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GLKit, Opengl ES 2.0 Picking Ray for select object

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Solution for picking

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GLKVector4 normalisedVector = GLKVector4Make((2 * position.x / self.view.bounds.size.width - 1),
                                                 (2 * (self.view.bounds.size.height-position.y) / self.view.bounds.size.height - 1),  
                                                   -1,
                                                   1);

GLKMatrix4 inversedMatrix = GLKMatrix4Invert(_modelViewProjectionMatrix, nil);

GLKVector4 near_point = GLKMatrix4MultiplyVector4(inversedMatrix, normalisedVector);

near_point.v[3] = 1.0/near_point.v[3];
near_point = GLKVector4Make(near_point.v[0]*near_point.v[3], near_point.v[1]*near_point.v[3], near_point.v[2]*near_point.v[3], 1);

normalisedVector.z = 1.0;
GLKVector4 far_point = GLKMatrix4MultiplyVector4(inversedMatrix, normalisedVector);

far_point.v[3] = 1.0/far_point.v[3];
far_point = GLKVector4Make(far_point.v[0]*far_point.v[3], far_point.v[1]*far_point.v[3], far_point.v[2]*far_point.v[3], 1);

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