Pygame(五)畫線

前情提要

作業代碼

import sys
import pygame
from math import pi

def homework():
    pygame.init()
    screen = pygame.display.set_mode((800, 600))
    screen.fill((255, 255, 255))

    # 畫正方形
    rect = (300,200,200,200)
    pygame.draw.rect(screen, (0,0,255), rect,5)

    # 畫上側的弧
    rect = (300, 100, 200, 200)
    pygame.draw.arc(screen, (0,255,0), rect, pi, 2*pi, width=5)

    # 畫下側的弧
    rect = (300, 300, 200, 200)
    pygame.draw.arc(screen, (0, 255, 0), rect, 0, pi, width=5)

    # 畫左側的弧
    rect = (200, 200, 200, 200)
    pygame.draw.arc(screen, (0, 255, 0), rect, - pi/2, pi/2, width=5)
    # 畫右側弧
    rect = (400, 200, 200, 200)
    pygame.draw.arc(screen, (0, 255, 0), rect, pi / 2, -pi / 2, width=5)

    pygame.display.update()

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

    pygame.quit()


if __name__ == '__main__':
    homework()

內容提要

內容詳解

畫線段

pygame.draw.line(Surface, color, startpos, endpos, width)

引數決議

• Surface: Surface物件
• color: 線段顏色
• startpos: 線段的起點坐標, 一個二元組(x,y)
• endpos: 線段的終點坐標, 一個二元組(x,y)
• width: 線條的寬度,默認值為1

示例程式

def draw_line():
    pygame.init()
    screen = pygame.display.set_mode((800, 600))
    screen.fill((255, 255, 255))

    start_pos = 400, 300  # 起點
    end_pos = 400, 200  # 終點
    RED = (255, 0, 0)  # 定義紅色
    pygame.draw.line(screen, RED, start_pos, end_pos, 20)  # 畫線段

    pygame.display.update()

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

    pygame.quit()

示例圖形:

畫折線(多條連續的線段)

pygame.draw.lines(Surface, color, closed, pointlist, width)

引數決議

• Surface: Surface物件
• color: 線條顏色
• closed: 是否封閉圖形,布爾型.True:起點與終點會連起來成為一個封閉圖形 ,False:起點與終點不會連起來
• pointlist: 折線各個節點的坐標串列. 元素是二元組的串列
• width: 線寬.默認值為1

示例程式

def draw_lines():
    pygame.init()
    screen = pygame.display.set_mode((800, 600))
    screen.fill((255, 255, 255))

    p_list = [(400, 300), (400, 200), (500, 200), (500, 400)]  # 定義各個折點的坐標
    RED = (255, 0, 0)  # 定義紅色
    pygame.draw.lines(screen, RED, True, p_list, 1)  # 畫封閉的圖
    pygame.display.update()  # 更新螢屏

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

示例圖形

畫反鋸齒線段,折線段與多邊形

pygame.draw.aaline(Surface, color, startpos, endpos, width)
pygame.draw.aalines(Surface, color, closed, pointlist, width)
pygame.draw.polygon(Surface, color, pointlist, width)

這邊就不詳細解釋.用法了,除了函式名多了兩個a之外用法與畫線段與畫折線段一樣.

綜合示例

示例代碼

def draw_balance():
    pygame.init()
    screen = pygame.display.set_mode((800, 600))
    screen.fill((255, 255, 255))

    RED = (255, 0, 0)  # 定義紅色

    # 底座三角形三個點
    triangle_list = [(400, 300), (350, 350), (450, 350)]
    pygame.draw.polygon(screen, RED, triangle_list)


    # 秤桿
    start_pos = 150, 275
    end_pos = 700, 325
    # pygame.draw.line(screen, RED, start_pos, end_pos, 3)
    pygame.draw.aaline(screen, RED, start_pos, end_pos, 3)

    # 畫重物
    # 左邊放一個正方形,右邊放一個圓, 因為秤桿是斜的,所以正方形不能直接用rect來畫.選擇用多邊形來畫

    # 定義藍色
    BLUE = (0, 0, 255)
    rect_list = [(150, 275),(200, 280),(208,230), (158, 225)]
    pygame.draw.polygon(screen, BLUE, rect_list)

    circle_center = 680, 300
    r = 22
    pygame.draw.circle(screen, BLUE, circle_center, r)

    pygame.display.update()  # 更新螢屏
    while 1:
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                sys.exit()
    pygame.quit()

效果圖

練習:

嘗試畫出如下組合圖形