C++ CPVRTModelPOD::GetCamera方法代码示例

/*!****************************************************************************
 @Function		SetupView()
 @Return		N/A
 @Description	Sets up the view matrices required for the training course
******************************************************************************/
void OGLES3EdgeDetection::SetupView(bool bRotate)
{
	PVRTVec3 vEyePos, vLookAt, vCamUp=PVRTVec3(0.00f, 1.0001f, 0.00f);

	// Checks if a camera is in the scene, if there is, uses it, otherwise creates one.
	if(m_Scene.nNumCamera>0)
	{
		// vLookAt is taken from the target node, or..
		if(m_Scene.pCamera[0].nIdxTarget != -1) m_Scene.GetCameraPos(vEyePos, vLookAt, 0);
		// ..it is calculated from the rotation
		else m_Scene.GetCamera(vEyePos, vLookAt, vCamUp, 0);
	}
	else
	{
		//Creates a camera if none exist.
		vEyePos = PVRTVec3(0, 0, 200);
		vLookAt = PVRTVec3(0, 0, 0);
	}

	// Set the view and projection matrix for rendering to texture.
	m_mR2TView = PVRTMat4::LookAtRH(vEyePos, vLookAt, vCamUp);
	m_mR2TProjection = PVRTMat4::PerspectiveFovRH(PVRT_PI*0.125, (float)m_i32TexWidth/(float)m_i32TexHeight, g_fCameraNear, g_fCameraFar, PVRTMat4::OGL, bRotate);

	// The textured quad this program renders to will be rendered full screen, in orthographic mode, so doesn't need camera variables to be set.
}

/*!****************************************************************************
 @Function		RenderScene
 @Return		bool		true if no error occured
 @Description	Main rendering loop function of the program. The shell will
				call this function every frame.
				eglSwapBuffers() will be performed by PVRShell automatically.
				PVRShell will also manage important OS events.
				Will also manage relevent OS events. The user has access to
				these events through an abstraction layer provided by PVRShell.
******************************************************************************/
bool OGLES3TextureStreaming::RenderScene()
{
	// Clears the color and depth buffer
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

	// Time based animation and locks the app to 60 FPS.
	// Uses the shell function PVRShellGetTime() to get the time in milliseconds.
	unsigned long ulTime = PVRShellGetTime();
	unsigned long ulDeltaTime = ulTime - m_ulTimePrev;
	m_ulTimePrev = ulTime;
	m_fFrame      += (float)ulDeltaTime * (60.0f/1000.0f);
	m_fBandScroll += (float)ulDeltaTime * (60.0f/1000.0f) * c_fBandScrollSpeed;
	if(m_fFrame > m_Scene.nNumFrame - 1)
		m_fFrame = 0.0f;

	if(m_fBandScroll > 1.0f)
		m_fBandScroll = -c_fBandWidth;

	bool bRotate = PVRShellGet(prefIsRotated) && PVRShellGet(prefFullScreen);

	m_Scene.SetFrame(m_fFrame);

	// Setup the main camera
	PVRTVec3	vFrom, vTo(0.0f), vUp(0.0f, 1.0f, 0.0f);
	float fFOV;

	// Camera nodes are after the mesh and light nodes in the array
	int i32CamID = m_Scene.pNode[m_Scene.nNumMeshNode + m_Scene.nNumLight + c_ui32Camera].nIdx;

	// Get the camera position, target and field of view (fov)
	if(m_Scene.pCamera[i32CamID].nIdxTarget != -1) // Does the camera have a target?
		fFOV = m_Scene.GetCameraPos( vFrom, vTo, c_ui32Camera); // vTo is taken from the target node
	else
		fFOV = m_Scene.GetCamera( vFrom, vTo, vUp, c_ui32Camera); // vTo is calculated from the rotation

    float fTargetAspect = 960.0f/640.0f;
    float fAspect       = (float)PVRShellGet(prefWidth) / (float)PVRShellGet(prefHeight);
    fFOV               *= fTargetAspect / fAspect;

	PVRTMat4 mView           = PVRTMat4::LookAtRH(vFrom, vTo, vUp);
	PVRTMat4 mProjection     = PVRTMat4::PerspectiveFovRH(fFOV, (float)PVRShellGet(prefWidth)/(float)PVRShellGet(prefHeight), c_fCameraNear,
														  c_fCameraFar, PVRTMat4::OGL, bRotate);
	PVRTMat4 mViewProjection = mProjection * mView;

	DrawPODScene(mViewProjection);

	// Displays the demo name using the tools. For a detailed explanation, see the training course IntroducingPVRTools
	m_Print3D.DisplayDefaultTitle("Texture Streaming", c_pszDescription, ePVRTPrint3DSDKLogo);
	m_Print3D.Flush();

	++m_i32Frame;
	return true;
}

/*******************************************************************************
 * Function Name  : CameraGetMatrix
 * Global Used    :
 * Description    : Function to setup camera position
 *
 *******************************************************************************/
void OGLESSkinning::CameraGetMatrix()
{
	PVRTVec3	vFrom, vTo, vUp(0.0f, 1.0f, 0.0f);
	float	fFOV;
	bool bRotate = PVRShellGet(prefIsRotated) && PVRShellGet(prefFullScreen);

	//.. get the Camera's position, direction and FOV.
	fFOV = m_Scene.GetCamera(vFrom, vTo, vUp, 0);

	// Set up the view matrix
	m_mView = PVRTMat4::LookAtRH(vFrom, vTo, vUp);

	// Set up the projection matrix
	m_mProjection = PVRTMat4::PerspectiveFovRH(fFOV, (float) PVRShellGet(prefWidth) / (float) PVRShellGet(prefHeight), g_fCameraNear, g_fCameraFar, PVRTMat4::OGL, bRotate);
}

/*!****************************************************************************
 @Function		Update
 @Description	Handles user input and updates all timing data.
******************************************************************************/
void OGLES3ShadowMapping::Update()
{
	if (PVRShellIsKeyPressed(PVRShellKeyNameSELECT)) m_bDebug = !m_bDebug;
	if (PVRShellIsKeyPressed(PVRShellKeyNameLEFT)) m_fBias *= 0.9f;
	if (PVRShellIsKeyPressed(PVRShellKeyNameRIGHT)) m_fBias *= 1.1f;

	// Calculates the frame number to animate in a time-based manner.
	// Uses the shell function PVRShellGetTime() to get the time in milliseconds.
	static unsigned long ulTimePrev = PVRShellGetTime();
	unsigned long ulTime = PVRShellGetTime();
	unsigned long ulDeltaTime = ulTime - ulTimePrev;
	ulTimePrev = ulTime;
	static float fFrame = 0;
	if (!m_bDebug)
		fFrame += (float)ulDeltaTime * 0.05f;

	if (fFrame > m_Scene.nNumFrame-1)
		fFrame = 0;

	// Update the animation data
	m_Scene.SetFrame(fFrame);

	PVRTVec3 vFrom, vTo, vUp;	
	float fFOV = m_Scene.GetCamera(vFrom, vTo, vUp, 0) * 0.75f;
		

	m_mProjection = PVRTMat4::PerspectiveFovRH(fFOV, (float)PVRShellGet(prefWidth)/(float)PVRShellGet(prefHeight), m_Scene.pCamera[0].fNear, m_Scene.pCamera[0].fFar, PVRTMat4::OGL, m_bRotate);
	m_mView = PVRTMat4::LookAtRH(vFrom, vTo, vUp);
	
	m_Scene.GetLight(m_vLightPosition, m_vLightDirection, 0);
	
	PVRTVec3 lightFrom, lightTo, lightUp;
	m_Scene.GetCamera(lightFrom, lightTo, lightUp, 1);
	m_mLightView = PVRTMat4::LookAtRH(lightFrom, lightTo, lightUp);
	m_mLightProjection = PVRTMat4::PerspectiveFovRH(PVRT_PI_OVER_TWO, 1.0f, m_Scene.pCamera[1].fNear, m_Scene.pCamera[1].fFar, PVRTMat4::OGL, m_bRotate);	
}

//.........这里部分代码省略.........
	if(!LoadShaders(&ErrorStr))
	{
		PVRShellSet(prefExitMessage, ErrorStr.c_str());
		return false;
	}

	//	Initialize Print3D
	bool bRotate = PVRShellGet(prefIsRotated) && PVRShellGet(prefFullScreen);

	if(m_Print3D.SetTextures(0,PVRShellGet(prefWidth),PVRShellGet(prefHeight), bRotate) != PVR_SUCCESS)
	{
		PVRShellSet(prefExitMessage, "ERROR: Cannot initialise Print3D\n");
		return false;
	}

	//Set OpenGL ES render states needed for this demo

	// Enable backface culling and depth test
	glCullFace(GL_BACK);
	glEnable(GL_CULL_FACE);

	glEnable(GL_DEPTH_TEST);

	glClearColor(0.0f, 0.0f, 0.0f, 1.0f);

	// Find the largest square power of two texture that fits into the viewport
	m_i32TexSize = 1;
	int iSize = PVRT_MIN(PVRShellGet(prefWidth), PVRShellGet(prefHeight));
	while (m_i32TexSize * 2 < iSize) m_i32TexSize *= 2;

	// Get the currently bound frame buffer object. On most platforms this just gives 0.
	glGetIntegerv(GL_FRAMEBUFFER_BINDING, &m_i32OriginalFB);

	for(int i = 0; i < 2; ++i)
	{
		// Create texture for the FBO
		glGenTextures(1, &m_uiTexture[i]);
		glBindTexture(GL_TEXTURE_2D, m_uiTexture[i]);
		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, m_i32TexSize, m_i32TexSize, 0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, 0);

		glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
		glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
		glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
		glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

		// Create FBO
		glGenFramebuffers(1, &m_uiFbo[i]);
		glBindFramebuffer(GL_FRAMEBUFFER, m_uiFbo[i]);
		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, m_uiTexture[i], 0);

		glGenRenderbuffers(1, &m_uiDepthBuffer[i]);
		glBindRenderbuffer(GL_RENDERBUFFER, m_uiDepthBuffer[i]);

		glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT16, m_i32TexSize, m_i32TexSize);
		glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, m_uiDepthBuffer[i]);

        // Check that our FBO creation was successful
        GLuint uStatus = glCheckFramebufferStatus(GL_FRAMEBUFFER);

        if(uStatus != GL_FRAMEBUFFER_COMPLETE)
        {
            m_bFBOsCreated = false;
            PVRShellOutputDebug("ERROR: Failed to initialise FBO");
            break;
        }

		// Clear the colour buffer for this FBO
		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	}

	glBindFramebuffer(GL_FRAMEBUFFER, m_i32OriginalFB);

	// Setup the main camera
	PVRTVec3	vFrom, vTo(0.0f), vUp(0.0f, 1.0f, 0.0f);
	float fFOV;

	// Camera nodes are after the mesh and light nodes in the array
	int i32CamID = m_Scene.pNode[m_Scene.nNumMeshNode + m_Scene.nNumLight + g_ui32Camera].nIdx;

	// Get the camera position, target and field of view (fov)
	if(m_Scene.pCamera[i32CamID].nIdxTarget != -1) // Does the camera have a target?
		fFOV = m_Scene.GetCameraPos( vFrom, vTo, g_ui32Camera); // vTo is taken from the target node
	else
		fFOV = m_Scene.GetCamera( vFrom, vTo, vUp, g_ui32Camera); // vTo is calculated from the rotation

	m_View = PVRTMat4::LookAtRH(vFrom, vTo, vUp);

	// Calculate the projection matrix
	PVRTMat4 mProjection = PVRTMat4::PerspectiveFovRH(fFOV, (float)PVRShellGet(prefWidth)/(float)PVRShellGet(prefHeight), g_fCameraNear, g_fCameraFar, PVRTMat4::OGL, bRotate);
	m_ViewProjection = mProjection * m_View;

	// Check to see if the GL_EXT_discard_framebuffer extension is supported
    if(m_bFBOsCreated && (m_bDiscard = CPVRTgles2Ext::IsGLExtensionSupported("GL_EXT_discard_framebuffer")) != false)
	{
		m_Extensions.LoadExtensions();
		m_bDiscard = m_Extensions.glDiscardFramebufferEXT != 0;
	}

	return true;
}

/*!****************************************************************************
 @Function		RenderScene
 @Return		bool		true if no error occured
 @Description	Main rendering loop function of the program. The shell will
				call this function every frame.
				eglSwapBuffers() will be performed by PVRShell automatically.
				PVRShell will also manage important OS events.
				Will also manage relevent OS events. The user has access to
				these events through an abstraction layer provided by PVRShell.
******************************************************************************/
bool OGLES2ChameleonMan::RenderScene()
{
	// Clear the color and depth buffer
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

	// Use shader program
	glUseProgram(m_SkinnedShaderProgram.uiId);

	if(PVRShellIsKeyPressed(PVRShellKeyNameACTION1))
	{
		m_bEnableDOT3 = !m_bEnableDOT3;
		glUniform1i(m_SkinnedShaderProgram.auiLoc[ebUseDot3], m_bEnableDOT3);
	}

	/*
		Calculates the frame number to animate in a time-based manner.
		Uses the shell function PVRShellGetTime() to get the time in milliseconds.
	*/
	unsigned long iTime = PVRShellGetTime();

	if(iTime > m_iTimePrev)
	{
		float fDelta = (float) (iTime - m_iTimePrev);
		m_fFrame += fDelta * g_fDemoFrameRate;

		// Increment the counters to make sure our animation works
		m_fLightPos	+= fDelta * 0.0034f;
		m_fWallPos	+= fDelta * 0.00027f;
		m_fBackgroundPos += fDelta * -0.000027f;

		// Wrap the Animation back to the Start
		if(m_fLightPos >= PVRT_TWO_PI)
			m_fLightPos -= PVRT_TWO_PI;

		if(m_fWallPos >= PVRT_TWO_PI)
			m_fWallPos -= PVRT_TWO_PI;

		if(m_fBackgroundPos <= 0)
			m_fBackgroundPos += 1.0f;

		if(m_fFrame > m_Scene.nNumFrame - 1)
			m_fFrame = 0;
	}

	m_iTimePrev	= iTime;

	// Set the scene animation to the current frame
	m_Scene.SetFrame(m_fFrame);

	// Set up camera
	PVRTVec3	vFrom, vTo, vUp(0.0f, 1.0f, 0.0f);
	PVRTMat4 mView, mProjection;
	PVRTVec3	LightPos;
	float fFOV;
	int i;

	bool bRotate = PVRShellGet(prefIsRotated) && PVRShellGet(prefFullScreen);

	// Get the camera position, target and field of view (fov)
	if(m_Scene.pCamera[0].nIdxTarget != -1) // Does the camera have a target?
		fFOV = m_Scene.GetCameraPos( vFrom, vTo, 0); // vTo is taken from the target node
	else
		fFOV = m_Scene.GetCamera( vFrom, vTo, vUp, 0); // vTo is calculated from the rotation

	fFOV *= bRotate ? (float)PVRShellGet(prefWidth)/(float)PVRShellGet(prefHeight) : (float)PVRShellGet(prefHeight)/(float)PVRShellGet(prefWidth);

	/*
		We can build the model view matrix from the camera position, target and an up vector.
		For this we use PVRTMat4::LookAtRH().
	*/
	mView = PVRTMat4::LookAtRH(vFrom, vTo, vUp);

	// Calculate the projection matrix
	mProjection = PVRTMat4::PerspectiveFovRH(fFOV,  (float)PVRShellGet(prefWidth)/(float)PVRShellGet(prefHeight), g_fCameraNear, g_fCameraFar, PVRTMat4::OGL, bRotate);

	// Update Light Position and related VGP Program constant
	LightPos.x = 200.0f;
	LightPos.y = 350.0f;
	LightPos.z = 200.0f * PVRTABS(sin((PVRT_PI / 4.0f) + m_fLightPos));

	glUniform3fv(m_SkinnedShaderProgram.auiLoc[eLightPos], 1, LightPos.ptr());

	// Set up the View * Projection Matrix
	PVRTMat4 mViewProjection;

	mViewProjection = mProjection * mView;
	glUniformMatrix4fv(m_SkinnedShaderProgram.auiLoc[eViewProj], 1, GL_FALSE, mViewProjection.ptr());

	// Enable the vertex attribute arrays
	for(i = 0; i < eNumAttribs; ++i) glEnableVertexAttribArray(i);
//.........这里部分代码省略.........

/*!****************************************************************************
 @Function		RenderScene
 @Return		bool		true if no error occurred
 @Description	Main rendering loop function of the program. The shell will
				call this function every frame.
				eglSwapBuffers() will be performed by PVRShell automatically.
				PVRShell will also manage important OS events.
				Will also manage relevant OS events. The user has access to
				these events through an abstraction layer provided by PVRShell.
******************************************************************************/
bool OGLES3PhantomMask::RenderScene()
{
    if(PVRShellIsKeyPressed(PVRShellKeyNameACTION1))
        m_bEnableSH = !m_bEnableSH;

    // Clear the colour and depth buffer
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    // Draw the background
    m_Background.Draw(m_ui32TexBackground);

    // Enable culling
    glEnable(GL_CULL_FACE);

    // Enable depth testing
    glEnable(GL_DEPTH_TEST);

    // Use shader program
    GLuint ProgramID, MVPLoc, ModelLoc;

    if(m_bEnableSH)
    {
        ProgramID = m_SHShaderProgram.uiId;
        MVPLoc	  = m_SHShaderProgram.auiLoc[eSHMVPMatrix];
        ModelLoc  = m_SHShaderProgram.auiLoc[eSHModel];
    }
    else
    {
        ProgramID = m_DiffuseShaderProgram.uiId;
        MVPLoc	  = m_DiffuseShaderProgram.auiLoc[eDifMVPMatrix];
        ModelLoc  = m_DiffuseShaderProgram.auiLoc[eDifModel];
    }

    glUseProgram(ProgramID);

    /*
    	Calculates the frame number to animate in a time-based manner.
    	Uses the shell function PVRShellGetTime() to get the time in milliseconds.
    */
    unsigned long ulTime = PVRShellGetTime();

    if(ulTime > m_ulTimePrev)
    {
        unsigned long ulDeltaTime = ulTime - m_ulTimePrev;
        m_fFrame += (float)ulDeltaTime * g_fDemoFrameRate;

        if(m_fFrame > m_Scene.nNumFrame - 1)
            m_fFrame = 0;

        // Sets the scene animation to this frame
        m_Scene.SetFrame(m_fFrame);
    }

    m_ulTimePrev = ulTime;

    /*
    	Set up the view and projection matrices from the camera
    */
    PVRTMat4 mView, mProjection;
    PVRTVec3	vFrom, vTo(0.0f), vUp(0.0f, 1.0f, 0.0f);
    float fFOV;

    // Setup the camera
    bool bRotate = PVRShellGet(prefIsRotated) && PVRShellGet(prefFullScreen);

    // Camera nodes are after the mesh and light nodes in the array
    int i32CamID = m_Scene.pNode[m_Scene.nNumMeshNode + m_Scene.nNumLight + g_ui32Camera].nIdx;

    // Get the camera position, target and field of view (fov)
    if(m_Scene.pCamera[i32CamID].nIdxTarget != -1) // Does the camera have a target?
        fFOV = m_Scene.GetCameraPos( vFrom, vTo, g_ui32Camera); // vTo is taken from the target node
    else
        fFOV = m_Scene.GetCamera( vFrom, vTo, vUp, g_ui32Camera); // vTo is calculated from the rotation

    fFOV *= bRotate ? (float)PVRShellGet(prefWidth)/(float)PVRShellGet(prefHeight) : (float)PVRShellGet(prefHeight)/(float)PVRShellGet(prefWidth);

    // We can build the model view matrix from the camera position, target and an up vector.
    // For this we usePVRTMat4LookAtRH()
    mView = PVRTMat4::LookAtRH(vFrom, vTo, vUp);

    // Calculate the projection matrix
    mProjection = PVRTMat4::PerspectiveFovRH(fFOV, (float)PVRShellGet(prefWidth)/(float)PVRShellGet(prefHeight), g_fCameraNear, g_fCameraFar, PVRTMat4::OGL, bRotate);

    SPODNode& Node = m_Scene.pNode[0];

    // Get the node model matrix
    PVRTMat4 mWorld;
    mWorld = m_Scene.GetWorldMatrix(Node);

    // Set the model inverse transpose matrix
//.........这里部分代码省略.........

/*!****************************************************************************
 @Function		InitView
 @Return		bool		true if no error occurred
 @Description	Code in InitView() will be called by PVRShell upon
				initialization or after a change in the rendering context.
				Used to initialize variables that are dependant on the rendering
				context (e.g. textures, vertex buffers, etc.)
******************************************************************************/
bool OGLES3MagicLantern::InitView()
{
	CPVRTString ErrorStr;

	// At this point m_Scene should have been already processed by InitApplication()
	// and all the POD data properly loaded, but lets do a little test just in case.
	 if (!m_Scene.IsLoaded())
	{
		PVRShellSet(prefExitMessage, "ERROR: POD file has not been loaded correctly. Cannot continue. \n");
		return false;
	}

	// Initialize VBO data
	if(!LoadVbos())
	{
		PVRShellSet(prefExitMessage, ErrorStr.c_str());
		return false;
	}

	//	Load and compile the shaders, link programs and load textures.
	if(!LoadPFX())
	{
		return false;
	}

	// Initialize Print3D
	bool bRotate = PVRShellGet(prefIsRotated) && PVRShellGet(prefFullScreen);

	if(m_Print3D.SetTextures(0,PVRShellGet(prefWidth),PVRShellGet(prefHeight), bRotate) != PVR_SUCCESS)
	{
		PVRShellSet(prefExitMessage, "ERROR: Cannot initialise Print3D\n");
		return false;
	}

	// Enable backface culling and depth test
	glCullFace(GL_BACK);
	glEnable(GL_CULL_FACE);
	glEnable(GL_DEPTH_TEST);

	// Black as clear colour
	glClearColor(0.0f, 0.0f, 0.0f, 1.0f);

	// Disable blending
	glDisable(GL_BLEND);
	
	// Set up the view and projection matrices from the camera.
	// The camera does not moves so these matrices only need to be 
	// calculated once.
	// If you want to make the camera dynamic, re-calculate the view matrix 
	// every frame.
	PVRTVec3 vFrom, vTo(0.0f), vUp(0.0f, 1.0f, 0.0f);
	float fFOV;

	// Camera nodes are after the mesh and light nodes in the array.
	// We grab camera num 0 (the only one in the scene)
	const int g_ui32Camera = 0;
	int i32CamID = m_Scene.pNode[m_Scene.nNumMeshNode + m_Scene.nNumLight + g_ui32Camera].nIdx;

	// Get the camera position and target 
	if(m_Scene.pCamera[i32CamID].nIdxTarget != -1) // Does the camera have a target?
		m_Scene.GetCameraPos( vFrom, vTo, g_ui32Camera); // vTo is taken from the target node.
	else
		m_Scene.GetCamera( vFrom, vTo, vUp, g_ui32Camera); // vTo is calculated from the rotation.

	// Calculate the FOV depending of the screen dimensions so everything fit in view
	// regardless whether the screen is rotated or not.
	// if the aspect ratio is different than 640x480 adapt FOV so the scene still looks correct.
	float fRatioWoverH = (480.0f/640.0f) * ((!bRotate) ? (float)PVRShellGet(prefWidth)/(float)PVRShellGet(prefHeight) :  (float)PVRShellGet(prefHeight)/(float)PVRShellGet(prefWidth));
	
	fFOV = m_Scene.pCamera[i32CamID].fFOV / fRatioWoverH;

	// We can build the model view matrix from the camera position, target and an up vector.
	m_mView = PVRTMat4::LookAtRH(vFrom, vTo, vUp);

	// Calculate the projection matrix.
	m_mProjection = PVRTMat4::PerspectiveFovRH(fFOV, (float)PVRShellGet(prefWidth)/(float)PVRShellGet(prefHeight), 	m_Scene.pCamera[i32CamID].fNear, m_Scene.pCamera[i32CamID].fFar, PVRTMat4::OGL, bRotate);

	return true;
}

/*!****************************************************************************
 @Function		RenderScene
 @Return		bool		true if no error occured
 @Description	Main rendering loop function of the program. The shell will
				call this function every frame.
				eglSwapBuffers() will be performed by PVRShell automatically.
				PVRShell will also manage important OS events.
				Will also manage relevent OS events. The user has access to
				these events through an abstraction layer provided by PVRShell.
******************************************************************************/
bool OGLES3Skinning::RenderScene()
{
	// Clear the color and depth buffer
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

	// Use shader program
	glUseProgram(m_ShaderProgram.uiId);
	glActiveTexture(GL_TEXTURE0);

	/*
		Calculates the frame number to animate in a time-based manner.
		Uses the shell function PVRShellGetTime() to get the time in milliseconds.
	*/
	unsigned long iTime = PVRShellGetTime();

	if(iTime > m_iTimePrev)
	{
		float fDelta = (float) (iTime - m_iTimePrev);
		m_fFrame += fDelta * g_fDemoFrameRate;

		// Modify the transformation matrix if it is needed
		bool bRebuildTransformation = false;

		if(PVRShellIsKeyPressed(PVRShellKeyNameRIGHT))
		{
			m_fAngle -= 0.03f;

			if(m_fAngle < PVRT_TWO_PIf)
				m_fAngle += PVRT_TWO_PIf;

			bRebuildTransformation = true;
		}

		if(PVRShellIsKeyPressed(PVRShellKeyNameLEFT))
		{
			m_fAngle += 0.03f;

			if(m_fAngle > PVRT_TWO_PIf)
				m_fAngle -= PVRT_TWO_PIf;

			bRebuildTransformation = true;
		}

		if(PVRShellIsKeyPressed(PVRShellKeyNameUP))
		{
			m_fDistance -= 10.0f;

			if(m_fDistance < -500.0f)
				m_fDistance = -500.0f;

			bRebuildTransformation = true;
		}

		if(PVRShellIsKeyPressed(PVRShellKeyNameDOWN))
		{
			m_fDistance += 10.0f;

			if(m_fDistance > 200.0f)
				m_fDistance = 200.0f;

			bRebuildTransformation = true;
		}

		if(bRebuildTransformation)
			m_Transform = PVRTMat4::Translation(0,0, m_fDistance) * PVRTMat4::RotationY(m_fAngle);

	}

	m_iTimePrev	= iTime;

	if(m_fFrame > m_Scene.nNumFrame - 1)
		m_fFrame = 0;

	// Set the scene animation to the current frame
	m_Scene.SetFrame(m_fFrame);

	/*
		Set up camera
	*/
	PVRTVec3	vFrom, vTo, vUp(0, 1, 0);
	PVRTMat4 mView, mProjection;
	float fFOV;

	// We can get the camera position, target and field of view (fov) with GetCameraPos()
	fFOV = m_Scene.GetCamera(vFrom, vTo, vUp, 0);

	/*
		We can build the model view matrix from the camera position, target and an up vector.
		For this we use PVRTMat4::LookAtRH().
	*/
//.........这里部分代码省略.........

/*!****************************************************************************
 @Function		InitView
 @Return		bool		true if no error occurred
 @Description	Code in InitView() will be called by PVRShell upon
				initialization or after a change in the rendering context.
				Used to initialize variables that are dependent on the rendering
				context (e.g. textures, vertex buffers, etc.)
******************************************************************************/
bool OGLES3DisplacementMap::InitView()
{
	CPVRTString ErrorStr;

	/*
		Initialize VBO data
	*/
	if(!LoadVbos(&ErrorStr))
	{
		PVRShellSet(prefExitMessage, ErrorStr.c_str());
		return false;
	}

	/*
		Load textures
	*/
	if(!LoadTextures(&ErrorStr))
	{
		PVRShellSet(prefExitMessage, ErrorStr.c_str());
		return false;
	}

	/*
		Load and compile the shaders & link programs
	*/
	if(!LoadShaders(&ErrorStr))
	{
		PVRShellSet(prefExitMessage, ErrorStr.c_str());
		return false;
	}

	/*
		Initialize Print3D
	*/
	bool bRotate = PVRShellGet(prefIsRotated) && PVRShellGet(prefFullScreen);

	if(m_Print3D.SetTextures(0,PVRShellGet(prefWidth),PVRShellGet(prefHeight), bRotate) != PVR_SUCCESS)
	{
		PVRShellSet(prefExitMessage, "ERROR: Cannot initialise Print3D\n");
		return false;
	}

	/*
		Set OpenGL ES render states needed for this training course
	*/
	// Enable backface culling and depth test
	glCullFace(GL_BACK);
	glEnable(GL_CULL_FACE);

	glEnable(GL_DEPTH_TEST);

	// Use a nice bright blue as clear colour
	glClearColor(0.6f, 0.8f, 1.0f, 1.0f);

	//Get the direction of the first light from the scene.
	m_LightDir = m_Scene.GetLightDirection(0);

	// For direction vectors, w should be 0
	m_LightDir.w = 0.0f;


	//	Set up the view and projection matrices from the camera
	PVRTVec3	vFrom, vTo(0.0f), vUp(0.0f, 1.0f, 0.0f);
	float fFOV;

	// Setup the camera

	// Camera nodes are after the mesh and light nodes in the array
	int i32CamID = m_Scene.pNode[m_Scene.nNumMeshNode + m_Scene.nNumLight + g_ui32Camera].nIdx;

	// Get the camera position, target and field of view (fov)
	if(m_Scene.pCamera[i32CamID].nIdxTarget != -1) // Does the camera have a target?
		fFOV = m_Scene.GetCameraPos( vFrom, vTo, g_ui32Camera); // vTo is taken from the target node
	else
		fFOV = m_Scene.GetCamera( vFrom, vTo, vUp, g_ui32Camera); // vTo is calculated from the rotation

	// We can build the model view matrix from the camera position, target and an up vector.
	// For this we usePVRTMat4LookAtRH()
	m_View = PVRTMat4::LookAtRH(vFrom, vTo, vUp);

	// Calculate the projection matrix
	m_Projection = PVRTMat4::PerspectiveFovRH(fFOV, (float)PVRShellGet(prefWidth)/(float)PVRShellGet(prefHeight), g_fCameraNear, g_fCameraFar, PVRTMat4::OGL, bRotate);

	// Initialize variables used for the animation
	m_ulTimePrev = PVRShellGetTime();

	return true;
}