OpenGL Picking not work in NSOpenGLView - objective-c

Question

I Am trying to implement picking in a NSOpenGLView , but not works, this is the code.
I render only the objects that I need pick with no lights and I render the scene as same in normal render.
- (void)drawSeleccion
{
NSSize size = [self bounds].size;
GLuint selectBuf[16 * 4] = {0};
GLint hits;
glClearColor (0.0, 0.0, 0.0, 0.0);
glColor4f(1.0, 1.0, 1.0, 1.0);
glSelectBuffer (16 * 4, selectBuf);
glRenderMode(GL_SELECT);
/// *** Start ***
glInitNames();
glPushName(0);
// view port.
glViewport(0, 0, size.width, size.height);
// projection matrix.
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
float dist = 534;
aspectRatio = size.width / size.height;
nearDist = MAX(10, dist - 360.0);
farDist = dist + 360.0;
GLKMatrix4 m4 = GLKMatrix4MakePerspective(zoom, aspectRatio, nearDist, farDist);
glMultMatrixf(m4.m);
// Model view.
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
// I look at.
GLKMatrix4 glm = GLKMatrix4MakeLookAt(0, dist, 0, 0, 0, 0, 0, 0, 1);
glMultMatrixf(glm.m);
// rotate viewPort.
glRotated(rotate_x, 1, 0, 0);
glRotated(rotate_z, 0, 0, 1);
glTranslated(translate_x - frente * 0.5, fondo * -0.5, translate_z - alto * 0.5);
/// render model....
glPushMatrix();
for (int volNo = 0; volNo < [self.modeloOptimo.arr_volumenes count]; volNo++) {
VolumenOptimo *volOp = self.modeloOptimo.arr_volumenes[volNo];
glLoadName(volNo);
volOp->verProblemas = false;
[volOp drawVolumen];
}
glPopName();
glPopMatrix();
// Flush view.
glFlush();
hits = glRenderMode(GL_RENDER);
processHits (hits, selectBuf);
} // Fin de drawRect.
Always hits = 0, and selectBuf is empty.
Any idea. thanks