snow.h

series 60 自带的一个三维程序

/* Copyright (c) 2004, Nokia. All rights reserved */

#ifndef __SNOWH__
#define __SNOWH__

//  INCLUDES

#include <e32base.h> // for CBase definition
#include <GLES\gl.h>      // OpenGL ES header file
#include "utils.h"

// MACROS

#define FRUSTUM_LEFT   -1.f     //left vertical clipping plane
#define FRUSTUM_RIGHT  +1.f     //right vertical clipping plane
#define FRUSTUM_BOTTOM -1.f     //bottom horizontal clipping plane
#define FRUSTUM_TOP    +1.f     //top horizontal clipping plane
#define FRUSTUM_NEAR   +3.f     //near depth clipping plane
#define FRUSTUM_FAR    +1000.f  //far depth clipping plane

// FORWARD DECLARATIONS

class CSnowfall;

/**
*	Snow effect core class
*/

class CSnow 
	: public CFiniteStateMachine, public MTextureLoadingListener
	{
	public: // Constructors and destructor

		static CSnow* NewL( TUint aWidth, TUint aHeight );
		virtual ~CSnow();

	public: // New functions.
		enum 
		{
		ELoadingTextures, 
		ERunning
		};	//application states:
			// ELoadingTextures - indicates that the app. is loading textures
			// ERunning - indicates that the app. is running

		/** 
		* Application initialization
		*/
		void AppInitL( void );
		
		/** 
		* Application exit cleanup
		*/
		void AppExit( void );

		/** 
		* Drawing the ground plane
		*/
		void DrawPlane();
		
		/**
		* Draw a tree
		*/
		void DrawTree( GLfloat aX, GLfloat aZ );
		
		/** 
		* Draw clouds
		*/
		void DrawCloud();
		
		/**
		* Animation step. Draw and animate objects
		*/
		void AppCycle( TInt aFrame );

		/** 
		* State machine handler
		* @param aState State entered
		*/
		void OnEnterStateL( TInt aState );

		// MTextureLoadingListener interface implemetations:
		/**
		* Method called on loading textures
		*/
		void OnStartLoadingTexturesL();
		
		/** 
		* Method called when texture loaded
		*/
		void OnEndLoadingTexturesL();

		/**
		* Texture-manager setup
		* @param aTextureManager Pointer to a texture manager
		*/
		void SetTextureManager( CTextureManager * aTextureManager );

		/**
		* Get pointer to the particle-engine effect
		* @return Effect
		*/
		CSnowfall* GetSnowfall();
    
		/**
		* Ticker-timer get
		* @return The system time
		*/
		TTime GetTimeTick(); 

		/**
		* Total time get
		* @return The elapsed time (in sec.) between the current and the previous frame
		*/
		GLfloat GetElapsedTime();
		
		/**
		* Frames-per-second count.
		* @return Current frames per second
		*/
		GLfloat GetFPSCount();

	protected:
        /**
        * C++ default constructor.
        */
		CSnow( TUint aWidth, TUint aHeight );
        
		/**
        * Symbian 2nd phase constructor.
        */
		void ConstructL( void );
    
	private: // Data
		// Screen width
		TUint iScreenWidth;
		// Screen height
		TUint iScreenHeight;

		// Owns: Texture manager
		CTextureManager* iTextureManager;
    
		// Tree texture
		TTexture iTreeTexture;
		// Ground texture
		TTexture iGroundTexture;
		// Cloud texture
		TTexture iCloudTexture;
		// Cloud texture coordinates
		GLfloat iCloudTextureCoords[8];
		// Texture offset
		GLfloat iTextureOffset;

		// Owns: Pointer to snowfall-effect
		CSnowfall* iSnowfall;

		// Camera
		TCamera iCamera;
		// Reference time
		TTime iT0;
		// Reference time + time delta
		TTime iT1;
		// Elapsed time = iT1 - iT0
		GLfloat iElapsedTime;
		// Current frames per second
		GLfloat iFPSCount;
	};

/**
* Snowfall particle effect class
*/

class CSnowfall: public CParticleEngine
{
	public: // Constructors and destructor
		// Creates and initializes a CSnowfall object.
		static CSnowfall* NewL(GLint aParticlesCount, TVector aPosition,
							   GLfloat aWidth, GLfloat aDepth, GLfloat aGroundLevel,
							   CTextureManager* aTextureManager);
		// Destructor
		virtual ~CSnowfall();
	protected: 
		CSnowfall::CSnowfall();
		void ConstructL(GLint aParticlesCount, TVector aPosition,
						GLfloat aWidth, GLfloat aDepth, GLfloat aGroundLevel,
						CTextureManager * aTextureManager);
    
	public: // Functions from base classes

		// implementation of CParticleEngine::ResetParticle(GLint)
		void ResetParticle(GLint aIndex); 
		// implementation of CParticleEngine::UpdateEngine(GLfloat aElapsedTime)
		void UpdateEngine(GLfloat aElapsedTime);
		// implementation of CParticleEngine::RenderEngine(TCamera &)
		void RenderEngine(TCamera& aCamera);

	public: // Data
		// Width
		GLfloat iWidth;
		// Depth
		GLfloat	iDepth; 
		// Ground level
		GLfloat iGroundLevel;
		/*
		 snowflakes are released from within
		 the rectangle (CParticleEngine::iPosition.iX-iWidth/2, CParticleEngine::iPosition.iY, iPosition.iX-iWidth/2)
					   (CParticleEngine::iPosition.iX+iWidth/2, CParticleEngine::iPosition.iY, iPosition.iX+iWidth/2).
		 Once their height is < iGroundLevel, they are reset.
		*/


	protected: // Data
		// Seed for the random generator.
		TInt64 iSeed; 
		// Snowflake texture
		TTexture iTexture; 
};


#endif

// End of File