1.- Position or vector? #
¿What is the difference between a point and a vector?
In strict math, both are the same. But when using them in practical applications, I like to distinguish between them as such:
Position:
In 3D has 3 coordinates. A single point in space
Vector:
In 3D has 3 coordinates. Direction with scale/magnitude
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1.1.- Common operations & properties #
1.1.1.- Magnitude #
The length of the vector
We apply the Pythagoras theorem
1.1.2.- Unit Vector #
A vector with length 1
All divisions can be represented as a multiplication
1.1.3.- Multiplication #
Scales the magnitude of the vector
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1.1.4.- Addition #
Moves the vector
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Moving a point through space #
What is this operation?
1.2.- Other operations #
1.2.1.- Dot product #
The cosine of the angle in-between two vectors (Also used for alignment)
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What I am looking at? #
Given a camera, and a group of points, determine the one nearest to the center of the viewport.
1.2.2.- Cross product #
Perpendicular vector with scale related to the area between the two vectors
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What is the slope? #
The engine gives you three points of collision, and you need to apply a bounce. Find the triangle and it’s normal vector.
2.- The magic hand #
Using our own hand, we have a “cheatsheet” of some basic axis
Regular
Unity
Cross product
3.- Delta Time #
