Pygame报错：argument 1 must be pygame.Surface, not pygame.Rect 如何解决？铅笔点击类游戏开发问题排查

Hey there! Let's break down why your Pygame window isn't showing content and fix that error once and for all.

The Root Cause #

That error message tells you exactly what's wrong: TypeError: argument 1 must be pygame.Surface, not pygame.Rect. Here's the breakdown:

• When you use font.render(), it creates a Surface—this is the actual text image you want to draw on the screen.
• The screen.blit() method needs two arguments: first the Surface to render, then the position (either a coordinate tuple or a Rect object).
• You accidentally swapped these: you passed the Rect (from PENCILS.get_rect()) as the first argument instead of the Surface itself. That's why Pygame throws the type error.

Step-by-Step Fixes #

Let's correct your code and fix a couple of small logic issues too:

1. Fix the screen.blit() call order
   Pass the Surface first, then use the Rect to define where it should be drawn.

2. Fix the "Per Second" text display
   You're currently rendering user.pencils for both lines—you meant to use user.pencilspersecond for the second line to show the passive gain.

3. Fix the click increment logic
   Your click handler uses user.score +=1, but your Player class only has a pencils attribute. Change that to user.pencils +=1 to actually increase your pencil count.

4. Add screen clearing and display updates
   Without clearing the screen each frame, old content will stick around, and without updating the display, nothing will show up even after fixing the blit error.

Corrected Code Snippet #

Here's the updated version of your relevant code with all fixes applied:

class pencilsDisplay():
    def __init__(self, x, y):
        self.x = x
        self.y = y
        self.height = 100
        self.length = 100
    def draw(self):
        font = pygame.font.Font('font/Gidole-Regular.ttf', 24)
        # Render text surfaces first
        PENCILS = font.render(f'{int(user.pencils)} Pencils', True, WHITE)
        # Fixed: Use pencilspersecond instead of pencils for the second line
        PENCILSPERSECOND = font.render(f'Per Second: {int(user.pencilspersecond)}', True, WHITE)
        
        # Get rects for positioning, then blit the surfaces in the correct order
        pencil_rect = PENCILS.get_rect(center=(int(self.x + self.length/2), int(self.y + 20)))
        screen.blit(PENCILS, pencil_rect)
        
        # Adjust y-position to prevent overlapping text
        pps_rect = PENCILSPERSECOND.get_rect(center=(int(self.x + self.length/2), int(self.y + 50)))
        screen.blit(PENCILSPERSECOND, pps_rect)

class Player:
    def __init__(self):
        self.pencils = 0
        self.pencilspersecond = 0

user = Player()
pencil = MainPencil(100,100)
pencil_display = pencilsDisplay(100,0)

def draw():
    # Clear the screen with a background color (black here)
    screen.fill((0, 0, 0))
    pencil.draw()
    pencil_display.draw()
    # Update the display to show all drawn elements
    pygame.display.flip()

running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.MOUSEBUTTONDOWN:
            mouse_pos = event.pos
            if pencil.collidepoint(mouse_pos):
                # Fixed: Increment pencils instead of non-existent score
                user.pencils += 1
                pencil.animation_state = 1
        if event.type == pygame.QUIT:
            running = False
    draw()

Quick Tips for Pygame Newbies #

• Always clear the screen with screen.fill() at the start of your draw() function to avoid smearing old frames.
• Call pygame.display.flip() or pygame.display.update() after drawing everything to refresh the window.
• Double-check attribute names (like pencils vs score) to avoid unexpected AttributeErrors later.

内容的提问来源于stack exchange，提问作者Jack Doherty