Phong lightning model illuminate corners

Question

I am trying to implement the phong lightning model in this cpp framework.

The Diffusion works fine but the specular seems to lightning the sphere corners...im not really sure why, because the formular seems to be correct. Has someone an idea?

Actually Output:

My Code looks like this:

Material *material = obj->material;            //the hit objects material
Point hit = ray.at(min_t);                     //the hit point
Vector N = obj->normal(hit);                   //the normal at hit point
Vector V = -ray.D;                             //the view vector

Color color = material->color;
double colorFactor = material->ka;

for( size_t i = 0; i < numLights ; ++i)
{
    Vector lightsVector = hit - lights[i]->position;
    lightsVector.normalize();
    Vector vectorReflection = (2*(N.dot(lightsVector))*N) - lightsVector;
    vectorReflection.normalize();
    double diffusion = std::max<double>(0.0,-material->kd*(lightsVector.dot(N)));
    double specular =  material->ks*pow(std::max<double>(0.0,vectorReflection.dot(V.normalized())),material->n);
    std::cout << specular << std::endl;
    colorFactor +=  diffusion + specular;
}
color *=colorFactor;

i am very thankful for any hint you can give me...

inverting the reflection doesnt affect anything...still the same image — Ditscheridou, Oct 15 '17 at 15:06
where are the lights relative to your spheres? maybe an overhead sketch or something so we can visualize the geometry a bit — Daniel A. Thompson, Oct 16 '17 at 15:16
Isn't your `lightsVector` inverted, because doing `lightposition - hitpoint` gives you the direction from the `hit point` towards the `light source`. What @Rabbid76 said is correct as well. — gallickgunner, Oct 26 '17 at 14:10

Phong lightning model illuminate corners

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