[turtle]How would I create gravity?

[turtle]How would I create gravity? - Printable Version

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[turtle]How would I create gravity? - GalaxyCoyote - May-19-2019

I want to make a simple platforming game where the player must reach the end, but at the moment I just have 2-way movement (right and left) is there any way I could simulate gravity?

Some notes: I am not using pygame.

Edit: here is the code I have,

import turtle
import time
pause = 0.1
#screen
Screen = turtle.Screen()
Screen.title("Block")
Screen.bgcolor("white")
Screen.setup(width=1280, height=720)
Screen.tracer(0)#turns off the screen updates

#game
Block = turtle.Turtle()
Block.speed(0)#no slow down with animation speed
Block.shape("square")#shape
Block.color("black")#color not colour
Block.penup()#stops drawing
Block.goto(0,0)#spawns in
Block.direction = "stop"#cant you read
    

#fucntions
def go_up():
    Block.direction = "up"

def go_down():
    Block.direction = "down"

def go_left():
    Block.direction = "left"

def go_right():
    Block.direction = "right"
    
def move():
    if Block.direction == "up":
        y = Block.ycor()
        Block.sety(y + 20)
        
        #time.sleep()
    
    elif Block.direction == "down":
        y = Block.ycor()
        Block.sety(y - 20)

    elif Block.direction == "left":
        x = Block.xcor()
        Block.setx(x - 20)

    elif Block.direction == "right":
        x = Block.xcor()
        Block.setx(x + 20)

#keyboard

Screen.onkeypress(go_up, "w")
Screen.onkeypress(go_down, "`")
Screen.onkeypress(go_left, "a")
Screen.onkeypress(go_right, "d")
Screen.listen()

#gameloop
while True:
    Screen.update()
    
    move()
    
    time.sleep(pause)
        
Screen.mainloop()

RE: How would I create gravity? - ichabod801 - May-19-2019

Just drop the piece a little every turn. You could just put this at the end of the move function:

y = Block.ycor()
Block.sety(y - 10)

Of course, gravity is an acceleration, not just a speed. you could have a variable gravity that starts at -10, decreases by 10 every turn, but increases by 20 (to a max of -10) if you go up. Since you are not using OOP, I would say make that a variable in your while True loop, pass it to move as a parameter, and return the updated value back to the while loop.

RE: [turtle]How would I create gravity? - gr3tnosk - May-29-2019

hm, seems you should add gravity, but just as ichabod801 said, it will need to accelerate, but at the same time not let the turtle escape the screen. I haven't worked with pygame, but I've seen a similar problem and solution on stackoverflow: https://stackoverflow.com/questions/16551009/gravity-in-pygame

according to this, you would have to determine your initial gravity and just add to it.

RE: [turtle]How would I create gravity? - TTChaos - May-29-2019

Do something like:

speed_y = 0
while True:
    speed_y -= 1
    y = block.ycor()
    Block.sety(y+speed_y)

Though this would create a problem making the player fall through the floor.
Assuming you have a square for a floor(with size 15) right underneath the block:

def touch_ground():
    while turtle.distance(square) < 15:
        Block.sety(y+1)
        speed_y = 0

while True:
    speed_y -= 1
    y = Block.ycor()
    Block.sety(y+speed_y)
    touch_ground()

RE: [turtle]How would I create gravity? - joe_momma - May-31-2019

Long time ago they had a demo of the earth and moon rotating the sun. it can be found here:
https://svn.python.org/projects/python/trunk/Demo/turtle/tdemo_planet_and_moon.py