白云哥

魔獸mdx文件導(dǎo)出為Ogre Mesh的小進展

    最近一直在試圖把魔獸3的mdx文件轉(zhuǎn)為Ogre Mesh，學(xué)習(xí)一下基礎(chǔ)的3D編程。Ogre Mesh的導(dǎo)出在很久之前也曾試圖做過，并且還把WOW的m2模型以及WMO模型導(dǎo)入到了Max中，但是只做到了骨架的導(dǎo)入，動畫數(shù)據(jù)始終出不來，于是放棄。

    這次依然是碰到這里的問題，導(dǎo)出靜態(tài)的Mesh很快就完成，包括模型與材質(zhì)，代碼也比較簡單。

// 模型數(shù)據(jù)
bool ModelLoaderMdx::loadGeosets(Ogre::MeshPtr model, MdxDataStreamPtr dataStream, int size)
{
    unsigned int index = 0;
    while(size > 0)
    {
        int geosetSize = dataStream->read<int>();
        size -= geosetSize;

        Ogre::String meshName = m_modelName + Ogre::String("_sub_") + Ogre::StringConverter::toString(index++);
        Ogre::SubMesh* subMesh = model->createSubMesh(meshName);
    
        // 硬件緩沖編號
        // 分別為頂點坐標(biāo) 法線 貼圖坐標(biāo)
#define HARDWARE_BUFFER_SOURCE_VERTEX 0
#define HARDWARE_BUFFER_SOURCE_NORMAL 1
#define HARDWARE_BUFFER_SOURCE_TEXPOS 2


        //
        // 頂點數(shù)據(jù)
        //
        if(!expectTag(dataStream, 'VRTX')) 
        {
            OGRE_EXCEPT(Ogre::Exception::ERR_INTERNAL_ERROR, "Expect VRTX data for geoset",
                "ModelLoaderMdx::loadGeosets");
        }

        unsigned int vertexCount = dataStream->read<unsigned int>();

        // 不使用共享頂點數(shù)據(jù)
        // 每個SubMesh都創(chuàng)建自己的VertexData
        subMesh->useSharedVertices = false;
        subMesh->vertexData = OGRE_NEW Ogre::VertexData();

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

        subMesh->vertexData->vertexDeclaration->addElement(
            HARDWARE_BUFFER_SOURCE_VERTEX, 0, Ogre::VET_FLOAT3, Ogre::VES_POSITION);

        size_t vertexSize = sizeof(float) * 3;
        assert(subMesh->vertexData->vertexDeclaration->getVertexSize(HARDWARE_BUFFER_SOURCE_VERTEX) == vertexSize);
        if (subMesh->vertexData->vertexDeclaration->getVertexSize(HARDWARE_BUFFER_SOURCE_VERTEX) != vertexSize)
        {
            OGRE_EXCEPT(Ogre::Exception::ERR_INTERNAL_ERROR, "VertexSize error", 
                "ModelLoaderMdx::loadGeoset");
        }

        Ogre::HardwareVertexBufferSharedPtr vertexBuffer;
        vertexBuffer = Ogre::HardwareBufferManager::getSingleton().createVertexBuffer(
            vertexSize,
            vertexCount,
            Ogre::HardwareBuffer::HBU_STATIC_WRITE_ONLY);
        void* vertexBufferData = vertexBuffer->lock(Ogre::HardwareBuffer::HBL_DISCARD);

        unsigned int vertexBufferDataPos = 0;
        for (unsigned int i = 0; i < vertexCount; ++i)
        {
            Ogre::Vector3 data(
                dataStream->read<float>(),
                dataStream->read<float>(),
                dataStream->read<float>()
                );
            transformCoord(data);
            memcpy((char*)vertexBufferData + vertexBufferDataPos, &data, sizeof(Ogre::Vector3));
            vertexBufferDataPos += sizeof(Ogre::Vector3);
        }

        vertexBuffer->unlock();
        subMesh->vertexData->vertexBufferBinding->setBinding(HARDWARE_BUFFER_SOURCE_VERTEX, vertexBuffer);


        //
        // 法線數(shù)據(jù)
        //
        if(!expectTag(dataStream, 'NRMS'))
        {
            OGRE_EXCEPT(Ogre::Exception::ERR_INTERNAL_ERROR, "Expect NRMS data for material",
                "ModelLoaderMdx::loadGeosets");
        }

        unsigned int normalCount = dataStream->read<unsigned int>();
        if(normalCount != vertexCount)
        {
            std::stringstream stream;
            stream << "Normal count mismatch, " << normalCount << " normals for " << vertexCount << " vertices)!";
            OGRE_EXCEPT(Ogre::Exception::ERR_INTERNAL_ERROR, stream.str(), 
                "ModelLoaderMdx::loadGeoset");
        }

        subMesh->vertexData->vertexDeclaration->addElement(
            HARDWARE_BUFFER_SOURCE_NORMAL, 0, Ogre::VET_FLOAT3, Ogre::VES_NORMAL);

        size_t normalSize = sizeof(float) * 3;
        assert(subMesh->vertexData->vertexDeclaration->getVertexSize(HARDWARE_BUFFER_SOURCE_NORMAL) == normalSize);
        if (subMesh->vertexData->vertexDeclaration->getVertexSize(HARDWARE_BUFFER_SOURCE_NORMAL) != normalSize)
        {
            OGRE_EXCEPT(Ogre::Exception::ERR_INTERNAL_ERROR, "NormalSize error", 
                "ModelLoaderMdx::loadGeoset");
        }

        Ogre::HardwareVertexBufferSharedPtr normalBuffer;
        normalBuffer = Ogre::HardwareBufferManager::getSingleton().createVertexBuffer(
            normalSize,
            normalCount,
            Ogre::HardwareBuffer::HBU_STATIC_WRITE_ONLY);
        void* normalBufferData = normalBuffer->lock(Ogre::HardwareBuffer::HBL_DISCARD);

        unsigned int normalBufferDataPos = 0;
        for (unsigned int i = 0; i < normalCount; ++i)
        {
            Ogre::Vector3 data(
                dataStream->read<float>(),
                dataStream->read<float>(),
                dataStream->read<float>()
                );
            transformCoord(data);
            memcpy((char*)normalBufferData + normalBufferDataPos, &data, sizeof(Ogre::Vector3));
            normalBufferDataPos += sizeof(Ogre::Vector3);
        }

        normalBuffer->unlock();
        subMesh->vertexData->vertexBufferBinding->setBinding(HARDWARE_BUFFER_SOURCE_NORMAL, normalBuffer);


…………

        //
        // 頂點索引
        //
        if(!expectTag(dataStream, 'PVTX')) 
        {
            OGRE_EXCEPT(Ogre::Exception::ERR_INTERNAL_ERROR, "Expect PVTX data for geoset",
                "ModelLoaderMdx::loadGeosets");
        }

        unsigned int indexCount = dataStream->read<unsigned int>();
        assert(totalIndexCount == indexCount);
        if (totalIndexCount != indexCount)
        {
            std::stringstream stream;
            stream << "indexCount is " << indexCount << ", but totalIndexCount for all faces is " << totalIndexCount;
            OGRE_EXCEPT(Ogre::Exception::ERR_INTERNAL_ERROR, stream.str(), 
                "ModelLoaderMdx::loadGeoset");
        }

        subMesh->indexData->indexStart = 0;
        subMesh->indexData->indexCount = indexCount;

        Ogre::HardwareIndexBufferSharedPtr indexBuffer;
        indexBuffer = Ogre::HardwareBufferManager::getSingleton().createIndexBuffer(
            Ogre::HardwareIndexBuffer::IT_16BIT,
            indexCount,
            Ogre::HardwareBuffer::HBU_STATIC_WRITE_ONLY);

        void* indexBufferData = indexBuffer->lock(Ogre::HardwareBuffer::HBL_DISCARD);
        dataStream->read(indexBufferData, indexCount * sizeof(unsigned short));

        // 三角形反轉(zhuǎn), 將原來的反面朝外
        unsigned short* tmpData = (unsigned short*)indexBufferData;
        for (unsigned int i = 0; i < indexCount; i += 3)
        {
            unsigned short tmp = tmpData[i + 1];
            tmpData[i + 1] = tmpData[i + 2];
            tmpData[i + 2] = tmp;
        }

        indexBuffer->unlock();


        subMesh->indexData->indexBuffer = indexBuffer;
        subMesh->operationType = Ogre::RenderOperation::OT_TRIANGLE_LIST;


…………

        // 材質(zhì)ID
        unsigned int materialID = dataStream->read<unsigned int>();
        Ogre::String materialName = m_modelName + Ogre::String("_") + boost::lexical_cast<Ogre::String>(materialID);
        subMesh->setMaterialName(materialName);

…………

        //
        // 貼圖坐標(biāo)
        //
        if(!expectTag(dataStream, 'UVBS')) 
        {
            OGRE_EXCEPT(Ogre::Exception::ERR_INTERNAL_ERROR, "Expect UVBS data for geoset",
                "ModelLoaderMdx::loadGeosets");
        }

        unsigned int texturePositionCount = dataStream->read<unsigned int>();
        if(texturePositionCount != vertexCount)
        {
            std::stringstream stream;
            stream << "Texture position count mismatch, " << texturePositionCount << " texture positions for " << vertexCount << " vertices)!";
            OGRE_EXCEPT(Ogre::Exception::ERR_INTERNAL_ERROR, stream.str(), 
                "ModelLoaderMdx::loadGeoset");
        }

        // TextureCoord Data
        subMesh->vertexData->vertexDeclaration->addElement(
            HARDWARE_BUFFER_SOURCE_TEXPOS, 0, Ogre::VET_FLOAT2, Ogre::VES_TEXTURE_COORDINATES);

        size_t texPosSize = sizeof(float) * 2;
        assert(subMesh->vertexData->vertexDeclaration->getVertexSize(HARDWARE_BUFFER_SOURCE_TEXPOS) == texPosSize);
        if (subMesh->vertexData->vertexDeclaration->getVertexSize(HARDWARE_BUFFER_SOURCE_TEXPOS) != texPosSize)
        {
            OGRE_EXCEPT(Ogre::Exception::ERR_INTERNAL_ERROR, "TexturePositionSize error", 
                "ModelLoaderMdx::loadGeoset");
        }

        Ogre::HardwareVertexBufferSharedPtr texPosBuffer;
        texPosBuffer = Ogre::HardwareBufferManager::getSingleton().createVertexBuffer(
            texPosSize,
            texturePositionCount,
            Ogre::HardwareBuffer::HBU_STATIC_WRITE_ONLY);
        void* texPosBufferData = texPosBuffer->lock(Ogre::HardwareBuffer::HBL_DISCARD);
        dataStream->read(texPosBufferData, texPosSize * texturePositionCount);
        texPosBuffer->unlock();
        subMesh->vertexData->vertexBufferBinding->setBinding(HARDWARE_BUFFER_SOURCE_TEXPOS, texPosBuffer);
    }

    return true;
}

    但是到了動畫數(shù)據(jù)這里問題又出來了，而且mdx模型與m2模型還有些差別，mdx模型中沒有骨骼數(shù)據(jù)，只有max中最簡單的三種變換數(shù)據(jù)，Ogre中只有MorphAnimation能夠?qū)崿F(xiàn)此種動畫。

    Ogre的MorphAnimation的第一個KeyFrame必須帶有完整的頂點信息，而mdx模型中旋轉(zhuǎn)、縮放與位移是分開的，也就是一個KeyFrame上可能只有一種變換，或者多種。而實際上在max中制作動畫的時候這三種變換也是獨立開的，Ogre的論壇上找到一篇討論有人提到了這個問題，可惜制作者的回復(fù)是MorphAnimation只實現(xiàn)到這樣……

    也確實，現(xiàn)在除了一些小物件的動畫外，主角，怪物的動畫都用skeleton了，也許MorphAnimation就快退出歷史的舞臺，在Ogre中看不到了，也不能指望會有什么改進。

    繼續(xù)實現(xiàn)之，那就只能在有KeyFrame的地方把三種變換都計算一次，然后取得最終變換后的位置數(shù)據(jù)，也就是做人工的動畫幀采樣。在War3EditorSource的基礎(chǔ)上做了些修改，終于，一幀幀的動畫計算出來了。

    不過問題依然還有很多，比如mdx模型，尤其是怪物和角色模型中大量用到了ReplacableTexture，這些需要通過讀配置文件來獲取可用的貼圖，另外模型上附帶的粒子特效、紋理動畫等都還沒有導(dǎo)出，看看這個沒有貼圖的攻擊中的蝎子，前面的路仍然很遠。

posted on 2009-08-07 22:42 白云哥 閱讀(2286) 評論(0)  編輯 收藏 引用 所屬分類: Ogre