Develop Reference

Pygame doesn't draw line

import pygame
import sys
pygame.init()
width, height = 1000, 800
win = pygame.display.set_mode((width, height))
pygame.display.set_caption("Colonizer")
win.fill("white")
pygame.display.update()
def draw():
pygame.draw.line(win, ("black"), [width,height/2], [width*2,height/2], 5)
while True:
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
sys.exit()
draw()
pygame.display.update()
I'm trying to make one simple line and for some reason pygame won't draw it, it just shows white screen.

You cannot "see" the line because it is outside the window. The line starts to the right of the window and continues even further out to the right. Change the coordinates. e.g.:
pygame.draw.line(win, ("black"), [width,height/2], [width*2,height/2], 5)
pygame.draw.line(win, ("black"), [0, height//2], [width, height//2], 5)

How can i give my image an initial position before it starts moving with the mouse?

I'm working on this pygame game and i'm just getting started but got a bit confused because i want the image to move in the x-axis along with the mouse but when i run the program i want the image to show up at the center or the 'floor' but appears at the left side instead. This is my code and a screenshot of what's happening.
import pygame
import sys
pygame.init()
pygame.mixer.init()
WIDTH, HEIGHT = 400, 500
FPS = 60
TITLE = 'FOOD DROP'
SIZE = 190
# Colors
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
BLUE_SKY = (152, 166, 255)
# Display
SCREEN = pygame.display.set_mode((WIDTH, HEIGHT))
pygame.display.set_caption(TITLE)
# Surfaces
floor_surface = pygame.Surface((WIDTH, 100))
floor_surface.fill(BLUE_SKY)
floor_rect = floor_surface.get_rect(midbottom=(200, 500))
# Images
LOAD_DITTO = pygame.image.load('Graphics/ditto.png')
DITTO = pygame.transform.scale(LOAD_DITTO, (SIZE, SIZE))
# Time
CLOCK = pygame.time.Clock()
class Figure:
def draw_figure(self, mouse_x):
SCREEN.blit(DITTO, (mouse_x - 90, 330))
# Game loop
SCREEN_UPDATE = pygame.USEREVENT
# main_game = Main()
figure = Figure()
running = True
while running:
CLOCK.tick(FPS)
mx, my = pygame.mouse.get_pos()
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
sys.exit()
SCREEN.fill(WHITE)
SCREEN.blit(floor_surface, floor_rect)
figure.draw_figure(mx)
pygame.display.update()
When i run the program, this happens:
And i want the image to appear right at the center or the x-axis, not the border, i don't know why is this happening. Just to state, that screenshot was taken when the mouse hadn't been placed over the display.

If the mouse pointer is not in the window (out of focus), the initial position of the mouse pointer is (0, 0). Therefore pygame.mouse.get_pos returns (0, 0). It is also not possible to set the mouse position with pygame.mouse.set_pos if it is not in the window.
Initialize the variables mx and mx with the center of the window. Change the mouse position only when the mouse pointer is in the window (in focus). pygame.mouse.get_focused can be used to test whether the mouse is in the window.
mx, my = SCREEN.get_rect().center
running = True
while running:
CLOCK.tick(FPS)
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
if pygame.mouse.get_focused():
mx, my = pygame.mouse.get_pos()
SCREEN.fill(WHITE)
SCREEN.blit(floor_surface, floor_rect)
figure.draw_figure(mx)
pygame.display.update()
pygame.quit()
sys.exit()

It wont draw my rectangle (pygame on prdroid)

The screen wont fill and it says there is no fill cmd for screen, what did I do wrong?
import pygame
pygame.init()
screen = pygame.display
set_mode((0, 0))
white = (255, 255, 255)
Square =(0, 0, 0)
loop = True
while loop:
screen.fill(white)
pygame.draw.rect(screen, Square, pygame)Rect(100, 100, 200, 200)
pygame.display.update()

There are some syntax errors in your code:
screen = pygame.display
set_mode((0, 0))
screen = pygame.display.set_mode((0, 0))
pygame.draw.rect(screen, Square, pygame)Rect(100, 100, 200, 200)
pygame.draw.rect(screen, Square, pygame.Rect(100, 100, 200, 200))
More than that, the event loop is missing. This can cause your application to freeze. See pygame.event.get() respectively pygame.event.pump():
For each frame of your game, you will need to make some sort of call to the event queue. This ensures your program can internally interact with the rest of the operating system.
Correct program:
import pygame
pygame.init()
screen = pygame.display.set_mode((640, 480))
white = (255, 255, 255)
Square = (0, 0, 0)
loop = True
while loop:
for event in pygame.event.get():
if event.type == pygame.QUIT:
loop = False
screen.fill(white)
pygame.draw.rect(screen, Square, pygame.Rect(100, 100, 200, 200))
pygame.display.update()

Fill only one half of a display in Pygame?

I am new to Pygame and I wish to fill only certain parts of my screen, for example the half. Currently I am only able to fill the complete screen. Can someone help?
import pygame
color= (255, 0, 0)
screen = pygame.display.set_mode((740, 780))
screen.fill(color)

The 2nd parameter of .fill() is a rectangle, which defines the area to be filled.
The width and height of a pygame.Surface object can be get by .get_width() respectively .get_height():
e.g.
screen.fill(color, (0, 0, screen.get_width()// 2, screen.get_height()))

import pygame
size = w,h = 300, 400
scr = pygame.display.set_mode((w,h))
pygame.display.set_caption("Hello")
scr.fill((0,255,0), rect=(0,0,w,h/2))
pygame.display.flip()
running = True
while running:
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
running = False

One way to have partial fill may include "drawing" a shape (i.e. rectangle) on half of the screen.
import sys
import pygame
def half_screen():
#Initialize game and create screen object.
pygame.init()
color= (255, 0, 0)
screen = pygame.display.set_mode((200, 400))
#Draw rectangle to fill the left half of the screen.
left_half = pygame.draw.rect(screen, color,(0,0, 100, 400))
#Start loop for game- keeps screen open until you decide to quit.
while True:
for event in pygame.event.get():
if event.type == pygame.QUIT:
sys.exit()
#Make the current screen visible.
pygame.display.flip()
half_screen()
You can find more information on the draw module - pygame.draw - by going to https://www.pygame.org/docs/ref/draw.html

Python 3.4 Pygame My sprite does not appear

I have written simple code to get a green block which is my sprite to scroll across the screen. When the game starts the sprite is meant to appear in the centre of the screen, however when I run my code the screen is just black and the green block does not appear unless I click on the x cross on the window to exit the screen, then it appears for a second when the window is closing. Any ideas how I can resolve this.
import pygame, random
WIDTH = 800 #Size of window
HEIGHT = 600 #size of window
FPS = 30
WHITE = (255, 255, 255)
BLACK = (0, 0, 0)
RED = (255, 0, 0)
GREEN = (0, 255, 0)
BLUE = (0, 0, 255)
class Player(pygame.sprite.Sprite):
#sprite for the player
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.Surface((50, 50))
self.image.fill(GREEN)
self.rect = self.image.get_rect()
self.rect.center = (WIDTH/2, HEIGHT/2)
def update(self):
self.rect.x += 5
#initialize pygame and create window
pygame.init()
pygame.mixer.init()
screen = pygame.display.set_mode((WIDTH, HEIGHT))
pygame.display.set_caption("My Game")
clock = pygame.time.Clock()
all_sprites = pygame.sprite.Group()
player = Player()
all_sprites.add(player)
#Game loop
running = True
while running:
clock.tick(FPS)
for event in pygame.event.get():
#check for closing window
if event.type == pygame.QUIT:
running = False
#update
all_sprites.update()
#Render/Draw
screen.fill(BLACK)
all_sprites.draw(screen)
pygame.display.flip()
pygame.quit()

All your code to updat the sprites, fill the screens and draw the sprites is outside your main loop (while running)
You must have in mind that identation Python's syntax: your commands are just outside your mainloop.
Moreover, I'd strongly advise to put that mainloop inside a proper function, instead of just leaving it on the module root.
...
#Game loop
running = True
while running:
clock.tick(FPS)
for event in pygame.event.get():
#check for closing window
if event.type == pygame.QUIT:
running = False
#update
all_sprites.update()
#Render/Draw
screen.fill(BLACK)
all_sprites.draw(screen)
pygame.display.flip()
pygame.quit()