Pigame: cell physics

I'm doing a lowered version Agar.io .

Currently, the cell is placed against the background of the grid, as in the game. The cell eats food, but only the smaller square portion inside the circle actually eats food (in my program), which is noticeable when you are big enough. Also, when you press the spacebar, it splits the cell into two smaller pieces, which will be merged back in a few seconds. This will require an event KEY_UP

and K_SPACE

, but I'm not sure how to implement this. Also, once you're around 34 mass, you can press w to shoot a tiny chunk, a smaller cell around 14 of the given mass.

I tried to slow down the cell when it reaches a certain mass with a bunch of if statements. It slows down naturally in play. Here and Here are sources depicting the mathematics used in the game,

Here is the code I have:

import pygame, sys, random
from pygame.locals import *

# set up pygame
pygame.init()
mainClock = pygame.time.Clock()

# set up the window
width = 800
height = 600
thesurface = pygame.display.set_mode((width, height), 0, 32)
pygame.display.set_caption('')

bg = pygame.image.load("bg.png")
basicFont = pygame.font.SysFont('calibri', 36)

# set up the colors
BLACK = (0, 0, 0)
GREEN = (0, 255, 0)
WHITE = (255, 255, 255)
BLUE = (0, 0, 255)
size = 10
playercolor = BLUE
# set up the player and food data structure
foodCounter = 0
NEWFOOD = 35
FOODSIZE = 10
player = pygame.draw.circle(thesurface, playercolor, (60, 250), 40)
foods = []
for i in range(20):
    foods.append(pygame.Rect(random.randint(0, width - FOODSIZE), random.randint(0, height - FOODSIZE), FOODSIZE, FOODSIZE))

# set up movement variables
moveLeft = False
moveRight = False
moveUp = False
moveDown = False

MOVESPEED = 10

score = 0
# run the game loop
while True:
    # check for events
    for event in pygame.event.get():
        if event.type == QUIT:
            pygame.quit()
            sys.exit()
        if event.type == KEYDOWN:
            # change the keyboard variables
            if event.key == K_LEFT or event.key == ord('a'):
                moveRight = False
                moveLeft = True
            if event.key == K_RIGHT or event.key == ord('d'):
                moveLeft = False
                moveRight = True
            if event.key == K_UP or event.key == ord('w'):
                moveDown = False
                moveUp = True
            if event.key == K_DOWN or event.key == ord('s'):
                moveUp = False
                moveDown = True
        if event.type == KEYUP:
            if event.key == K_ESCAPE:
                pygame.quit()
                sys.exit()
            if event.key == K_LEFT or event.key == ord('a'):
                moveLeft = False
            if event.key == K_RIGHT or event.key == ord('d'):
                moveRight = False
            if event.key == K_UP or event.key == ord('w'):
                moveUp = False
            if event.key == K_DOWN or event.key == ord('s'):
                moveDown = False
            if event.key == ord('x'):
                player.top = random.randint(0, height - player.height)
                player.left = random.randint(0, width - player.width)

        if event.type == MOUSEBUTTONUP:
            foods.append(pygame.Rect(event.pos[0], event.pos[1], FOODSIZE, FOODSIZE))

    foodCounter += 1
    if foodCounter >= NEWFOOD:
        # add new food
        foodCounter = 0
        foods.append(pygame.Rect(random.randint(0, width - FOODSIZE), random.randint(0, height - FOODSIZE), FOODSIZE, FOODSIZE))
    if 100>score>50:
        MOVESPEED = 9
    elif 150>score>100:
        MOVESPEED = 8
    elif 250>score>150:
        MOVESPEED = 6
    elif 400>score>250:
        MOVESPEED = 5
    elif 600>score>400:
        MOVESPEED = 3
    elif 800>score>600:
        MOVESPEED = 2
    elif score>800:
        MOVESPEED = 1
    # move the player
    if moveDown and player.bottom < height:
        player.top += MOVESPEED
    if moveUp and player.top > 0:
        player.top -= MOVESPEED
    if moveLeft and player.left > 0:
        player.left -= MOVESPEED
    if moveRight and player.right < width:
        player.right += MOVESPEED
    thesurface.blit(bg, (0, 0))

    # draw the player onto the surface
    pygame.draw.circle(thesurface, playercolor, player.center, size)

    # check if the player has intersected with any food squares.
    for food in foods[:]:
        if player.colliderect(food):
            foods.remove(food)
            size+=1
            score+=1

    # draw the food
    for i in range(len(foods)):
        pygame.draw.rect(thesurface, GREEN, foods[i])

    printscore = basicFont.render("Score: %d" % score, True, (0,0,0))
    thesurface.blit(printscore, (495, 10))

    pygame.display.update()
    # draw the window onto the thesurface
    pygame.display.update()
    mainClock.tick(80)

      

        
        
        
      

    

Once again, here are the problems I want to solve.

• I want the cell to be split in 2 when the spacebar is pressed. This can only happen if the cell is over 30.
• I want the cell to spit out a part of itself when you press W. The part to spit out will be 15 masses. The original cell will be less than 15. If you hit W multiple times, you can align several small balls until the original cell mass is 20, in which case it is not safe to spit out.

Edit: I've tried doing the splitting:

if event.key == K_SPACE:
    pygame.draw.circle(thesurface, playercolor,(player.centerx,player.centery),int(size/2))
    pygame.draw.circle(thesurface, playercolor,(player.centerx+size,player.centery+size),int(size/2))

      

        
        
        
      

    

After entering the above code and running the program and pressing the spacebar, nothing happens. The program acts as if I have never pressed it.