Re: [pygame] Drawing a box with the mouse

[Ethan Glasser-Camp <glasse@xxxxxxxxxx>]

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Eric Hunter wrote:
>         if event.type == pygame.MOUSEBUTTONDOWN:
>             mouseX1, mouseY1 = pygame.mouse.get_pos ()
>             print "Mouse 1", mouseX1, mouseY1
>             clear = pygame.event.clear()
>             while not pygame.MOUSEBUTTONDOWN:
>                 mouseX2, mouseY2 = pygame.mouse.get_pos()
>                 print "Mouse 2", mouseX2, mouseY2
>                 box_resize = ((mouseX2 - mouseX1) + 1), ((mouseY2 -
> mouseY1) + 1)
>                 yellow_block = pygame.transform.scale(yellow_block,
> box_resize)
>                 background.blit(yellow_block, (mouseX1, mouseY1))
>                 screen.blit(background, (0, 0))
>                 pygame.display.update(yellow_block)

In case it wasn't clear, Ian's opinion is that it is easier to rewrite
 this script than fix it. The problem is that your while loop, "while
not pygame.MOUSEBUTTONDOWN" doesn't do what you want it to do -- check
events until one of them is pygame.MOUSEBUTTONDOWN. Instead it
computes the value of "not pygame.MOUSEBUTTONDOWN"
(pygame.MOUSEBUTTONDOWN happens to be 5, so the "not" of that is
False) and breaks out immediately. Even if you wrote your while loop
to actually check events (and keep checking them), it wouldn't be a
good idea, because your "main loop" probably does other things that
you don't want your little while loop to duplicate. (For example,
checking for pygame.QUIT.) Instead, you should structure your main
loop to check for clicks and act accordingly, like Ian did.

Hope this helps!

Ethan
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