Vectors in PyGame

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Python can use tuples and lists to essentially represent a vector, however these will not allow you to do any real vector calculations.

for example:

pos = [200,200]

Pygame has a built in maths module for 2D vector calcuations, you can import it:

import pygame.math as math

You can then create a new vector:

test = math.Vector2(200,200)

You can access the x and y coordinate:

test = math.Vector2(200,200)

Simple Calculations

You can add, subtract, multiply or divide vectors using standard calculations:

PositionA = math.Vector2(200,200)
PositionB = math.Vector2(500,300)
Distance = PositionB - PositionA
Position= math.Vector2(200,200)
Movement = math.Vector2(1,1)
Position += Movement
Position= math.Vector2(200,200)
Movement *= 2

Special Calculations

Dot Product

You can calculate the dot product between the vector and any other vector:



Although pygame.math should contain a magnitude method, however this doesn't seem to be enabled. However the same calculation is also done by the length method:

MAGNITUDE = test.length()


Pygame.math has a built in method to calculate the distance between any two vectors:

DISTANCE = test.distance_to(math.Vector2(10,10))

Bounce / Reflect

Pygame.math does have a reflect and reflect_ip method to use a bounce, however you could easily do this yourself. If it is a horizontal bounce (from left or right) you have to negate the x coordinate:

test = math.Vector2((test.x*-1)  ,test.y)

For a vertical bounce, you need to negate the y coordinate:

test = math.Vector2(test.x , (test.y*-1))

Other Features

Pygame.math has other features and methods to use, check them out: