Application pauses when dragging window

SDL Development
1

This is on Win32. I have read a few places on the web of others having the same
problem but no solutions have been posted yet. Is there a way to move a window
without the application pausing on Windows?

2

This is on Win32. I have read a few places on the web of others having the same
problem but no solutions have been posted yet. Is there a way to move a window
without the application pausing on Windows?

Not as far as I know… If anyone knows how to do this, please let me know.

See ya,
-Sam Lantinga, Software Engineer, Blizzard Entertainment

3

It’s a bug (or feature? sure looks lika a bug to me…) in Windows
that hijacks the message loop when the user grabs the title bar. Two
ways around it (there may be others):

  • Do all rendering in another thread than the one that
    does the message handling. The window related message
    handling is still hijacked, but rendering and stuff
    can keep going.

  • Use a borderless window and render your own frame. Of
    course, this can potentially give you one of those evil,
    annoying WinAmp style things that appear to violate all
    UI guidelines and platform conventions just for the h*ll
    of it, but it does have the advantage that you do all
    dragging and stuff yourself, so you avoid the title bar
    hijack bug/feature.

//David Olofson - Programmer, Composer, Open Source Advocate

.- Audiality -----------------------------------------------.
| Free/Open Source audio engine for games and multimedia. |
| MIDI, modular synthesis, real time effects, scripting,… |
`-----------------------------------> http://audiality.org -’
— http://olofson.net — http://www.reologica.se —On Friday 12 November 2004 22.50, Sam Lantinga wrote:

This is on Win32. I have read a few places on the web of others
having the same problem but no solutions have been posted yet. Is
there a way to move a window without the application pausing on
Windows?

Not as far as I know… If anyone knows how to do this, please let
me know.

4

This is on Win32. I have read a few places on the web of others
having the same problem but no solutions have been posted yet.
Is there a way to move a window without the application pausing
on Windows?

Not as far as I know… If anyone knows how to do this, please
let me know.

It’s a bug (or feature? sure looks lika a bug to me…) in Windows
that hijacks the message loop when the user grabs the title bar.
Two ways around it (there may be others):

  • Do all rendering in another thread than the one that
    does the message handling. The window related message
    handling is still hijacked, but rendering and stuff
    can keep going.

Clarification: I’m talking about the Win32 message loop here. You’ll
probably have to hack SDL’s Win32 code to do this.

  • Use a borderless window and render your own frame. Of
    course, this can potentially give you one of those evil,
    annoying WinAmp style things that appear to violate all
    UI guidelines and platform conventions just for the h*ll
    of it, but it does have the advantage that you do all
    dragging and stuff yourself, so you avoid the title bar
    hijack bug/feature.

…and for this, you might have to do some platform specific event
handling and stuff to implement dragging, resizing etc.

//David Olofson - Programmer, Composer, Open Source Advocate

.- Audiality -----------------------------------------------.
| Free/Open Source audio engine for games and multimedia. |
| MIDI, modular synthesis, real time effects, scripting,… |
`-----------------------------------> http://audiality.org -’
— http://olofson.net — http://www.reologica.se —On Sunday 14 November 2004 15.55, David Olofson wrote:

On Friday 12 November 2004 22.50, Sam Lantinga wrote: