osg场景水面倒影问题

lijieguang2124

请教场景水面倒影问题。我的程序是基于osgearth开发的场景，在地形上绘制了一个水面，在水面上反射了天空纹理。但是对于地面上的建筑物倒影是错误的，而且建筑物倒影会随着场景视点的变化而移动，以致消失。如下图：

建筑物倒影问题

我的RTT相机设置如下：

        //相机设置
        setClearColor( osg::Vec4(0.0,0.0,0.0,0.0) );
        setClearMask( GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT );
        setRenderTargetImplementation( osg::Camera::FRAME_BUFFER_OBJECT );
        setReferenceFrame(osg::Transform::ReferenceFrame::ABSOLUTE_RF);
        setRenderOrder( osg::Camera:RE_RENDER );

        //RTT相机输出的纹理
        m_pTexture=new osg::Texture2D;
        m_pTexture->setWrap(osg::Texture2D::WRAP_S,osg::Texture2D::REPEAT);
        m_pTexture->setWrap(osg::Texture2D::WRAP_T,osg::Texture2D::REPEAT);
        m_pTexture->setFilter( osg::Texture::MIN_FILTER, osg::Texture:INEAR );
        m_pTexture->setFilter( osg::Texture::MAG_FILTER, osg::Texture::LINEAR_MIPMAP_LINEAR );

        m_pTexture->setInternalFormat( GL_RGBA );
        m_pTexture->setTextureSize(1024,1024);
        attach( osg::Camera::COLOR_BUFFER,m_pTexture.get() );

下面是RTT相机的回调函数
void RefCameraCallBack:perator() (osg::Node *node, osg::NodeVisitor *nv)
{
        //_cankaoCamera是场景主相机

        _RttCamera=dynamic_cast<osg::Camera *>(node);
        //if(_RttCamera==NULL)
        //osg::ref_ptr<osg::GraphicsContext::WindowingSystemInterface> wsi=osg::GraphicsContext::getWindowingSystemInterface();
        //if(!wsi) return;

        //osg::GraphicsContext::ScreenIdentifier screen(0);
        //wsi->getScreenResolution(screen,width,height);
        const osg::GraphicsContext::Traits * traits=_cankaoCamera->getGraphicsContext()->getTraits();
        w_h=traits->width/traits->height;

        _time=_cankaoCamera->getView()->getFrameStamp()->getSimulationTime();
        //_cankaoCamera->getViewMatrixAsLookAt(_eye_Positon,_eye_Center,_eye_Up);

       
        //_RttCamera->setViewMatrixAsLookAt(_eye_Positon,_eye_Center,_eye_Up);
        double  aspectRatio,zNear, zFar;
        _cankaoCamera->getProjectionMatrixAsPerspective(fovy,aspectRatio,zNear,zFar);

        w_h=float(aspectRatio);
        double newAspect=traits->width/traits->height;
        double yizi=newAspect/aspectRatio;
        //_RttCamera->setProjectionMatrix(_cankaoCamera->getProjectionMatrix()*osg::Matrix::scale(1.0/yizi,1.0,1.0));

        _RttCamera->setViewMatrix(_cankaoCamera->getViewMatrix());

        //_RttCamera->setProjectionMatrixAsPerspective(fovy,1.0/yizi,zNear,zFar);
        _RttCamera->setProjectionMatrix(_cankaoCamera->getProjectionMatrix());
        //_RttCamera->setViewMatrixAsLookAt(_eye_Positon,_eye_Center,_eye_Up);
}

下面是将建筑物添加到RTT相机
void SetupReflectionNode(osg::Node* pRefNode)
{
        osg::MatrixTransform* reverseMatrix = new osg::MatrixTransform;

        osg::Matrix mat = pModemat->getMatrix();
        reverseMatrix->setReferenceFrame(osg::Transform::ReferenceFrame::RELATIVE_RF);
        reverseMatrix->preMult(
                osg::Matrix::scale(1.0f,1.0f,-1.0f)*
                osg::Matrix::translate(0.0f,0.0f,-waterHeight));
        m_pWaterRTTCamera->setClearColor(osg::Vec4(0.0,0.0,0.0,0.0));
        reverseMatrix->addChild(pRefNode);

        m_pWaterRTTCamera->addChild(reverseMatrix);
}

这个问题是不是相机的矩阵设置错误？？

buaahc

肯定是纹理坐标不对 应该将剪裁坐标变到【0-1】之间，直接作为纹理坐标 贴上去