cocos2dx 3.3 操作节点相机

cocos2dx 3.3 操作节点相机：

　 CCSize winSize=CCDirector::sharedDirector()->getWinSize();

Camera* camera=Camera::create();

camera->setCameraFlag(CameraFlag::USER1);

this->addChild(camera);

sprite->setCameraMask(2);    //CameraFlag::USER1就等于2

Vec3 eyePosOld=camera->getPosition3D();

Vec3 eyePos=Vec3(0,0,eyePosOld.z);

camera->setPosition3D(eyePos);

camera->lookAt(Vec3(eyePos.x,eyePos.y,0), Vec3(0, 1, 0));//如果up参数传Vec3(sqrt(2)/2,sqrt(2)/2,0)可将头歪45度

注意camera->lookAt必须在camera->setPostion3D之后，因为lookAt中有一句

Vec3::subtract(this->getPosition3D(), lookAtPos, &zaxis);//即相减得出相机空间z轴

使用了getPosition3D。所以必须先设定对position3D再调lookAt才能得到正确结果。

参考：

http://www.cocos2d-x.org/news/344

cocos2d_tests - Camera3DTest.cpp