// Copyright (C) 2015 Jérôme Leclercq
// This file is part of the "Nazara Engine - Physics 2D module"
// For conditions of distribution and use, see copyright notice in Config.hpp

#include <Nazara/Physics2D/PhysWorld2D.hpp>
#include <chipmunk/chipmunk.h>
#include <Nazara/Physics2D/Debug.hpp>

namespace Nz
{
	PhysWorld2D::PhysWorld2D() :
	m_stepSize(0.005f),
	m_timestepAccumulator(0.f)
	{
		m_handle = cpSpaceNew();
		cpSpaceSetUserData(m_handle, this);
	}

	PhysWorld2D::~PhysWorld2D()
	{
		cpSpaceFree(m_handle);
	}

	Vector2f PhysWorld2D::GetGravity() const
	{
		cpVect gravity = cpSpaceGetGravity(m_handle);
		return Vector2f(gravity.x, gravity.y);
	}

	cpSpace* PhysWorld2D::GetHandle() const
	{
		return m_handle;
	}

	float PhysWorld2D::GetStepSize() const
	{
		return m_stepSize;
	}

	void PhysWorld2D::SetGravity(const Vector2f& gravity)
	{
		cpSpaceSetGravity(m_handle, cpv(gravity.x, gravity.y));
	}

	void PhysWorld2D::SetStepSize(float stepSize)
	{
		m_stepSize = stepSize;
	}

	void PhysWorld2D::Step(float timestep)
	{
		m_timestepAccumulator += timestep;

		while (m_timestepAccumulator >= m_stepSize)
		{
			cpSpaceStep(m_handle, m_stepSize);
			m_timestepAccumulator -= m_stepSize;
		}
	}
}