genesis-3d_engine/Engine/addons/particles/affectors/particleGravityAffector.cc

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Copyright (c) 2011-2013,WebJet Business Division,CYOU

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#include "stdneb.h"
#include "particleGravityAffector.h"
#include "particles/particleaffector.h"
#include "particles/particlesystem.h"
#include "particles/particle.h"

namespace Particles
{
	using namespace Math;

	__ImplementClass(Particles::GravityAffector, CPFCC::AFFECTOR_GRAVITY, Particles::ParticleAffector);

	const Math::scalar GravityAffector::DEFAULT_GRAVITY = 1.0f;
	const Math::scalar GravityAffector::GRAVITY_MASS = 30.0f;
	//-----------------------------------------------------------------------
	GravityAffector::GravityAffector() : ParticleAffector()
	{
		mAffectType = AT_Gravity;
		mName = "GravityAffector";
	}
	//-----------------------------------------------------------------------
	void GravityAffector::_affect(Particle* particle)
	{		
		if(!GetEnable())
			return;
		float percent = particle->mTimeFraction;

		Math::float3	gravityDir(mMinMaxPosX.Calculate(percent,particle->mRandom0)
			, mMinMaxPosY.Calculate(percent,particle->mRandom1)
			, mMinMaxPosZ.Calculate(percent,particle->mRandom2)  );

		gravityDir = gravityDir - particle->mPosition;

		gravityDir.normalise();

		float  gravity = mMinMaxGravity.Calculate(percent,particle->mRandom3);

		Math::scalar _curTime = (Math::scalar)mParentSystem->GetCurrentFrameTime();
		particle->mDirection += gravity  * gravityDir * _curTime;

	}
	//-------------------------------------------------------------------------------
	void GravityAffector::InitShaderParam()
	{
		mShaderParam.x() = mMinMaxPosX.Calculate(0,Math::n_rand(0,1));
		mShaderParam.y() = mMinMaxPosY.Calculate(0,Math::n_rand(0,1));
		mShaderParam.z() = mMinMaxPosZ.Calculate(0,Math::n_rand(0,1));
		mShaderParam.w() = mMinMaxGravity.Calculate(0,Math::n_rand(0,1));
	}
	void GravityAffector::SetShaderParam()
	{
		Graphic::GlobalMaterialParam* pGMP = Graphic::Material::GetGlobalMaterialParams();
		pGMP->SetVectorParam(Graphic::eGShaderParticleGravity,mShaderParam);
	}
	//--------------------------------------------------------------------------------
	void GravityAffector::SetShaderMask(const GPtr<ShaderProgramCompiler::ShaderMarcro>& pMarcro)
	{
		if(!GetEnable())
			return;
		pMarcro->TurnOn(ShaderProgramCompiler::ShaderMarcro::m_sParticleGravity);
	}
	//--------------------------------------------------------------------------------
	Math::MinMaxCurve* GravityAffector::getMinMaxCurve(ParticleCurveType pct)
	{
		switch(pct)
		{
		case 	Affector_GravityX:
			return &mMinMaxPosX;
		case 	Affector_GravityY:
			return &mMinMaxPosY;
		case 	Affector_GravityZ:
			return &mMinMaxPosZ;
		case 	Affector_Gravity:
			return &mMinMaxGravity;
		default:
			return NULL;					
		}
	}
	//------------------------------------------------------------------------------------
	void GravityAffector::SwitchParticleType(bool _isMobile)
	{

	}
}