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Loading vertices in glBufferData with OpenGL ES 2.0

Im working with a parser that processes Wavefront OBJ 3D 3D objects, and I'm not quite sure that im is loading correctly in OpenGL.

So basically what I do is that I read my Wavefront OBJ files and analyze all the data.

Typically, in OpenGL ES 1.1, I perform the following operations when loading data:

glBegin(GL_TRIANGLES);
glNormal3f(normals[faces[i].normal[0]].v[0], normals[faces[i].normal[0]].v[1], normals[faces[i].normal[0]].v[2]);
glVertex3f(vertices[faces[i].vertex[0]].v[0], vertices[faces[i].vertex[0]].v[1], vertices[faces[i].vertex[0]].v[2]);
glNormal3f(normals[faces[i].normal[1]].v[0], normals[faces[i].normal[1]].v[1], normals[faces[i].normal[1]].v[2]);
glVertex3f(vertices[faces[i].vertex[1]].v[0], vertices[faces[i].vertex[1]].v[1], vertices[faces[i].vertex[1]].v[2]);
glNormal3f(normals[faces[i].normal[2]].v[0], normals[faces[i].normal[2]].v[1], normals[faces[i].normal[2]].v[2]);
glVertex3f(vertices[faces[i].vertex[2]].v[0], vertices[faces[i].vertex[2]].v[1], vertices[faces[i].vertex[2]].v[2]);
glEnd();

As for OpenGL ES 2.0, I tried following the tops with no luck:

glBufferData(GL_ARRAY_BUFFER, obj.vertices.size()*sizeof(float), &(obj.vertices[0].v), GL_STATIC_DRAW);

My data structure:

struct vertex {
    std::vector<float> v;
}

A vector vis created for each end end, s {x,y,z}.

class waveObj {
    public:
        std::vector<vertex> vertices;
        std::vector<vertex> texcoords;
        std::vector<vertex> normals;
        std::vector<vertex> parameters;
        std::vector<face> faces;
}

struct face {
    std::vector<int> vertex;
    std::vector<int> texture;
    std::vector<int> normal;
};

How can I load my data, as it was with OpenGL ES 1.1 in 2.0?

Is it also possible to load a vector ( v) rather than line items ( float x,y,z)?

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1 answer

:

  • VBO : , ..
  • VBO - .

+ :

:

  • pos, normal, texture ( OBJ ), ant IBO ( ), sinlge index.

:

map<FaceIndex, GLushort, FaceIndexComparator>::iterator 
           cacheIndex = cache.find(fi);

if (cacheIndex != cache.end()) {
    node->mIndices.push_back(cacheIndex->second);   
}
else {
    node->mPositions.push_back(positions[fi.v]);
    node->mNormals.push_back(normals[fi.n]);
    node->mTexCoords.push_back(texCoords[fi.t]);
    node->mIndices.push_back((unsigned int)node->mPositions.size()-1);

    cache[fi] = ((unsigned int)node->mPositions.size()-1);
}

:

  • pos, nomal tex cood... OBJ "f", , .
  • , node
  • ,
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