C++ VertexDeclaration类代码示例

	//-------------------------------------------------------------------------------//
	void OverlayPanelElement::initialise(const String& texName, float width, float height, float left, float top)
	{
		mTexture = TextureMgr::getSingletonPtr()->getByName(texName);
		setSize(width, height);
		setPosition(left, top);
		mIsVisible = true;

		if(!mIsInitialised)
		{
			mRenderData.vertexData = TITAN_NEW VertexData();
			VertexDeclaration* decl = mRenderData.vertexData->vertexDecl;
			decl->addElement(0,0, VET_FLOAT3, VES_POSITION);

			mRenderData.vertexData->vertexStart = 0;
			mRenderData.vertexData->vertexCount = 4;

			VertexBufferPtr vbuf = HardwareBufferMgr::getSingletonPtr()->createVertexBuffer(decl->getVertexSize(0), mRenderData.vertexData->vertexCount,
				HardwareBuffer::HBU_STATIC_WRITE_ONLY, false);
			mRenderData.vertexData->vertexBufferBinding->setBinding(0, vbuf);

			mRenderData.useIndex = false;
			mRenderData.operationType = OT_TRIANGLE_STRIP;

			mIsInitialised = true;
		}

		notifyGeometryOld();
	}

	//-----------------------------------------------------------------------
	void BillboardChain::setupVertexDeclaration(void)
	{
		if (mVertexDeclDirty)
		{
			VertexDeclaration* decl = mVertexData->vertexDeclaration;
			decl->removeAllElements();

			size_t offset = 0;
			// Add a description for the buffer of the positions of the vertices
			decl->addElement(0, offset, VET_FLOAT3, VES_POSITION);
			offset += VertexElement::getTypeSize(VET_FLOAT3);

			if (mUseVertexColour)
			{
				decl->addElement(0, offset, VET_COLOUR, VES_DIFFUSE);
				offset += VertexElement::getTypeSize(VET_COLOUR);
			}

			if (mUseTexCoords)
			{
				decl->addElement(0, offset, VET_FLOAT2, VES_TEXTURE_COORDINATES);
			}

			if (!mUseTexCoords && !mUseVertexColour)
			{
				LogManager::getSingleton().logMessage(
					"Error - BillboardChain '" + mName + "' is using neither "
					"texture coordinates or vertex colours; it will not be "
					"visible on some rendering APIs so you should change this "
					"so you use one or the other.");
			}
			mVertexDeclDirty = false;
		}
	}

    //---------------------------------------------------------------------
    void BorderPanelOverlayElement::initialise(void)
    {
        bool init = !mInitialised;

        // init mRenderOp2 before calling superclass, as virtual _restoreManualHardwareResources would be called within
        if (init)
        {
            // Setup render op in advance
            mRenderOp2.vertexData = OGRE_NEW VertexData();
            mRenderOp2.vertexData->vertexCount = 4 * 8; // 8 cells, can't necessarily share vertices cos
                                                        // texcoords may differ
            mRenderOp2.vertexData->vertexStart = 0;

            // Vertex declaration
            VertexDeclaration* decl = mRenderOp2.vertexData->vertexDeclaration;
            // Position and texture coords each have their own buffers to allow
            // each to be edited separately with the discard flag
            decl->addElement(POSITION_BINDING, 0, VET_FLOAT3, VES_POSITION);
            decl->addElement(TEXCOORD_BINDING, 0, VET_FLOAT2, VES_TEXTURE_COORDINATES, 0);

            // Index data
            mRenderOp2.operationType = RenderOperation::OT_TRIANGLE_LIST;
            mRenderOp2.useIndexes = true;
            mRenderOp2.indexData = OGRE_NEW IndexData();
            mRenderOp2.indexData->indexCount = 8 * 6;
            mRenderOp2.indexData->indexStart = 0;
            mRenderOp2.useGlobalInstancingVertexBufferIsAvailable = false;

            // Create sub-object for rendering border
            mBorderRenderable = OGRE_NEW BorderRenderable(this);
        }

        // superclass will handle the interior panel area and call _restoreManualHardwareResources
        PanelOverlayElement::initialise();
    }

    void WireBoundingBox::_initWireBoundingBox()
    {
        mRenderOp.vertexData = OGRE_NEW VertexData();

        mRenderOp.indexData = 0;
        mRenderOp.vertexData->vertexCount = 24; 
        mRenderOp.vertexData->vertexStart = 0; 
        mRenderOp.operationType = RenderOperation::OT_LINE_LIST; 
        mRenderOp.useIndexes = false; 
        mRenderOp.useGlobalInstancingVertexBufferIsAvailable = false;

        VertexDeclaration* decl = mRenderOp.vertexData->vertexDeclaration;
        VertexBufferBinding* bind = mRenderOp.vertexData->vertexBufferBinding;

        decl->addElement(POSITION_BINDING, 0, VET_FLOAT3, VES_POSITION);


        HardwareVertexBufferSharedPtr vbuf = 
            HardwareBufferManager::getSingleton().createVertexBuffer(
                decl->getVertexSize(POSITION_BINDING),
                mRenderOp.vertexData->vertexCount,
                HardwareBuffer::HBU_STATIC_WRITE_ONLY);

        // Bind buffer
        bind->setBinding(POSITION_BINDING, vbuf);

        // set basic white material
        this->setMaterial("BaseWhiteNoLighting");


        
    }

void GeomUtils::createQuad(VertexData*& vertexData)
{
	assert(vertexData);

	vertexData->vertexCount = 4;
	vertexData->vertexStart = 0;

	VertexDeclaration* vertexDecl = vertexData->vertexDeclaration;
	VertexBufferBinding* bind = vertexData->vertexBufferBinding;

	vertexDecl->addElement(0, 0, VET_FLOAT3, VES_POSITION);

	HardwareVertexBufferSharedPtr vbuf = 
		HardwareBufferManager::getSingleton().createVertexBuffer(
		vertexDecl->getVertexSize(0),
		vertexData->vertexCount,
		HardwareBuffer::HBU_STATIC_WRITE_ONLY);

	// Bind buffer
	bind->setBinding(0, vbuf);
	// Upload data
	float data[]={
		-1,1,-1,  // corner 1
		-1,-1,-1, // corner 2
		1,1,-1,   // corner 3
		1,-1,-1}; // corner 4
		vbuf->writeData(0, sizeof(data), data, true);
}

VertexDeclaration* VertexBufferManager::CreateVertexDeclaration( const std::string &name, VertexPointer *pointers, size_t count )
{
	VertexDeclaration *pDecl = new VertexDeclaration();
	pDecl->AddPointers( pointers, count );
	mVertexDeclarations[ name ] = pDecl;
	return pDecl;
}

    //---------------------------------------------------------------------
    void PanelOverlayElement::initialise(void)
    {
        bool init = !mInitialised;

        OverlayContainer::initialise();
        if (init)
        {
            // Setup render op in advance
            mRenderOp.vertexData = OGRE_NEW VertexData();
            // Vertex declaration: 1 position, add texcoords later depending on #layers
            // Create as separate buffers so we can lock & discard separately
            VertexDeclaration* decl = mRenderOp.vertexData->vertexDeclaration;
            decl->addElement(POSITION_BINDING, 0, VET_FLOAT3, VES_POSITION);

            // Basic vertex data
            mRenderOp.vertexData->vertexStart = 0;
            mRenderOp.vertexData->vertexCount = 4;
            // No indexes & issue as a strip
            mRenderOp.useIndexes = false;
            mRenderOp.operationType = RenderOperation::OT_TRIANGLE_STRIP;
            mRenderOp.useGlobalInstancingVertexBufferIsAvailable = false;

            mInitialised = true;

            _restoreManualHardwareResources();
        }
    }

    void TextAreaOverlayElement::initialise(void)
    {
        if (!mInitialised)
        {
            // Set up the render op
            // Combine positions and texture coords since they tend to change together
            // since character sizes are different
            mRenderOp.vertexData = OGRE_NEW VertexData();
            VertexDeclaration* decl = mRenderOp.vertexData->vertexDeclaration;
            size_t offset = 0;
            // Positions
            decl->addElement(POS_TEX_BINDING, offset, VET_FLOAT3, VES_POSITION);
            offset += VertexElement::getTypeSize(VET_FLOAT3);
            // Texcoords
            decl->addElement(POS_TEX_BINDING, offset, VET_FLOAT2, VES_TEXTURE_COORDINATES, 0);
            // Colours - store these in a separate buffer because they change less often
            decl->addElement(COLOUR_BINDING, 0, VET_COLOUR, VES_DIFFUSE);

            mRenderOp.operationType = RenderOperation::OT_TRIANGLE_LIST;
            mRenderOp.useIndexes = false;
            mRenderOp.vertexData->vertexStart = 0;
            mRenderOp.useGlobalInstancingVertexBufferIsAvailable = false;
            // Vertex buffer will be created in checkMemoryAllocation
            mRenderOp.srcRenderable = this;
            checkMemoryAllocation( DEFAULT_INITIAL_CHARS );

            mInitialised = true;
        }

    }

    bool areCompatible
    (
        const VertexDeclaration &u, 
        const VertexDeclaration &v
    )
    {
        if( u.count() != v.count() )
            return false;

        for(std::size_t i(0); i<u.count(); ++i)
        {
            bool have = false;

            for(std::size_t j(0); j<v.count(); ++j)
            {
                if(u[i].getSemantic() == v[j].getSemantic() && u[i].getType() == v[j].getType() )
                    have = true;

                if(have)
                    break;
            }

            if(!have)
                return false;
        }

        return true;
    }

    //---------------------------------------------------------------------
    void TextAreaOverlayElement::_restoreManualHardwareResources()
    {
        if(!mInitialised)
            return;

        // 6 verts per char since we're doing tri lists without indexes
        // Allocate space for positions & texture coords
        // Note - mRenderOp.vertexData->vertexCount will be less than allocatedVertexCount
        size_t allocatedVertexCount = mAllocSize * 6;
        VertexDeclaration* decl = mRenderOp.vertexData->vertexDeclaration;
        VertexBufferBinding* bind = mRenderOp.vertexData->vertexBufferBinding;

        // Create dynamic since text tends to change a lot
        // positions & texcoords
        HardwareVertexBufferSharedPtr vbuf = 
            HardwareBufferManager::getSingleton().
                createVertexBuffer(
                    decl->getVertexSize(POS_TEX_BINDING), 
                    allocatedVertexCount,
                    HardwareBuffer::HBU_DYNAMIC_WRITE_ONLY);
        bind->setBinding(POS_TEX_BINDING, vbuf);

        // colours
        vbuf = HardwareBufferManager::getSingleton().
                createVertexBuffer(
                    decl->getVertexSize(COLOUR_BINDING), 
                    allocatedVertexCount,
                    HardwareBuffer::HBU_DYNAMIC_WRITE_ONLY);
        bind->setBinding(COLOUR_BINDING, vbuf);

        // Buffers are restored, but with trash within
        mGeomPositionsOutOfDate = true;
        mGeomUVsOutOfDate = true;
        mColoursChanged = true;
    }

    //---------------------------------------------------------------------
    void PanelOverlayElement::initialise(void)
    {
		bool init = !mInitialised;

		OverlayContainer::initialise();
		if (init)
		{
			// Setup render op in advance
			mRenderOp.vertexData = OGRE_NEW VertexData();
			// Vertex declaration: 1 position, add texcoords later depending on #layers
			// Create as separate buffers so we can lock & discard separately
			VertexDeclaration* decl = mRenderOp.vertexData->vertexDeclaration;
			decl->addElement(POSITION_BINDING, 0, VET_FLOAT3, VES_POSITION);

			// Basic vertex data
			mRenderOp.vertexData->vertexStart = 0;
			mRenderOp.vertexData->vertexCount = 4;

			// Vertex buffer #1
			HardwareVertexBufferSharedPtr vbuf =
				HardwareBufferManager::getSingleton().createVertexBuffer(
				decl->getVertexSize(POSITION_BINDING), mRenderOp.vertexData->vertexCount,
				HardwareBuffer::HBU_STATIC_WRITE_ONLY// mostly static except during resizing
				);
			// Bind buffer
			mRenderOp.vertexData->vertexBufferBinding->setBinding(POSITION_BINDING, vbuf);

			// No indexes & issue as a strip
			mRenderOp.useIndexes = false;
			mRenderOp.operationType = RenderOperation::OT_TRIANGLE_STRIP;

			mInitialised = true;
		}
    }

void Line3D::drawLines(void)
{
   if(mDrawn)
      return;
   else
      mDrawn = true;

   // Initialization stuff
   mRenderOp.indexData = 0;
   mRenderOp.vertexData->vertexCount = mPoints.size();
   mRenderOp.vertexData->vertexStart = 0;
   mRenderOp.operationType = RenderOperation::OT_LINE_LIST; // OT_LINE_LIST, OT_LINE_STRIP
   mRenderOp.useIndexes = false;

   VertexDeclaration *decl = mRenderOp.vertexData->vertexDeclaration;
   VertexBufferBinding *bind = mRenderOp.vertexData->vertexBufferBinding;

   decl->addElement(POSITION_BINDING, 0, VET_FLOAT3, VES_POSITION);

   HardwareVertexBufferSharedPtr vbuf =
      HardwareBufferManager::getSingleton().createVertexBuffer(
         decl->getVertexSize(POSITION_BINDING),
         mRenderOp.vertexData->vertexCount,
         HardwareBuffer::HBU_STATIC_WRITE_ONLY);

   bind->setBinding(POSITION_BINDING, vbuf);

   // Drawing stuff
   int size = mPoints.size();
   Vector3 vaabMin = mPoints[0];
   Vector3 vaabMax = mPoints[0];

   Real *prPos = static_cast<Real*>(vbuf->lock(HardwareBuffer::HBL_DISCARD));

   for(int i = 0; i < size; i++)
   {
      *prPos++ = mPoints[i].x;
      *prPos++ = mPoints[i].y;
      *prPos++ = mPoints[i].z;

      if(mPoints[i].x < vaabMin.x)
         vaabMin.x = mPoints[i].x;
      if(mPoints[i].y < vaabMin.y)
         vaabMin.y = mPoints[i].y;
      if(mPoints[i].z < vaabMin.z)
         vaabMin.z = mPoints[i].z;

      if(mPoints[i].x > vaabMax.x)
         vaabMax.x = mPoints[i].x;
      if(mPoints[i].y > vaabMax.y)
         vaabMax.y = mPoints[i].y;
      if(mPoints[i].z > vaabMax.z)
         vaabMax.z = mPoints[i].z;
   }

   vbuf->unlock();

   mBox.setExtents(vaabMin, vaabMax);
}

	void VertexBuffer::doadvance()
	{
		VertexDeclaration* vd = m_vertexdeclaration;
		if( vd )
		{
			vd->advance();
		}
	}

VertexDeclaration TerrainManager::GetTempMeshDecl()
{
	VertexDeclaration decl;
	decl.Add( VertexTypes::VEC3 ); // pos
	decl.Add( VertexTypes::VEC3 ); // normal
	decl.Add( VertexTypes::VEC2 ); // uv 
	return decl;
}

	//---------------------------------------------------------------------
	void PrefabFactory::createPlane(Mesh* mesh)
	{
		SubMesh* sub = mesh->createSubMesh();
		float vertices[32] = {
			-100, -100, 0,	// pos
			0,0,1,			// normal
			0,1,			// texcoord
			100, -100, 0,
			0,0,1,
			1,1,
			100,  100, 0,
			0,0,1,
			1,0,
			-100,  100, 0 ,
			0,0,1,
			0,0 
		};
		mesh->sharedVertexData = OGRE_NEW VertexData();
		mesh->sharedVertexData->vertexCount = 4;
		VertexDeclaration* decl = mesh->sharedVertexData->vertexDeclaration;
		VertexBufferBinding* bind = mesh->sharedVertexData->vertexBufferBinding;

		size_t offset = 0;
		decl->addElement(0, offset, VET_FLOAT3, VES_POSITION);
		offset += VertexElement::getTypeSize(VET_FLOAT3);
		decl->addElement(0, offset, VET_FLOAT3, VES_NORMAL);
		offset += VertexElement::getTypeSize(VET_FLOAT3);
		decl->addElement(0, offset, VET_FLOAT2, VES_TEXTURE_COORDINATES, 0);
		offset += VertexElement::getTypeSize(VET_FLOAT2);

		HardwareVertexBufferSharedPtr vbuf = 
			HardwareBufferManager::getSingleton().createVertexBuffer(
			offset, 4, HardwareBuffer::HBU_STATIC_WRITE_ONLY);
		bind->setBinding(0, vbuf);

		vbuf->writeData(0, vbuf->getSizeInBytes(), vertices, true);

		sub->useSharedVertices = true;
		HardwareIndexBufferSharedPtr ibuf = HardwareBufferManager::getSingleton().
			createIndexBuffer(
			HardwareIndexBuffer::IT_16BIT, 
			6, 
			HardwareBuffer::HBU_STATIC_WRITE_ONLY);

		unsigned short faces[6] = {0,1,2,
			0,2,3 };
		sub->indexData->indexBuffer = ibuf;
		sub->indexData->indexCount = 6;
		sub->indexData->indexStart =0;
		ibuf->writeData(0, ibuf->getSizeInBytes(), faces, true);

		mesh->_setBounds(AxisAlignedBox(-100,-100,0,100,100,0), true);
		mesh->_setBoundingSphereRadius(Math::Sqrt(100*100+100*100));
	}