troubles with glVertexAttribPointer

Hi,

I’m trying to render a robot which has 7 joints. Each joint is an object called “Joint”. I load the vertices correctly but I don’t know why I can just see the first joint. I new in openGL so I don’t understand very well if my calls are correct or not and the reason why…

Here you can check my code:

vertexArray is the array where I put my vertexs points previously.

GLuint vertexs; 
glGenBuffers(1,&vertexs); 
glBindBuffer(GL_ARRAY_BUFFER,vertexs); 
glBufferData(GL_ARRAY_BUFFER,sizeVertex*sizeof(GLfloat),vertexArray,GL_DYNAMIC_DRAW); 
glEnableVertexAttribArray(0); 
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, 0);

the render function:

void Joint::render()
{ 
glDrawArrays(GL_TRIANGLES,0,sizeVertex);
}

Can you see a problem? Thanks