stdmeshimporter.cpp

来自「ROBOCUP 仿真3D server 源码」· C++ 代码 · 共 437 行 · 第 1/2 页

    mesh->SetPos(pos,gNumBoxVertices);

    shared_array<float> normals(new float[gNumBoxVertices*3]);
    memcpy(normals.get(),gBoxNormals,gNumBoxVertices*3*sizeof(float));
    mesh->SetNormals(normals);

    shared_array<float> tex(new float[gNumBoxVertices*3]);
    memcpy(tex.get(), gBoxTexCoords,gNumBoxVertices*3*sizeof(float));
    mesh->SetTexCoords(tex);

    shared_ptr<IndexBuffer> idx(new IndexBuffer());
    idx->Cache(gNumBoxFaces*3,gBoxFaces);
    mesh->AddFace(idx);

    return mesh;
}

//
// unit capped cylinder
//
static void AddVertex(float** at, float x, float y, float z)
{
    (**at) = x; ++(*at);
    (**at) = y; ++(*at);
    (**at) = z; ++(*at);
}

std::string StdMeshImporter::MangleName (const string& name, const ParameterList& parameter)
{
    if (
        (name != gCCylinderStr) ||
        (parameter.GetSize() < 2)
        )
        {
            return name;
        }

    stringstream ss;
    ss << gCCylinderStr;

    float radius;
    if (parameter.GetValue(parameter[0],radius))
        {
            ss << "R=" << radius;
        }

    float length;
    if (parameter.GetValue(parameter[1],length))
        {
            ss << "L=" << length;
        }

    return ss.str();
}

shared_ptr<TriMesh> StdMeshImporter::UnitCCylinder(const ParameterList& parameter)
{
    //
    // code adapted from ODE's drawstuff lib
    //

    // generated capped clinder with r=1 and l=1
    float ccRadius = 1;
    float ccLength = 1;

    GetLog()->Debug()
        << "(StdMeshImporter::UnitCCylinder) paramSize="
        << parameter.GetSize() << "\n";
    if (parameter.GetSize() >= 2)
        {
            parameter.GetValue(parameter[0],ccRadius);
            parameter.GetValue(parameter[1],ccLength);
        }

    // number of sides to the cylinder (divisible by 4):
    const int capped_cylinder_quality = 3;
    const int n = capped_cylinder_quality*4;

    int innerLoop = (n+1);
    int numVertices = innerLoop * 2;
    numVertices += (innerLoop * (n/4) * 2);
    numVertices += (innerLoop * (n/4) * 2);

    shared_array<float> pos(new float[numVertices * 3]);
    shared_array<float> normals(new float[numVertices * 3]);
    float* cVert = pos.get();
    float* cNormal = normals.get();

    int i,j;
    float tmp,nx,start_nx,start_ny;

    float l = ccLength * 0.5;
    float a = g2PI / n;
    float sa = gSin(a);
    float ca = gCos(a);

    // draw cylinder body

    // normal vector = (0,ny,nz)
    float ny = 1;
    float nz = 0;

    for (i=0; i<=n; ++i)
        {
            AddVertex(&cNormal,ny,nz,0);
            AddVertex(&cVert,ny*ccRadius,nz*ccRadius,l);
            AddVertex(&cNormal,ny,nz,0);
            AddVertex(&cVert,ny*ccRadius,nz*ccRadius,-l);

            // rotate ny,nz
            tmp = ca * ny - sa * nz;
            nz = sa*ny + ca*nz;
            ny = tmp;
        }

    // draw first cylinder cap
    start_nx = 0;
    start_ny = 1;

    for (j=0; j<(n/4); ++j)
        {
            // get start_n2 = rotated start_n
            float start_nx2 =  ca*start_nx + sa*start_ny;
            float start_ny2 = -sa*start_nx + ca*start_ny;

            // get n=start_n and n2=start_n2
            nx = start_nx;
            ny = start_ny;
            nz = 0;
            float nx2 = start_nx2;
            float ny2 = start_ny2;
            float nz2 = 0;

            for (i=0; i<=n; i++)
                {
                    AddVertex(&cNormal,ny2,nz2,nx2);
                    AddVertex(&cVert,ny2*ccRadius,nz2*ccRadius,l+nx2*ccRadius);
                    AddVertex(&cNormal,ny,nz,nx);
                    AddVertex(&cVert,ny*ccRadius,nz*ccRadius,l+nx*ccRadius);

                    // rotate n,n2
                    tmp = ca*ny - sa*nz;
                    nz = sa*ny + ca*nz;
                    ny = tmp;
                    tmp = ca*ny2- sa*nz2;
                    nz2 = sa*ny2 + ca*nz2;
                    ny2 = tmp;
                }

            start_nx = start_nx2;
            start_ny = start_ny2;
        }

    // draw second cylinder cap
    start_nx = 0;
    start_ny = 1;

    for (j=0; j<(n/4); j++)
        {
            // get start_n2 = rotated start_n
            float start_nx2 = ca*start_nx - sa*start_ny;
            float start_ny2 = sa*start_nx + ca*start_ny;

            // get n=start_n and n2=start_n2
            nx = start_nx; ny = start_ny; nz = 0;
            float nx2 = start_nx2;
            float ny2 = start_ny2;
            float nz2 = 0;

            for (i=0; i<=n; i++)
                {
                    AddVertex(&cNormal,ny,nz,nx);
                    AddVertex(&cVert,ny*ccRadius,nz*ccRadius,-l+nx*ccRadius);
                    AddVertex(&cNormal,ny2,nz2,nx2);
                    AddVertex(&cVert,ny2*ccRadius,nz2*ccRadius,-l+nx2*ccRadius);
                    // rotate n,n2
                    tmp = ca*ny - sa*nz;
                    nz = sa*ny + ca*nz;
                    ny = tmp;
                    tmp = ca*ny2- sa*nz2;
                    nz2 = sa*ny2 + ca*nz2;
                    ny2 = tmp;
                }

            start_nx = start_nx2;
            start_ny = start_ny2;
        }

    shared_ptr<IndexBuffer> idx(new IndexBuffer());
    // triangle strip -> triangles
    int numFaces = (numVertices - 2);
    idx->EnsureFit(numFaces*3);

    for (i=0;i<numFaces;++i)
        {
            if (i%2)
                {
                    idx->Cache(i+1);
                    idx->Cache(i);
                    idx->Cache(i+2);
                } else
                    {
                        idx->Cache(i);
                        idx->Cache(i+1);
                        idx->Cache(i+2);
                    }
        }

    shared_ptr<TriMesh> mesh(new TriMesh());
    mesh->SetPos(pos,numVertices);
    mesh->SetNormals(normals);
    mesh->AddFace(idx);
    mesh->SetName(MangleName(gCCylinderStr,parameter));

    return mesh;
}