuite( UnitsTest *suite ) { delete suite; }

    void testConversions()
    {
        struct Case { double x; char const *abbr; double pts; } const tests[] = {
            { 1.0, "pt", 1.0 },
            { 5.0, "pt", 5.0 },
            { 1.0, "in", 72.0 },
            { 2.0, "in", 144.0 },
            { 254., "mm", 720.0 },
            { 254., "cm", 7200. },
            { 254., "m", 720000. },
            { 1.5, "mm", (15 * 72. / 254) }
        };
        for (unsigned i = 0; i < G_N_ELEMENTS(tests); ++i) {
            Case const &c = tests[i];
            SPUnit const &unit = *sp_unit_get_by_abbreviation(N_(c.abbr));

            double const calc_pts = sp_units_get_points(c.x, unit);
            TS_ASSERT(approx_equal(calc_pts, c.pts));

            double const calc_x = sp_points_get_units(c.pts, unit);
            TS_ASSERT(approx_equal(calc_x, c.x));

            double tmp = c.x;
            bool const converted_to_pts = sp_convert_distance(&tmp, &unit, SP_PS_UNIT);
            TS_ASSERT(converted_to_pts);
            TS_ASSERT(approx_equal(tmp, c.pts));

            tmp = c.pts;
            bool const converted_from_pts = sp_convert_distance(&tmp, SP_PS_UNIT, &unit);
            TS_ASSERT(converted_from_pts);
            TS_ASSERT(approx_equal(tmp, c.x));
        }
    }

    void testUnitTable()
    {
        TS_ASSERT(sp_units_table_sane());
    }

private:
    /* N.B. Wrongly returns false if both near 0.  (Not a problem for current users.) */
    bool approx_equal(double const x, double const y)
    {
        return fabs(x / y - 1) < 1e-15;
    }

    double sp_units_get_points(double const x, SPUnit const &unit)
    {
        SPUnit const &pt_unit = sp_unit_get_by_id(SP_UNIT_PT);
        double const px = sp_units_get_pixels(x, unit);
        return sp_pixels_get_units(px, pt_unit);
    }

    double sp_points_get_units(double const pts, SPUnit const &unit)
    {
        SPUnit const &pt_unit = sp_unit_get_by_id(SP_UNIT_PT);
        double const px = sp_units_get_pixels(pts, pt_unit);
        return sp_pixels_get_units(px, unit);
    }
};

/*
  Local Variables:
  mode:c++
  c-file-style:"stroustrup"
  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
  indent-tabs-mode:nil
  fill-column:99
  End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :encoding=utf-8:textwidth=99 :