Vectors in PyGame
Contents
Intro
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)
print(test.x)
print(test.y)
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:
test=math.Vector2(200,200)
DOTPRODUCT = test.dot(math.Vector2(10,10))
Magnitude
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:
test=math.Vector2(200,200)
MAGNITUDE = test.length()
Distance
Pygame.math has a built in method to calculate the distance between any two vectors:
test=math.Vector2(200,200)
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:
