Ogre笔记七：基础教程四—帧监听器和非缓冲输入

非缓冲输入，个人觉得不怎么好用，但是在某些特殊场景下可能会有大用。

首先，我们了解一下这一节教程想实现个什么东西：

我们将把一个忍者放到屏幕中，并在场景中加上点光源。

当你点击鼠标左键，灯光会打开或关闭。按住鼠标右键，则开启“鼠标观察”模式（也就是你用摄像机四处观望，想想一下你玩3D游戏的场景）。

按下1、2键，以选择从哪一个视口来观看场景。

#include "ExampleApplication.h"class TutorialFrameListener : public ExampleFrameListener{public:TutorialFrameListener(RenderWindow* win, Camera* cam, SceneManager *sceneMgr): ExampleFrameListener(win, cam, false, false){// 键盘和鼠标状态追踪mMouseDown = false;mToggle = 0.0;// Populate the camera and scene manager containersmCamNode = cam->getParentSceneNode();mSceneMgr = sceneMgr;// 设置旋转和移动速度mRotate = 0.13;mMove = 250;}bool frameStarted(const FrameEvent &evt){mMouse->capture();mKeyboard->capture();//Escape键被按下时程序退出if(mKeyboard->isKeyDown(OIS::KC_ESCAPE))return false;//左击鼠标控制灯的开关bool currMouse = mMouse->getMouseState().buttonDown(OIS::MB_Left);if (currMouse && ! mMouseDown){Light *light = mSceneMgr->getLight("Light1");light->setVisible(! light->isVisible());}mMouseDown = currMouse;//事件之间的休息时间mToggle -= evt.timeSinceLastFrame;//按1、2键，能够转换摄像机的视口if ((mToggle < 0.0f ) && mKeyboard->isKeyDown(OIS::KC_1)){mToggle = 0.5f;mCamera->getParentSceneNode()->detachObject(mCamera);mCamNode = mSceneMgr->getSceneNode("CamNode1");mCamNode->attachObject(mCamera);}else if ((mToggle < 0.0f) && mKeyboard->isKeyDown(OIS::KC_2)){mToggle = 0.5f;mCamera->getParentSceneNode()->detachObject(mCamera);mCamNode = mSceneMgr->getSceneNode("CamNode2");mCamNode->attachObject(mCamera);}//按下方向键或W、A、S、D键时，进行mCamNode的平移Vector3 transVector = Vector3::ZERO;if (mKeyboard->isKeyDown(OIS::KC_UP) || mKeyboard->isKeyDown(OIS::KC_W))transVector.z -= mMove;if (mKeyboard->isKeyDown(OIS::KC_DOWN) || mKeyboard->isKeyDown(OIS::KC_S))transVector.z += mMove;if (mKeyboard->isKeyDown(OIS::KC_LEFT) || mKeyboard->isKeyDown(OIS::KC_A))transVector.x -= mMove;if (mKeyboard->isKeyDown(OIS::KC_RIGHT) || mKeyboard->isKeyDown(OIS::KC_D))transVector.x += mMove;//E键或者PageDown键进行向下移动，用Q键或者PageUp键进行向上移动if (mKeyboard->isKeyDown(OIS::KC_PGUP) || mKeyboard->isKeyDown(OIS::KC_Q))transVector.y += mMove;if (mKeyboard->isKeyDown(OIS::KC_PGDOWN) || mKeyboard->isKeyDown(OIS::KC_E))transVector.y -= mMove;//摄像机旋转mCamNode->translate(transVector*evt.timeSinceLastFrame,Node::TS_LOCAL);if (mMouse->getMouseState().buttonDown(OIS::MB_Right)){mCamNode->yaw(Degree(-mRotate * mMouse->getMouseState().X.rel), Node::TS_WORLD);mCamNode->pitch(Degree(-mRotate * mMouse->getMouseState().Y.rel), Node::TS_LOCAL);}return true;//return ExampleFrameListener::frameStarted(evt);}protected:bool mMouseDown; // 鼠标左键是否在上一帧被按下Real mToggle; // 直到下一次触发的时间Real mRotate; // 滚动常量Real mMove; // 移动常量SceneManager *mSceneMgr; // 当前场景管理器SceneNode *mCamNode; // 当前摄像机所附在的场景节点};class TutorialApplication : public ExampleApplication{public:TutorialApplication(){}~TutorialApplication(){}protected:void createCamera(void){// create camera, but leave at default positionmCamera = mSceneMgr->createCamera("PlayerCam");mCamera->setNearClipDistance(5);}void createScene(void){//创建一个相对较暗的环境mSceneMgr->setAmbientLight(ColourValue(0.25, 0.25, 0.25));//添加一个忍者Entity *ent = mSceneMgr->createEntity("Ninja", "ninja.mesh");SceneNode *node = mSceneMgr->getRootSceneNode()->createChildSceneNode("NinjaNode");node->attachObject(ent);//添加一个光源Light *light = mSceneMgr->createLight("Light1");light->setType(Light::LT_POINT);light->setPosition(Vector3(250, 150, 250));light->setDiffuseColour(ColourValue::White);light->setSpecularColour(ColourValue::White);// Create the scene nodenode = mSceneMgr->getRootSceneNode()->createChildSceneNode("CamNode1", Vector3(-400, 200, 400));node->yaw(Degree(-45));node->attachObject(mCamera);// create the second camera nodenode = mSceneMgr->getRootSceneNode()->createChildSceneNode("CamNode2", Vector3(0, 200, 400));}void createFrameListener(void){// Create the FrameListenermFrameListener = new TutorialFrameListener(mWindow, mCamera, mSceneMgr);mRoot->addFrameListener(mFrameListener);// Show the frame stats overlaymFrameListener->showDebugOverlay(true);}};#if OGRE_PLATFORM == PLATFORM_WIN32 || OGRE_PLATFORM == OGRE_PLATFORM_WIN32#define WIN32_LEAN_AND_MEAN#include "windows.h"INT WINAPI WinMain(HINSTANCE hInst, HINSTANCE, LPSTR strCmdLine, INT)#elseint main(int argc, char **argv)#endif{// Create application objectTutorialApplication app;try {app.go();} catch(Exception& e) {#if OGRE_PLATFORM == PLATFORM_WIN32 || OGRE_PLATFORM == OGRE_PLATFORM_WIN32MessageBox(NULL, e.getFullDescription().c_str(), "An exception has occurred!", MB_OK |MB_ICONERROR | MB_TASKMODAL);#elsefprintf(stderr, "An exception has occurred: %s\n",e.getFullDescription().c_str());#endif}return 0;}