python - Scale Everything On Pygame Display Surface

Question

So I'm making a 2D pixel art game in pygame and as you could assume, all my sprite textures appear very small. I'm wondering if there's a way I can globally scale everything up in my game without either having to scale each sprite up individually or messing up the coordinates. Every sprite will move on a grid: one unit is 16x16 pixels and when my player sprite moves, for example, it will just move over in a direction 16 pixels.

Here's my main script:

import sys
from pygame.locals import *
import pygame

from game.sprites import Ghost

pygame.init()

WINDOW_WIDTH = 640
WINDOW_HEIGHT = 640
DES_WIDTH = 64
DES_HEIGHT = 64

COL_BG = (46, 48, 55)
COL_FG = (235, 229, 206)

X = 1000
Y = 1000

win = pygame.display.set_mode((WINDOW_WIDTH, WINDOW_HEIGHT))
pygame.display.set_caption("Through The Doors")

running = True
paused = False

# INITIALIZE SPRITES
player = Ghost()

all_sprites = pygame.sprite.Group()
all_sprites.add(player)

clock = pygame.time.Clock()

while running:
    clock.tick(30)

    if not paused:
        win.fill(COL_BG)
        all_sprites.update()
        all_sprites.draw(win)

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()

    keys = pygame.key.get_pressed()

    if keys[pygame.K_RIGHT]:
        player.go_right()
    elif keys[pygame.K_LEFT]:
        player.go_left()
    elif keys[pygame.K_UP]:
        player.go_up()
    elif keys[pygame.K_DOWN]:
        player.go_down()

    pygame.display.flip()

pygame.quit()

I do have more sprites I am going to load in, but I would like to resolve the scaling issue first.

" I'm wondering if there's a way I can globally scale everything up in my game without either having to scale each sprite up individually [...]" - No there is no way. You have to scale each coordinate, each size and each surface individually. PyGame is made for images (Surfaces) and shapes in pixel units. Anyway up scaling an image causes either a blurred or jagged (minecraft) look. — Rabbid76
Please repeat on topic and how to ask from the intro tour. “Show me how to solve this coding problem” is not a Stack Overflow issue. We expect you to make an honest attempt, and then ask a specific question about your algorithm or technique. Posting your entire program for a question of perhaps 20 lines is ... not proper format. — Prune
Is there a way I could make a seperate surface and just put that on top of the base window surface, and just scale that? If yes can you show me how? — yonderbread

Rabbid76 Rabbid76 · Accepted Answer · 2020-10-13T19:16:23

I'm wondering if there's a way I can globally scale everything up in my game without either having to scale each sprite up individually [...]"

No there is no way. You have to scale each coordinate, each size and each surface individually. PyGame is made for images (Surfaces) and shapes in pixel units. Anyway up scaling an image will result in either a fuzzy, blurred or jagged (Minecraft) appearance.

Is there a way I could make a separate surface and just put that on top of the base window surface, and just scale that?

Yes of course.

Create a Surface to draw on (win). Use pygame.transform.scale() or pygame.transform.smoothscale() to scale it to the size of the window and blit it to the actual display Surface (display_win):

display_win = pygame.display.set_mode((WINDOW_WIDTH*2, WINDOW_HEIGHT*2))
win = pygame.Surface((WINDOW_WIDTH, WINDOW_HEIGHT))

while running:
    # [...]

    if not paused:
        win.fill(COL_BG)
        all_sprites.update()
        all_sprites.draw(win)

    # [...]

    scaled_win = pygame.transform.smoothscale(win, display_win.get_size())
    # or scaled_win = pygame.transform.scale(win, display_win.get_size())
    display_win.blit(scaled_win, (0, 0))
    pygame.display.flip()

Minimal example: repl.it/@Rabbid76/PyGame-UpScaleDisplay

python - Scale Everything On Pygame Display Surface

1 Answers