[bb] Coordinated Flip by jfk EO-11110 [ 1+ years ago ]

[BlitzBot]

Title : Coordinated Flip
Author : jfk EO-11110
Posted : 1+ years ago

Description : ;This is about how to make sure Windows Messages won't be
;drawn to the backbuffer in fullscreen mode.

Code :

Code (blitzbasic) Select Expand

;Sometimes Windows Api Messages such as System Alerts or
;Firewall Queries remain invisible because they are drawn to
;the backbuffer and pause the Blitz App in Fullscreen Mode.

;This is about how to make sure Windows Messages won't be
;disguised in the backbuffer in fullscreen mode.

;Why are the messages not drawn everytime to the front  
;buffer or to the backbuffer, why is it some kind of random
;game with them?

;The reason why is there are two buffers, lets name them
;Buffer 1 and Buffer 2. They always remain Buffer 1 and 2,
;no matter if we made them Frontbuffer or Backbuffer! And
;windows (as usual) doesn't know about frontbuffer or
;backbuffer and simply writes to Buffer 1 all the time.

;So all we have to do is watch every flip closely and use a
;counter that will tell us if we are watching Buffer 1 or 2.

;This is pretty easy, simply replace your current Flip
;commands with a function call. EG:

global flipcounter
...

CoFlip() ; replaces a normal Flip

...

function CoFlip(waitsync=1)
 flip waitsync
 flipcounter=flipcounter xor 1
end function

;now right before we call a function or external Exe that will
;force some Win Api High priority Alert (like when you
;connect to the internet and eg. a Firewall like Zonealarm
;throws a prompt to the user), to make sure your game won't
;freeze with an alert in the backbuffer that waits for user
;action, all you have to do is this:

if flipcounter=1 then CoFlip(0)

;of course, you may also add an additional Renderworld
;before to make sure everything looks nice.

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