#include <math/dvc_math_util.h>
#include <math/dvc_matrix4.h>
#include <math/dvc_vector3.h>
#include <math/dvc_vector4.h>

#include <gtest/gtest.h>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>

#include "dvt_unit_common.h"

using namespace davinci;

//-------------------------------------------------------------------------------------
TEST(MathUtil, Basic)
{

	//lookat view matrix
	{
		float dEye[3] = { 0.0f, 4.0f, -10.0f };
		float dAt[3] = { 0.0f, 1.0f, 0.0f };
		float dUp[3] = { 0.0f, 1.0f, 0.0f };

		fMatrix4 m1 = MathUtil::lookatRH(
			fVector3(THREE_ELEMENT(dEye)),
			fVector3(THREE_ELEMENT(dAt)),
			fVector3(THREE_ELEMENT(dUp)));

		glm::mat4 gm1 = glm::lookAtRH(glm::vec3(THREE_ELEMENT(dEye)), glm::vec3(THREE_ELEMENT(dAt)), glm::vec3(THREE_ELEMENT(dUp)));
		EXPECT_EQ_4X4_T(m1, gm1);
	}

	//lookat view matrix(random)
	{
		for (int i = 0; i < 10; i++) {
			fVector3 dEye, dAt, dUp;
			do {
				dEye[0] = _randomFloat(); dEye[1] = _randomFloat(); dEye[2] = _randomFloat();
				dAt[0] = _randomFloat(); dAt[1] = _randomFloat(); dAt[2] = _randomFloat();
				dUp[0] = _randomFloat(); dUp[1] = _randomFloat(); dUp[2] = _randomFloat();

			} while ((dEye == dAt) || (dUp == fVector3::ZERO));

			fMatrix4 m1 = MathUtil::lookatRH(
				fVector3(THREE_ELEMENT(dEye)),
				fVector3(THREE_ELEMENT(dAt)),
				fVector3(THREE_ELEMENT(dUp)));

			glm::mat4 gm1 = glm::lookAtRH(glm::vec3(THREE_ELEMENT(dEye)), glm::vec3(THREE_ELEMENT(dAt)), glm::vec3(THREE_ELEMENT(dUp)));

			EXPECT_EQ_4X4_T_APPROX(m1, gm1, std::numeric_limits<float>::epsilon() * 1000);
		}
	}

	//perspective
	{
		float width = 640.f, height = 480.f;

		fMatrix4 m1 = MathUtil::perspectiveFovRH(MathUtil::PI_DIV4, width / height, 0.01f, 100.f);
		glm::mat4 gm1 = glm::perspectiveRH(MathUtil::PI_DIV4, width / height, 0.01f, 100.f);

		EXPECT_EQ_4X4_T_APPROX(m1, gm1, std::numeric_limits<float>::epsilon());
	}

	//perspective(random)
	{
		for (int i = 0; i < 10; i++) {
			float fov = MathUtil::rangeRandom(0.1f, MathUtil::PI);
			float aspect = MathUtil::rangeRandom(0.1f, 100.f);
			float zNear = MathUtil::rangeRandom(0.00001f, 0.01f);
			float zFar = MathUtil::rangeRandom(100.f, 10000.f);

			fMatrix4 m1 = MathUtil::perspectiveFovRH(fov, aspect, zNear, zFar);
			glm::mat4 gm1 = glm::perspectiveRH(fov, aspect, zNear, zFar);

			EXPECT_EQ_4X4_T_APPROX(m1, gm1, std::numeric_limits<float>::epsilon() * 100);
		}
	}
}