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[Parrotrd]

Hey guys I'm learning C# XNA from a book I purchased, I'm making a space shooter at the moment and I can't understand this bouncing collision for the asteroids:

Code:

private void BounceAsteroids(Sprite asteroid1, Sprite asteroid2)
            {
                {
                    Vector2 cOfMass = (asteroid1.Velocity +
                        asteroid2.Velocity) / 2;

                    Vector2 normal1 = asteroid2.Center - asteroid1.Center;
                    normal1.Normalize();
                    Vector2 normal2 = asteroid1.Center - asteroid2.Center;
                    normal2.Normalize();

                    asteroid1.Velocity -= cOfMass;
                    asteroid1.Velocity =
                        Vector2.Reflect(asteroid1.Velocity, normal1);
                    asteroid1.Velocity += cOfMass;

                    asteroid2.Velocity -= cOfMass;
                    asteroid2.Velocity =
                        Vector2.Reflect(asteroid2.Velocity, normal2);
                    asteroid2.Velocity += cOfMass;
                }
            }

I've read the description in the book which tells me what the code does, I understand that and it works in the game but I can't calculate it myself so I don't understand what's happening.

If someone could give me an example using actual numbers instead of these variables I'd really appreciate it!

[increpare]

If you can't calculate it yourself, you don't understand it.

You know how conservation of momentum works?

You understand what all the methods being called in that routine are doing?

"If someone could give me an example using actual numbers instead of these variables I'd really appreciate it!"
Why can't you substitute in numbers yourself?

[st33d]

What's wrong with attaching some text to the asteroids and having them tell you what the values are doing?

The most important debugging and learning skill you have to hand in programming is getting the code to draw a diagram for you.

Understanding it comes second.

[Parrotrd]

What's wrong with attaching some text to the asteroids and having them tell you what the values are doing?

The most important debugging and learning skill you have to hand in programming is getting the code to draw a diagram for you.

Understanding it comes second.

Lol I can't believe I forgot that, I did that all the time when I was doing c++. Thanks a ton I can understand it now.