python - Pygame - 位图预览图片

首先，这是一项学校作业，所以我想提前说明这一点。其次，我只是寻求有关方法的建议，可能对代码有帮助。我正在使用我们书中的一些预先存在的代码来处理 MSPAINT 风格的克隆。代码中已经有了按下鼠标按钮1时的draw.line的使用。老师要我们添加制作圆形或矩形的能力。我正在研究圆部分，我已经想出了(感谢这里的论坛)如何实现我想要用 MOUSEBUTTONDOWN 和 MOUSEBUTTONUP 事件做的事情..这让我想到了一个新问题..我该怎么做blit 然后删除然后 blit 一个圆圈的预览，直到它是用户想要的大小，然后他们释放鼠标按钮并查看最终的 blit ...

while keepGoing:
    clock.tick(30)

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            keepGoing = False
        elif event.type == pygame.MOUSEMOTION:
            lineEnd = pygame.mouse.get_pos()
            if pygame.mouse.get_pressed() == (1,0,0):
                pygame.draw.line(background, drawColor, lineStart, lineEnd, lineWidth)
            lineStart = lineEnd
        elif event.type == pygame.MOUSEBUTTONDOWN and event.button == 3:
                    circleStart = pygame.mouse.get_pos()
        elif event.type == pygame.MOUSEBUTTONUP and event.button == 3:
                    circleEnd = pygame.mouse.get_pos()
                    size = (circleEnd[0] - circleStart[0])
                    pygame.draw.circle(background, drawColor, circleStart, size, lineWidth)
        elif event.type == pygame.KEYDOWN:
            myData = (event, background, drawColor, lineWidth, keepGoing)
            myData = checkKeys(myData)
            event, background, drawColor, lineWidth, keepGoing) = myData

非常感谢

-本

最佳答案

因此，经过一番思考，这是我想出的使用 pygame 的最佳解决方案。告诉我你的想法以及它是否对你有帮助。

import pygame,sys,math #---- Import modules we will need

pygame.init() #---- Initialize the module

def get_rad(origin_x,origin_y,x,y): #----- Returns the appropriate radius
    return math.sqrt((origin_x - x)**2 + (origin_y - y)**2) #----- Distance between 2
                                                            #----- points

screen = pygame.display.set_mode((400,400)) #----- Sets up the screen
clock  = pygame.time.Clock() #------- Sets up the clock

mouse_button = 0 #--------- This variable is used to determine whether a mouse button
                 #--------- has been pressed

draw_final_circle = False #---------- This variable lets us know that we should draw the
                          #---------- final circle

while True: #------ main loop

    clock.tick(60) #------ Limit the Fps

    mouse_button0  = mouse_button #-------- This variable holds the previous value of
                                  #-------- mouse_button(it will be useful later)

    mouse_x,mouse_y = pygame.mouse.get_pos() #----- Get the mosue coordinates

    for e in pygame.event.get(): #---- Cycle through events

        if e.type == pygame.QUIT: pygame.quit();sys.exit() #--Quit when window is closed

        if e.type == pygame.MOUSEBUTTONDOWN: #---- If the mouse button is pressed
            if mouse_button == 0: #---- if the mouse button is released
                mouse_button = 1 #----- set it to pressed basically
                originx,originy = mouse_x,mouse_y #---- keep the mouse_x,mouse_y pos

        if e.type == pygame.MOUSEBUTTONUP: #---- if the mouse button is released
             if mouse_button == 1: #-------- if it is pressed
                 mouse_button = 0 #--------- set it to released

    screen.fill((255,255,255)) #---- clear the screen


    #-------- If a mouse button is pressed and a circle can be drawn (rad>width) ------#
    if mouse_button == 1 and get_rad(originx,originy,mouse_x,mouse_y) > 1:

        rad = int(get_rad(originx,originy,mouse_x,mouse_y)) #---- get the radius(as int)
        pos = mouse_x,mouse_y
        pygame.draw.circle(screen,(0,0,0),pos,rad,1) #--- draw the circle

    #----------------------------------------------------------------------------------#


    #---------- if the button is released but in the previous loop it was pressed -----#
    if mouse_button == 0 and mouse_button0 == 1:

        draw_final_circle = True #----- set the final circle boolean to True

    if draw_final_circle: #----- if the final circle is decided
        pygame.draw.circle(screen,(0,0,0),pos,rad,1) #---- keep drawing it

    pygame.display.flip() #----- flip the buffer

关于python - Pygame - 位图预览图片，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/22403203/