12.15
因为以后工作的需要，需要熟悉OGRE引擎。先从熟悉SDK的使用入手吧。
OgreSDK1.7.1提供的Sample，繁杂的内容过多。我列了个简单的代码，暂能够跑一个简单的OGRE程序（新手一定很喜欢^__^）。代码如下：
//-----------------------------------------------------------------------------------------------------------------------
#include "OgrePrerequisites.h"
#include "OgreRoot.h"
#include "OgreWindowEventUtilities.h"
#include "OgreRenderWindow.h"
#include "OgreSceneManager.h"
#include "OgreCamera.h"
#include "OIS/OIS.h"
#include "windows.h"
Ogre::Root* mRoot; // OGRE root
Ogre::RenderWindow* mWindow; // render window
Ogre::SceneManager* mSceneMgr;
Ogre::Camera *mCamera;
OIS::InputManager* mInputMgr; // OIS input manager
INT WINAPI WinMain(HINSTANCE, HINSTANCE, LPSTR, INT)
{
mRoot = 0;
mWindow = 0;
Ogre::String pluginsPath = Ogre::StringUtil::BLANK;
#ifdef _DEBUG
mRoot = OGRE_NEW Ogre::Root("plugins_d.cfg");
#else
mRoot = OGRE_NEW Ogre::Root();
#endif
mRoot->showConfigDialog();
mWindow = mRoot->initialise(true);
mSceneMgr = mRoot->createSceneManager(Ogre::ST_GENERIC, "MySceneManager");
mCamera = mSceneMgr->createCamera("MainCam");
mCamera->setAspectRatio(1.333333f);
mCamera->setFOVy(Ogre::Radian(45.0f));
mCamera->setNearClipDistance(1.0f);
mCamera->setFarClipDistance(1000.0f);
mCamera->setPosition(0, 10, 0);
Ogre::Viewport * vp1 = mWindow->addViewport(mCamera);
Ogre::Viewport * vp2 = mWindow->addViewport(mCamera,1,0.5f,0.0f,0.5f,0.5f);
Ogre::Viewport * vp3 = mWindow->addViewport(mCamera,2,0.0f,0.5f,0.5f,0.5f);
Ogre::Viewport * vp4 = mWindow->addViewport(mCamera,3,0.5f,0.5f,0.5f,0.5f);
vp1->setBackgroundColour(Ogre::ColourValue());
vp2->setBackgroundColour(Ogre::ColourValue(0.0,0.0,1.0));
vp3->setBackgroundColour(Ogre::ColourValue(0.0,1.0,1.0));
vp4->setBackgroundColour(Ogre::ColourValue(1.0,0.0,1.0));
bool run =true;
while ( run )
{
Ogre::WindowEventUtilities::messagePump();
if (!mRoot->_fireFrameStarted())
break;
if ( mWindow->isClosed() )
break;
if (!mRoot->_updateAllRenderTargets())
break;
if (!mRoot->_fireFrameEnded())
break;
//mWindow->update();
}
//mRoot->startRendering(); // start the render loop
mRoot->saveConfig();
mRoot->shutdown();
if (mRoot) OGRE_DELETE mRoot;
return 0;
}
//-----------------------------------------------------------------------------------------------------------------------
运行界面：
另外，抽空理了理OGRE的一些要素，以下是官方提供的一张框架图，做为参考。
Ogre中Root挂了很多Node，Node下可以挂其他的Node。这些Node一般是可绘制的节点，称之为Renderable，Node通常又包含了一些MovableObject，
MovableObject可以是Camera，Light，Entity（包含了位置、选择等信息）等。Node通常又拥有一个AABB（可通过MovableObject及子Node节点的AABB算出），这个AABB供SceneManager进行可见性判断。如果可见的话，Node（Renderable）被放入一个Map组织的渲染队列RenderQueue，RenderQueue会针对Renderable的情况排序。最后再统一批次做Renderable的渲染。
