OpenGL模型控制（旋转、平移）

1.效果图

2.平移

首先做一个鼠标双击事件，表示平移模型对象，当然，我们需要遍历当前哪个模型对象被选中，才能进行该对象的平移操作。

void AXBOpemglWidget::mouseDoubleClickEvent(QMouseEvent *event)
{
    Q_UNUSED(event);
    if(m_modelMoving){
        //再次双击取消移动
        m_modelMoving=false;
    }else
        foreach(auto modelInfo,m_Models){
            //双击启动移动
            if(modelInfo.isSelected==true)
                m_modelMoving=true;
            qDebug()<

开启平移后，重写鼠标移动事件，将物体的需要移动到的像素坐标转化为世界坐标。

void AXBOpemglWidget::mouseMoveEvent(QMouseEvent *event)
{
    makeCurrent();
    if(m_modelMoving){
        for(auto iter=m_Models.begin();iter!=m_Models.end();iter++){
            ModelInfo *modelInfo=&iter.value();
            if(!modelInfo->isSelected) continue;
            modelInfo->worldPos=
                    QVector3D(worldPosFromViewPort(event->pos().x(),event->pos().y()));
        }
    }
    doneCurrent();
}

然后再绘制的时候， 使用model.translate(modelInfo.worldPos)即可。

    foreach(auto modelInfo,m_Models){
        model.setToIdentity();
        model.translate(modelInfo.worldPos);

        model.rotate(modelInfo.pitch,QVector3D(1.0,0.0,0.0));
        model.rotate(modelInfo.yaw,QVector3D(0.0,1.0,0.0));
        model.rotate(modelInfo.roll,QVector3D(0.0,0.0,1.0));
        m_ShaderProgram.setUniformValue("model", model);
        modelInfo.model->Draw(m_ShaderProgram);
    }

3.旋转

首先判断当前的模型是否被选中。重写鼠标左键单击事件。

void AXBOpemglWidget::mousePressEvent(QMouseEvent *event)
{
    bool hasSelected=false;
    makeCurrent();
    lastPos=event->pos();
    if(event->buttons()&Qt::LeftButton){

        QVector4D wolrdPostion=worldPosFromViewPort(event->pos().x(),
                                                    event->pos().y());
        mousePickingPos(QVector3D(wolrdPostion));

        for(QMap::iterator iter=m_Models.begin();iter!=m_Models.end();iter++){
            ModelInfo *modelInfo=&iter.value();
            float r=(modelInfo->model->m_maxY-modelInfo->model->m_minY)/2;
            if(modelInfo->worldPos.distanceToPoint(QVector3D(wolrdPostion))isSelected=true;
                hasSelected=true;
            }
            else
                modelInfo->isSelected=false;
            //            qDebug()<worldPos.distanceToPoint(QVector3D(wolrdPostion))
            //             <<"<"<isSelected;
        }
    }

    doneCurrent();
}

重写鼠标移动事件，改变其欧拉角。

void AXBOpemglWidget::mouseMoveEvent(QMouseEvent *event)
{
    makeCurrent();
    if(m_modelMoving){
        for(auto iter=m_Models.begin();iter!=m_Models.end();iter++){
            ModelInfo *modelInfo=&iter.value();
            if(!modelInfo->isSelected) continue;
            modelInfo->worldPos=
                    QVector3D(worldPosFromViewPort(event->pos().x(),event->pos().y()));
        }
    }else
        if(event->buttons() & Qt::RightButton
                || event->buttons() & Qt::LeftButton
                || event->buttons() & Qt::MiddleButton){

            auto currentPos=event->pos();
            QPoint deltaPos=currentPos-lastPos;
            lastPos=currentPos;
            if(event->buttons() & Qt::RightButton)
                m_camera.ProcessMouseMovement(deltaPos.x(),-deltaPos.y());
            else
                for(auto iter=m_Models.begin();iter!=m_Models.end();iter++){
                    ModelInfo *modelInfo=&iter.value();
                    if(!modelInfo->isSelected) continue;
                    if(event->buttons() & Qt::MiddleButton){
                        modelInfo->roll+=deltaPos.x();
                    }
                    else if(event->buttons() & Qt::LeftButton){
                        modelInfo->yaw+=deltaPos.x();
                        modelInfo->pitch+=deltaPos.y();
                    }
                }

        }
    doneCurrent();
}

4.完整工程

https://download.csdn.net/download/wzz953200463/87941666https://download.csdn.net/download/wzz953200463/87941666

5.相关参考

OpenGL 齐次坐标_Mr.codeee的博客-CSDN博客

OpenGL 坐标系统_Mr.codeee的博客-CSDN博客

OpenGL模型加载_Mr.codeee的博客-CSDN博客

OpenGL 鼠标拾取模型_Mr.codeee的博客-CSDN博客