OGER SDK研究之七 Transparency 透明

/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2006 Torus Knot Software Ltd
Also see acknowledgements in Readme.html

You may use this sample code for anything you like, it is not covered by the
LGPL like the rest of the engine.
-----------------------------------------------------------------------------
*/

/**
    /file
        Transparency.h  透明度
    /brief
        Specialisation of OGRE's framework application to show the transparency,
        or scene blending features.
    /par
        Note that this is a little rudimentary - it's because whilst
        OGRE supports lots of blending options, the SceneManager has
        to ensure the rendering order is correct when object transparency
        is enabled. Right now this is not quite right in the default
        manager so this scene is kept deliberately simple.
*/

#include "ExampleApplication.h"

class TransApplication : public ExampleApplication
{
public:
    TransApplication() {}

protected:

    // Just override the mandatory create scene method
    void createScene(void)
    {
        // Set ambient light
  //创建一个环境光
        mSceneMgr->setAmbientLight(ColourValue(0.5, 0.5, 0.5));

        // Create a light
  //创建一个灯光
        Light* l = mSceneMgr->createLight("MainLight");
        // Accept default settings: point light, white diffuse, just set position
        // NB I could attach the light to a SceneNode if I wanted it to move automatically with
        //  other objects, but I don't
  //设置灯光的位置
        l->setPosition(20,80,50);

        // Create a prefab plane
  //创建一个缺省的平面实体
        Entity *planeEnt = mSceneMgr->createEntity("Plane", SceneManager::PT_PLANE);
        // Give the plane a texture
  //设置平面的材质
        planeEnt->setMaterialName("Examples/BumpyMetal");

        // Create an entity from a model (will be loaded automatically)
  //由模型文件创建一个实体
        Entity* knotEnt = mSceneMgr->createEntity("Knot", "knot.mesh");
  //设置模型的材质(这是关键，用材质达到透明的效果）
        knotEnt->setMaterialName("Examples/TransparentTest");

        // Attach the 2 new entities to the root of the scene
  //取得场景指针
        SceneNode* rootNode = mSceneMgr->getRootSceneNode();

  //将两个实体加入场景
        rootNode->attachObject(planeEnt);
        rootNode->attachObject(knotEnt);

        // Add a whole bunch of extra transparent entities
  //克隆10个模型并加入场景
        Entity *cloneEnt;
        for (int n = 0; n < 10; ++n)
        {
            // Create a new node under the root
            SceneNode* node = mSceneMgr->createSceneNode();
            // Random translate
            Vector3 nodePos;
            nodePos.x = Math::SymmetricRandom() * 500.0;
            nodePos.y = Math::SymmetricRandom() * 500.0;
            nodePos.z = Math::SymmetricRandom() * 500.0;
            node->setPosition(nodePos);
            rootNode->addChild(node);
            // Clone knot
            char cloneName[12];
            sprintf(cloneName, "Knot%d", n);
            cloneEnt = knotEnt->clone(cloneName);
            // Attach to new node
            node->attachObject(cloneEnt);

        }
    }

};
/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2006 Torus Knot Software Ltd
Also see acknowledgements in Readme.html

You may use this sample code for anything you like, it is not covered by the
LGPL like the rest of the engine.
-----------------------------------------------------------------------------
*/
/**
    /file
        Transparency.cpp
    /brief
        Shows OGRE's transparency, or scene blending features.
    /par
        Note that this is a little rudimentary - it's because whilst
        OGRE supports lots of blending options, the SceneManager has
        to ensure the rendering order is correct when object transparency
        is enabled. Right now this is not quite right in the default
        manager so this scene is kept deliberately simple.
*/

#include "Transparency.h"

#if OGRE_PLATFORM == OGRE_PLATFORM_WIN32
#define WIN32_LEAN_AND_MEAN
#include "windows.h"
#endif

#ifdef __cplusplus
extern "C" {
#endif

#if OGRE_PLATFORM == OGRE_PLATFORM_WIN32
INT WINAPI WinMain( HINSTANCE hInst, HINSTANCE, LPSTR strCmdLine, INT )
#else
int main(int argc, char ** argv)
#endif
{

    // Create application object
    TransApplication app;

    try {
        app.go();
    } catch( Ogre::Exception& e ) {
#if OGRE_PLATFORM == OGRE_PLATFORM_WIN32
        MessageBox( NULL, e.getFullDescription().c_str(), "An exception has occured!", MB_OK | MB_ICONERROR | MB_TASKMODAL);
#else
        std::cerr << "An exception has occured: " << e.getFullDescription();
#endif
    }

    return 0;
}

#ifdef __cplusplus
}
#endif

 

对应的材质脚本

material Examples/TransparentTest
{
 technique
 {
  pass
  {
   ambient 0.2 0.2 0.2         //顶点环境光
   scene_blend add              //两张纹理的混合方式为相加
   depth_write off               //关闭深度写入,即没有Z缓冲效果

   texture_unit
   {
    texture Water01.jpg         //纹理
    scroll_anim 0.25 0           //纹理动画方式为x轴方向速度0.25
   }

   texture_unit
   {
    texture Water01.jpg         //纹理
    wave_xform scroll_y sine 0 0.1 0 0.5         //纹理动画方式为水波形,及y轴运动.
   }
  }
 }
}