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#include "common.hpp"
#include <fpm/math.hpp>
TEST(trigonometry, sin)
{
using P = fpm::fixed<std::int32_t, std::int64_t, 16>;
const double PI = std::acos(-1);
constexpr auto MAX_ERROR_PERC = 0.002;
for (int angle = -1799; angle <= 1800; ++angle)
{
auto flt_angle = angle * PI / 180;
auto sin_real = std::sin(flt_angle);
auto sin_fixed = static_cast<double>(sin(P(flt_angle)));
EXPECT_TRUE(HasMaximumError(sin_fixed, sin_real, MAX_ERROR_PERC));
}
}
TEST(trigonometry, cos)
{
using P = fpm::fixed<std::int32_t, std::int64_t, 16>;
const double PI = std::acos(-1);
constexpr auto MAX_ERROR_PERC = 0.002;
for (int angle = -1799; angle <= 1800; ++angle)
{
auto flt_angle = angle * PI / 180;
auto cos_real = std::cos(flt_angle);
auto cos_fixed = static_cast<double>(cos(P(flt_angle)));
EXPECT_TRUE(HasMaximumError(cos_fixed, cos_real, MAX_ERROR_PERC));
}
}
TEST(trigonometry, tan)
{
using P = fpm::fixed<std::int32_t, std::int64_t, 16>;
const double PI = std::acos(-1);
constexpr auto MAX_ERROR_PERC = 0.002;
for (int angle = -1799; angle <= 1800; ++angle)
{
// Tangent goes to infinite at 90 and -90 degrees.
// We can't represent that with fixed-point maths, so don't test for it.
if ((angle + 90) % 180 != 0)
{
auto flt_angle = angle * PI / 180;
auto tan_real = std::tan(flt_angle);
auto tan_fixed = static_cast<double>(tan(P(flt_angle)));
EXPECT_TRUE(HasMaximumError(tan_fixed, tan_real, MAX_ERROR_PERC));
}
}
#ifndef NDEBUG
EXPECT_DEATH(tan(P::pi()/2), "");
EXPECT_DEATH(tan(-P::pi()/2), "");
#endif
}
TEST(trigonometry, atan)
{
using P = fpm::fixed<std::int32_t, std::int64_t, 12>;
constexpr auto MAX_ERROR_PERC = 0.025;
for (int x = -1000; x <= 1000; ++x)
{
auto value = x / 10.0;
auto atan_real = std::atan(value);
auto atan_fixed = static_cast<double>(atan(P(value)));
EXPECT_TRUE(HasMaximumError(atan_fixed, atan_real, MAX_ERROR_PERC));
}
for (int x = -1000; x <= 1000; ++x)
{
auto value = x / 1000.0;
auto atan_real = std::atan(value);
auto atan_fixed = static_cast<double>(atan(P(value)));
EXPECT_TRUE(HasMaximumError(atan_fixed, atan_real, MAX_ERROR_PERC));
}
}
TEST(trigonometry, asin)
{
using P = fpm::fixed<std::int32_t, std::int64_t, 12>;
constexpr auto MAX_ERROR_PERC = 0.025;
for (int x = -1000; x <= 1000; ++x)
{
auto value = x / 1000.0;
auto asin_real = std::asin(value);
auto asin_fixed = static_cast<double>(asin(P(value)));
EXPECT_TRUE(HasMaximumError(asin_fixed, asin_real, MAX_ERROR_PERC));
}
}
TEST(trigonometry, acos)
{
using P = fpm::fixed<std::int32_t, std::int64_t, 12>;
constexpr auto MAX_ERROR_PERC = 0.025;
for (int x = -1000; x <= 1000; ++x)
{
auto value = x / 1000.0;
auto acos_real = std::acos(value);
auto acos_fixed = static_cast<double>(acos(P(value)));
EXPECT_TRUE(HasMaximumError(acos_fixed, acos_real, MAX_ERROR_PERC));
}
}
TEST(trigonometry, atan2)
{
using P = fpm::fixed<std::int32_t, std::int64_t, 12>;
const double PI = std::acos(-1);
constexpr auto MAX_ERROR_PERC = 0.025;
for (int angle = -1799; angle <= 1800; ++angle)
{
const auto y = std::sin(angle * PI / 1800);
const auto x = std::cos(angle * PI / 1800);
auto atan2_real = std::atan2(y, x);
auto atan2_fixed = static_cast<double>(atan2(P(y), P(x)));
EXPECT_TRUE(HasMaximumError(atan2_fixed, atan2_real, MAX_ERROR_PERC));
}
#ifndef NDEBUG
EXPECT_DEATH(atan2(P(0), P(0)), "");
#endif
}
// Naively, atan2(y, x) does y / x which would overflow for near-zero x with Q16.16.
// Test that we've got protections in place for this.
TEST(trigonometry, atan2_near_zero)
{
constexpr auto MAX_ERROR_PERC = 0.025;
using P = fpm::fixed_16_16;
const auto x = P::from_raw_value(1);
const auto y = P(100);
// Positive x
{
auto atan2_real = std::atan2(static_cast<double>(y), static_cast<double>(x));
auto atan2_fixed = static_cast<double>(atan2(y, x));
EXPECT_TRUE(HasMaximumError(atan2_fixed, atan2_real, MAX_ERROR_PERC));
}
// Negative x
{
auto atan2_real = std::atan2(static_cast<double>(y), static_cast<double>(-x));
auto atan2_fixed = static_cast<double>(atan2(y, -x));
EXPECT_TRUE(HasMaximumError(atan2_fixed, atan2_real, MAX_ERROR_PERC));
}
}
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