我正在尝试动态移动加载的对象,但要做到这一点,我需要获得该特定对象的4x4矩阵。
在下面的代码中,我将粪坑和奶牛模型加载到场景中,并且只想旋转奶牛模型。
我正在根据Openscenegraph 3.0初学者指南第234页中的"驾驶塞斯纳"示例尝试此练习。
注意:-这里已经生成了树。在没有更改树的情况下,用户需要使用导航键旋转所选对象。用户将使用鼠标选择所需的对象
#include <osg/MatrixTransform>
#include <osgDB/ReadFile>
#include <osgGA/GUIEventHandler>
#include <osgViewer/Viewer>
#include <osgViewer/ViewerEventHandlers>
#include <osg/io_utils>
osg::ref_ptr<osg::Group> root = new osg::Group;
class ModelController : public osgGA::GUIEventHandler
{
public:
ModelController( osg::MatrixTransform* node )
: _model(node)
{}
virtual bool handle( const osgGA::GUIEventAdapter& ea,
osgGA::GUIActionAdapter& aa );
protected:
osg::ref_ptr<osg::MatrixTransform> _model;
};
bool ModelController::handle( const osgGA::GUIEventAdapter& ea,
osgGA::GUIActionAdapter& aa )
{
if ( !_model )
{
std::cout<<"Not MODEL"<<std::endl;
return false;
}
osg::Matrix matrix = _model->getMatrix();
std::cout<<"MATRIX+"<<_model->getMatrix()<<std::endl;
switch ( ea.getEventType() )
{
case osgGA::GUIEventAdapter::KEYDOWN:
switch ( ea.getKey() )
{
case 'a': case 'A':
matrix *= osg::Matrix::rotate(-0.1f, osg::Z_AXIS);
break;
case 'd': case 'D':
matrix *= osg::Matrix::rotate(0.1f, osg::Z_AXIS);
break;
case 'w': case 'W':
matrix *= osg::Matrix::rotate(-0.1f, osg::X_AXIS);
break;
case 's': case 'S':
matrix *= osg::Matrix::rotate(0.1f, osg::X_AXIS);
break;
default:
break;
}
_model->setMatrix( matrix );
break;
default:
break;
}
return false;
}
int main(int argc,char *argv[])
{
osg::ref_ptr<osg::Node> model = osgDB::readNodeFile( "cessna.osg");
osg::ref_ptr<osg::Node> model1 = osgDB::readNodeFile( "cow.osg");
osg::ref_ptr<osg::MatrixTransform> mt = new osg::MatrixTransform;
mt->addChild( model.get() );
mt->addChild(model1.get());
root->addChild( mt.get() );
osg::MatrixTransform *mt1 = dynamic_cast <osg::MatrixTransform*> (model1.get());
osg::ref_ptr<ModelController> ctrler =new ModelController(mt1);
osgViewer::Viewer viewer;
viewer.addEventHandler( ctrler.get() );
viewer.getCamera()->setViewMatrixAsLookAt(
osg::Vec3(0.0f,-100.0f,0.0f), osg::Vec3(), osg::Z_AXIS );
viewer.setSceneData( root.get() );
viewer.addEventHandler(new osgViewer::WindowSizeHandler);
return viewer.run();
}
您可以使用新的MatrixTransform
来实现这一点。不要将奶牛和粪尿都插入同一个MatrixTransform
中,而是使用两个:
osg::ref_ptr<osg::MatrixTransform> mt = new osg::MatrixTransform;
mt->addChild( model.get() );
osg::ref_ptr<osg::MatrixTransform> mt2 = new osg::MatrixTransform;
mt2->addChild(model1.get());
root->addChild( mt.get() );
root->addChild( mt2.get() );
然后你可以把你想要的MatrixTransform
传给Controller
,让另一个模型"固定":
osg::ref_ptr<ModelController> ctrler =new ModelController(mt2);