Qt例程代码分析之basicshapes-cpp

由于毕业设计设计机器人仿真，但一直想学习Qt。于是，痛下决心，从MFC平台转移到Qt上来。现在开始学习如何使用Qt 3D做一个机器人仿真环境出来。分析了一下教程的例程，不是很难，但为了以后查阅方便，所以现在这里。

下面是例程的运行结果： 我选择这个例子是因为许多例程中直接是显示模型出来的，但没有提到如何结合按钮来实现一些交互。这个例子就很好，便于学习。

#include "scenemodifier.h" #include <QGuiApplication> #include <Qt3DRender/qcamera.h> #include <Qt3DCore/qentity.h> #include <Qt3DRender/qcameralens.h> //界面需要的头文件 #include <QtWidgets/QApplication> #include <QtWidgets/QWidget> #include <QtWidgets/QHBoxLayout> #include <QtWidgets/QCheckBox> #include <QtWidgets/QCommandLinkButton> #include <QtGui/QScreen> //Qt3D头文件，具体作用后续再讲 #include <Qt3DInput/QInputAspect> #include <Qt3DExtras/qtorusmesh.h> #include <Qt3DRender/qmesh.h> #include <Qt3DRender/qtechnique.h> #include <Qt3DRender/qmaterial.h> #include <Qt3DRender/qeffect.h> #include <Qt3DRender/qtexture.h> #include <Qt3DRender/qrenderpass.h> #include <Qt3DRender/qsceneloader.h> #include <Qt3DRender/qpointlight.h> #include <Qt3DCore/qtransform.h> #include <Qt3DCore/qaspectengine.h> #include <Qt3DRender/qrenderaspect.h> #include <Qt3DExtras/qforwardrenderer.h> #include <Qt3DExtras/qt3dwindow.h> #include <Qt3DExtras/qfirstpersoncameracontroller.h> int main(int argc, char **argv) { //这句雷打不打要写... QApplication app(argc, argv); //首先创建一个场景，用于显示你要绘制或者导入模型，关键语句 Qt3DExtras::Qt3DWindow *view = new Qt3DExtras::Qt3DWindow(); //设置场景背景颜色 view->defaultFrameGraph()->setClearColor(QColor(QRgb(0x4d4d4f))); //如果将3d放置在界面中，则需要创建一个widget来“装”它，container这名字起得生动 QWidget *container = QWidget::createWindowContainer(view); //设置场景大小 QSize screenSize = view->screen()->size(); //当你缩小对话框时，你希望它最小是多少 container->setMinimumSize(QSize(100, 200)); //当你缩小对话框时，你希望它最大是多少 container->setMaximumSize(screenSize); //关键语句，创建对话框 QWidget *widget = new QWidget; //水平布局 QHBoxLayout *hLayout = new QHBoxLayout(widget); //垂直布局 QVBoxLayout *vLayout = new QVBoxLayout(); vLayout->setAlignment(Qt::AlignTop); //将3d场景veiw放到widget中，关键语 hLayout->addWidget(container, 1); hLayout->addLayout(vLayout); widget->setWindowTitle(QStringLiteral("Basic shapes")); //不懂 Qt3DInput::QInputAspect *input = new Qt3DInput::QInputAspect; view->registerAspect(input); //创建根实体，我理解就是创建一个基础实体，然后用它来创建其他的实体 Qt3DCore::QEntity *rootEntity = new Qt3DCore::QEntity(); // 创建相机，设置视角 Qt3DRender::QCamera *cameraEntity = view->camera(); //观测视角 cameraEntity->lens()->setPerspectiveProjection(45.0f, 16.0f/9.0f, 0.1f, 1000.0f); //相机放哪里？ cameraEntity->setPosition(QVector3D(0, 0, 20.0f)); cameraEntity->setUpVector(QVector3D(0, 1, 0)); //视角中心在哪里？ cameraEntity->setViewCenter(QVector3D(0, 0, 0)); //创建各种模型实体 Qt3DCore::QEntity *lightEntity = new Qt3DCore::QEntity(rootEntity); Qt3DRender::QPointLight *light = new Qt3DRender::QPointLight(lightEntity); light->setColor("white"); light->setIntensity(1); lightEntity->addComponent(light); Qt3DCore::QTransform *lightTransform = new Qt3DCore::QTransform(lightEntity); lightTransform->setTranslation(cameraEntity->position()); lightEntity->addComponent(lightTransform); // 设置相机控制，什么第一视场什么的，不是很懂，待补充。 Qt3DExtras::QFirstPersonCameraController *camController = new Qt3DExtras::QFirstPersonCameraController(rootEntity); camController->setCamera(cameraEntity); //场景修改？ SceneModifier *modifier = new SceneModifier(rootEntity); // 关键语句，将这么多实体加载进view当中... view->setRootEntity(rootEntity); //手工码控件 QCommandLinkButton *info = new QCommandLinkButton(); info->setText(QStringLiteral("Qt3D ready-made meshes")); info->setDescription(QString::fromLatin1("Qt3D provides several ready-made meshes, like torus, cylinder, cone, " "cube, plane and sphere.")); info->setIconSize(QSize(0,0)); QCheckBox *torusCB = new QCheckBox(widget); torusCB->setChecked(true); torusCB->setText(QStringLiteral("Torus")); QCheckBox *coneCB = new QCheckBox(widget); coneCB->setChecked(true); coneCB->setText(QStringLiteral("Cone")); QCheckBox *cylinderCB = new QCheckBox(widget); cylinderCB->setChecked(true); cylinderCB->setText(QStringLiteral("Cylinder")); QCheckBox *cuboidCB = new QCheckBox(widget); cuboidCB->setChecked(true); cuboidCB->setText(QStringLiteral("Cuboid")); QCheckBox *planeCB = new QCheckBox(widget); planeCB->setChecked(true); planeCB->setText(QStringLiteral("Plane")); QCheckBox *sphereCB = new QCheckBox(widget); sphereCB->setChecked(true); sphereCB->setText(QStringLiteral("Sphere")); // vLayout->addWidget(info); vLayout->addWidget(torusCB); vLayout->addWidget(coneCB); vLayout->addWidget(cylinderCB); vLayout->addWidget(cuboidCB); vLayout->addWidget(planeCB); vLayout->addWidget(sphereCB); //信号与槽好基友，根据checkBox的状态来选择是否显示模型 QObject::connect(torusCB, &QCheckBox::stateChanged, modifier, &SceneModifier::enableTorus); QObject::connect(coneCB, &QCheckBox::stateChanged, modifier, &SceneModifier::enableCone); QObject::connect(cylinderCB, &QCheckBox::stateChanged, modifier, &SceneModifier::enableCylinder); QObject::connect(cuboidCB, &QCheckBox::stateChanged, modifier, &SceneModifier::enableCuboid); QObject::connect(planeCB, &QCheckBox::stateChanged, modifier, &SceneModifier::enablePlane); QObject::connect(sphereCB, &QCheckBox::stateChanged, modifier, &SceneModifier::enableSphere); //先设置默认情况 torusCB->setChecked(true); coneCB->setChecked(true); cylinderCB->setChecked(true); cuboidCB->setChecked(true); planeCB->setChecked(true); sphereCB->setChecked(true); //显示窗口 widget->show(); //设置大小 widget->resize(1200, 800); //雷打不动第二句 return app.exec(); }

分析得简单粗暴，但会继续研究这个代码，并且不断更新，直到自己对这里的每一句都非常熟悉！