India/cocos2d-x/extensions/Particle3D/PU/CCPUUtil.cpp

/****************************************************************************
 Copyright (C) 2013 Henry van Merode. All rights reserved.
 Copyright (c) 2015-2016 Chukong Technologies Inc.
 Copyright (c) 2017-2018 Xiamen Yaji Software Co., Ltd.
 
 http://www.cocos2d-x.org
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
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 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.
 
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 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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#include "CCPUUtil.h"
#include "base/ccMacros.h"

NS_CC_BEGIN

cocos2d::Vec3 PUUtil::randomDeviant( const Vec3 &src, float angle, const Vec3& up /*= Vec3::ZERO*/ )
{
    Vec3 newUp;

    if (up == Vec3::ZERO)
    {
        // Generate an up vector
        newUp = perpendicular(src);
    }
    else
    {
        newUp = up;
    }

    // Rotate up vector by random amount around this
    //Quaternion q;
    //q.FromAngleAxis( Radian(Math::UnitRandom() * Math::TWO_PI), *this );
    //newUp = q * newUp;

    //// Finally rotate this by given angle around randomised up
    //q.FromAngleAxis( angle, newUp );
    //return q * (*this);

	Quaternion q;
	Mat4 mat;
	Quaternion::createFromAxisAngle(src, CCRANDOM_0_1() * M_PI * 2.0f, &q);
    Mat4::createRotation(q, &mat);

	//{
	//	Vec3 uv, uuv;
	//	Vec3 qvec(q.x, q.y, q.z);
	//	Vec3::cross(qvec, newUp, &uv);
	//	Vec3::cross(qvec, uv, &uuv);
	//	uv *= (2.0f * q.w);
	//	uuv *= 2.0f;
	//	newUp = newUp + uv + uuv;
	//}

    newUp = mat * newUp;
	Quaternion::createFromAxisAngle(newUp, angle, &q);
    Mat4::createRotation(q, &mat);
    return  mat * src;

	//{
	//	Vec3 uv, uuv;
	//	Vec3 qvec(q.x, q.y, q.z);
	//	Vec3::cross(qvec, src, &uv);
	//	Vec3::cross(qvec, uv, &uuv);
	//	uv *= (2.0f * q.w);
	//	uuv *= 2.0f;
	//	return src + uv + uuv;
	//}
}

cocos2d::Vec3 PUUtil::perpendicular( const Vec3 &src )
{
    //static const float fSquareZero = (float)(1e-06 * 1e-06);

    //Vector3 perp = this->crossProduct( Vector3::UNIT_X );

    //// Check length
    //if( perp.squaredLength() < fSquareZero )
    //{
    //	/* This vector is the Y axis multiplied by a scalar, so we have
    //		to use another axis.
    //	*/
    //	perp = this->crossProduct( Vector3::UNIT_Y );
    //}
    //perp.normalise();

    //return perp;

    static const float fSquareZero = (float)(1e-06 * 1e-06);
    Vec3 perp;
    Vec3::cross(src, Vec3::UNIT_X, &perp);
    // Check length
    if( perp.lengthSquared() < fSquareZero )
    {
        /* This vector is the Y axis multiplied by a scalar, so we have
            to use another axis.
        */
        Vec3::cross(src, Vec3::UNIT_Y, &perp);
    }
    perp.normalize();
    return perp;
}

NS_CC_END