python - 事件发生时将矩阵中的元素从 0 更改为 1

Question

我最近用列表编写了一个程序，但现在我需要将列表更改为矩阵。我通过绘制矩形来编写网格。现在我想在单击时更改矩形的颜色。在我的列表程序中，一切正常，但现在我必须使用矩阵，因为我的程序的其余部分需要一个矩阵。我已经有了一个全为零的矩阵，但现在我想在单击矩形时将 0 更改为 1。

x = 5
y = 5

height = 30
width = 50
size = 20
color = (255,255,255)
new_color = (0,255,0)

screen.fill((0,0,0))

def draw_grid():
    for y in range(height):
        for x in range(width):
            rect = pygame.Rect(x * (size + 1),y * (size + 1),size,size)
            pygame.draw.rect(screen,color,rect)
            x += 20
        y += 20

rects = [[0 for i in range(width)] for j in range(height)]
draw_grid()


while 1:
    clock.tick(30)
    for event in pygame.event.get():
        if event.type == QUIT:
            sys.exit()


    if menu == 'start':   

        if pygame.mouse.get_pressed()[0]:
            mouse_pos = pygame.mouse.get_pos()
            for i,(rect,color) in enumerate(rects):
                if rect.collidepoint(mouse_pos):
                    rects[i] = (rect,new_color)

        for rect,color in rects:
            pygame.draw.rect(screen,color,rect)

        pygame.display.flip()

这是我对列表使用的代码，但我已经用矩阵替换了列表。当我运行这段代码时，它给出了一个错误:

ValueError: too many values to unpack

解决这个问题的最佳方法是什么？

Answer 1

要绘制矩形，您可以遍历矩阵并根据值(0 或 1)绘制白色矩形或绿色矩形。 (您也可以将颜色直接存储在矩阵中，但我不知道您是否想用它做其他事情。)

要更改单击的单元格的颜色，您可以通过将鼠标坐标除以 (size+1) 来轻松计算单元格的索引，例如x = mouse_x//(size+1)。然后只需设置 matrix[y][x] = 1。

import sys
import pygame


WHITE = pygame.Color('white')
GREEN = pygame.Color('green')


def draw_grid(screen, matrix, size):
    """Draw rectangles onto the screen to create a grid."""
    # Iterate over the matrix. First rows then columns.
    for y, row in enumerate(matrix):
        for x, color in enumerate(row):
            rect = pygame.Rect(x*(size+1), y*(size+1), size, size)
            # If the color is white ...
            if color == 0:
                pygame.draw.rect(screen, WHITE, rect)
            # If the color is green ...
            elif color == 1:
                pygame.draw.rect(screen, GREEN, rect)


def main():
    screen = pygame.display.set_mode((800, 600))
    clock = pygame.time.Clock()

    height = 30
    width = 50
    size = 20  # Cell size.
    matrix = [[0 for i in range(width)] for j in range(height)]

    done = False

    while not done:
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                done = True

        if pygame.mouse.get_pressed()[0]:
            # To change the color, calculate the indexes
            # of the clicked cell like so:
            mouse_x, mouse_y = pygame.mouse.get_pos()
            x = mouse_x // (size+1)
            y = mouse_y // (size+1)
            matrix[y][x] = 1

        screen.fill((30, 30, 30))
        # Now draw the grid. Pass all needed values to the function.
        draw_grid(screen, matrix, size)

        pygame.display.flip()
        clock.tick(30)


if __name__ == '__main__':
    pygame.init()
    main()
    pygame.quit()
    sys.exit()