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Fixed bug #55 From Christian Walther: When writing my patch for #12, I ended up doing all sorts of changes to the way application/window activating/deactivating is handled in the Quartz backend, resulting in the attached patch. It does make the code a bit cleaner IMHO, but as it might be regarded as a case of "if it ain't broken, don't fix it" I'd like to hear other people's opinion about it. Please shout if some change strikes you as unnecessary or wrong, and I'll explain the reasons behind it. As far as I tested it, it does not introduce any new bugs, but I may well have missed some. - The most fundamental change (that triggered most of the others) is irrelevant for the usual single-window SDL applications, it only affects the people who are crazy enough to display other Cocoa windows alongside the SDL window (I'm actually doing this currently, although the additional window only displays debugging info and won't be present in the final product): Before, some things were done on the application becoming active, some on the window becoming key, and some on the window becoming main. Conceptually, all these actions belong to the window becoming key, so that's what I implemented. However, since in a single-window application these three events always happen together, the previous implementation "ain't broken". - This slightly changed the meaning of the SDL_APPMOUSEFOCUS flag from SDL_GetAppState(): Before, it meant "window is main and mouse is inside window (or mode is fullscreen)". Now, it means "window is key and mouse is inside window (or mode is fullscreen)". It makes more sense to me that way. (See http://developer.apple.com/documentation/Cocoa/Conceptual/WinPanel/Concepts/ChangingMainKeyWindow.html for a discussion of what key and main windows are.) The other two flags are unchanged: SDL_APPACTIVE = application is not hidden and window is not minimized, SDL_APPINPUTFOCUS = window is key (or mode is fullscreen). - As a side effect, the reorganization fixes the following two issues (and maybe others) (but they could also be fixed in less invasive ways): * A regression that was introduced in revision 1.42 of SDL_QuartzVideo.m (http://libsdl.org/cgi/cvsweb.cgi/SDL12/src/video/quartz/SDL_QuartzVideo.m.diff?r1=1.41&r2=1.42) (from half-desirable to undesirable behavior): Situation: While in windowed mode, hide the cursor using SDL_ShowCursor(SDL_DISABLE), move the mouse outside of the window so that the cursor becomes visible again, and SDL_SetVideoMode() to a fullscreen mode. What happened before revision 1.42: The cursor is visible, but becomes invisible as soon as the mouse is moved (half-desirable). What happens in revision 1.42 and after (including current CVS): The cursor is visible and stays visible (undesirable). What happens after my patch: The cursor is invisible from the beginning (desirable). * When the cursor is hidden and grabbed, switch away from the application using cmd-tab (which ungrabs and makes the cursor visible), move the cursor outside of the SDL window, then cmd-tab back to the application. In 1.2.8 and in the current CVS, the cursor is re-grabbed, but it stays visible (immovable in the middle of the window). With my patch, the cursor is correctly re-grabbed and hidden. (For some reason, it still doesn't work correctly if you switch back to the application using the dock instead of cmd-tab. I haven't been able to figure out why. I can step over [NSCursor hide] being called in the debugger, but it seems to have no effect.) - The patch includes my patch for #12 (it was easier to obtain using cvs diff that way). If you apply both of them, you will end up with 6 duplicate lines in SDL_QuartzEvents.m.
author Sam Lantinga <slouken@libsdl.org>
date Thu, 13 Apr 2006 14:17:48 +0000
parents 355632dca928
children 85cbe9c892f4
line wrap: on
line source

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>SDL_Event</H1
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><H2
>Name</H2
>SDL_Event&nbsp;--&nbsp;General event structure</DIV
><DIV
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><A
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></A
><H2
>Structure Definition</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef union{
  Uint8 type;
  SDL_ActiveEvent active;
  SDL_KeyboardEvent key;
  SDL_MouseMotionEvent motion;
  SDL_MouseButtonEvent button;
  SDL_JoyAxisEvent jaxis;
  SDL_JoyBallEvent jball;
  SDL_JoyHatEvent jhat;
  SDL_JoyButtonEvent jbutton;
  SDL_ResizeEvent resize;
  SDL_ExposeEvent expose;
  SDL_QuitEvent quit;
  SDL_UserEvent user;
  SDL_SywWMEvent syswm;
} SDL_Event;</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3717"
></A
><H2
>Structure Data</H2
><DIV
CLASS="INFORMALTABLE"
><A
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><P
></P
><TABLE
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CLASS="CALSTABLE"
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
></TD
><TD
ALIGN="LEFT"
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>The type of event</TD
></TR
><TR
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><TT
CLASS="STRUCTFIELD"
><I
>active</I
></TT
></TD
><TD
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><A
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>Activation event</A
></TD
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><TR
><TD
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><TT
CLASS="STRUCTFIELD"
><I
>key</I
></TT
></TD
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><A
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>Keyboard event</A
></TD
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><TR
><TD
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><TT
CLASS="STRUCTFIELD"
><I
>motion</I
></TT
></TD
><TD
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><A
HREF="sdlmousemotionevent.html"
>Mouse motion event</A
></TD
></TR
><TR
><TD
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><TT
CLASS="STRUCTFIELD"
><I
>button</I
></TT
></TD
><TD
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><A
HREF="sdlmousebuttonevent.html"
>Mouse button event</A
></TD
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><TT
CLASS="STRUCTFIELD"
><I
>jaxis</I
></TT
></TD
><TD
ALIGN="LEFT"
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><A
HREF="sdljoyaxisevent.html"
>Joystick axis motion event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>jball</I
></TT
></TD
><TD
ALIGN="LEFT"
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><A
HREF="sdljoyballevent.html"
>Joystick trackball motion event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>jhat</I
></TT
></TD
><TD
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><A
HREF="sdljoyhatevent.html"
>Joystick hat motion event</A
></TD
></TR
><TR
><TD
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><TT
CLASS="STRUCTFIELD"
><I
>jbutton</I
></TT
></TD
><TD
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><A
HREF="sdljoybuttonevent.html"
>Joystick button event</A
></TD
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><TT
CLASS="STRUCTFIELD"
><I
>resize</I
></TT
></TD
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>Application window resize event</A
></TD
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><TT
CLASS="STRUCTFIELD"
><I
>expose</I
></TT
></TD
><TD
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><A
HREF="sdlexposeevent.html"
>Application window expose event</A
></TD
></TR
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><TT
CLASS="STRUCTFIELD"
><I
>quit</I
></TT
></TD
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>Application quit request event</A
></TD
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><TT
CLASS="STRUCTFIELD"
><I
>user</I
></TT
></TD
><TD
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><A
HREF="sdluserevent.html"
>User defined event</A
></TD
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><TT
CLASS="STRUCTFIELD"
><I
>syswm</I
></TT
></TD
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>Undefined window manager event</A
></TD
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><A
NAME="AEN3791"
></A
><H2
>Description</H2
><P
>The <SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
> union is the core to all event handling is SDL, its probably the most important structure after <SPAN
CLASS="STRUCTNAME"
>SDL_Surface</SPAN
>. <SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
> is a union of all event structures used in SDL, using it is a simple matter of knowing which union member relates to which event <TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
>.</P
><P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN3799"
></A
><P
></P
><TABLE
BORDER="1"
CLASS="CALSTABLE"
><THEAD
><TR
><TH
ALIGN="LEFT"
VALIGN="TOP"
>Event <TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
></TH
><TH
ALIGN="LEFT"
VALIGN="TOP"
>Event Structure</TH
></TR
></THEAD
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="MIDDLE"
><TT
CLASS="LITERAL"
>SDL_ACTIVEEVENT</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="MIDDLE"
><A
HREF="sdlactiveevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_ActiveEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_KEYDOWN/UP</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlkeyboardevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_KeyboardEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_MOUSEMOTION</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlmousemotionevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_MouseMotionEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_MOUSEBUTTONDOWN/UP</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlmousebuttonevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_MouseButtonEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_JOYAXISMOTION</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdljoyaxisevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_JoyAxisEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_JOYBALLMOTION</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdljoyballevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_JoyBallEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_JOYHATMOTION</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdljoyhatevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_JoyHatEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_JOYBUTTONDOWN/UP</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdljoybuttonevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_JoyButtonEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_QUIT</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlquitevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_QuitEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_SYSWMEVENT</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlsyswmevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_SysWMEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_VIDEORESIZE</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlresizeevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_ResizeEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_VIDEOEXPOSE</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlexposeevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_ExposeEvent</SPAN
></A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_USEREVENT</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdluserevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_UserEvent</SPAN
></A
></TD
></TR
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><P
></P
></DIV
></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3885"
></A
><H2
>Use</H2
><P
>The <SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
> structure has two uses</P
><P
></P
><UL
COMPACT="COMPACT"
><LI
><P
>Reading events on the event queue</P
></LI
><LI
><P
>Placing events on the event queue</P
></LI
></UL
><P
>Reading events from the event queue is done with either <A
HREF="sdlpollevent.html"
><TT
CLASS="FUNCTION"
>SDL_PollEvent</TT
></A
> or <A
HREF="sdlpeepevents.html"
><TT
CLASS="FUNCTION"
>SDL_PeepEvents</TT
></A
>. We'll use <TT
CLASS="FUNCTION"
>SDL_PollEvent</TT
> and step through an example.</P
><P
>First off, we create an empty <SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
> structure.
<PRE
CLASS="PROGRAMLISTING"
>SDL_Event test_event;</PRE
>
<TT
CLASS="FUNCTION"
>SDL_PollEvent</TT
> removes the next event from the event queue, if there are no events on the queue it returns <SPAN
CLASS="RETURNVALUE"
>0</SPAN
> otherwise it returns <SPAN
CLASS="RETURNVALUE"
>1</SPAN
>. We use a <TT
CLASS="FUNCTION"
>while</TT
> loop to process each event in turn.
<PRE
CLASS="PROGRAMLISTING"
>while(SDL_PollEvent(&#38;test_event)) {</PRE
>
The <TT
CLASS="FUNCTION"
>SDL_PollEvent</TT
> function take a pointer to an <SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
> structure that is to be filled with event information. We know that if <TT
CLASS="FUNCTION"
>SDL_PollEvent</TT
> removes an event from the queue then the event information will be placed in our <SPAN
CLASS="STRUCTNAME"
>test_event</SPAN
> structure, but we also know that the <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>type</I
></SPAN
> of event will be placed in the <TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
> member of <SPAN
CLASS="STRUCTNAME"
>test_event</SPAN
>. So to handle each event <TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
> seperately we use a <TT
CLASS="FUNCTION"
>switch</TT
> statement.
<PRE
CLASS="PROGRAMLISTING"
>  switch(test_event.type) {</PRE
>
We need to know what kind of events we're looking for <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>and</I
></SPAN
> the event <TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
>'s of those events. So lets assume we want to detect where the user is moving the mouse pointer within our application. We look through our event types and notice that <TT
CLASS="LITERAL"
>SDL_MOUSEMOTION</TT
> is, more than likely, the event we're looking for. A little <A
HREF="sdlmousemotionevent.html"
>more</A
> research tells use that <TT
CLASS="LITERAL"
>SDL_MOUSEMOTION</TT
> events are handled within the <A
HREF="sdlmousemotionevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_MouseMotionEvent</SPAN
></A
> structure which is the <TT
CLASS="STRUCTFIELD"
><I
>motion</I
></TT
> member of <SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
>. We can check for the <TT
CLASS="LITERAL"
>SDL_MOUSEMOTION</TT
> event <TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
> within our <TT
CLASS="FUNCTION"
>switch</TT
> statement like so:
<PRE
CLASS="PROGRAMLISTING"
>    case SDL_MOUSEMOTION:</PRE
>
All we need do now is read the information out of the <TT
CLASS="STRUCTFIELD"
><I
>motion</I
></TT
> member of <SPAN
CLASS="STRUCTNAME"
>test_event</SPAN
>.
<PRE
CLASS="PROGRAMLISTING"
>      printf("We got a motion event.\n");
      printf("Current mouse position is: (%d, %d)\n", test_event.motion.x, test_event.motion.y);
      break;
    default:
      printf("Unhandled Event!\n");
      break;
  }
}
printf("Event queue empty.\n");</PRE
></P
><P
>It is also possible to push events onto the event queue and so use it as a two-way communication path. Both <A
HREF="sdlpushevent.html"
><TT
CLASS="FUNCTION"
>SDL_PushEvent</TT
></A
> and <A
HREF="sdlpeepevents.html"
><TT
CLASS="FUNCTION"
>SDL_PeepEvents</TT
></A
> allow you to place events onto the event queue. This is usually used to place a <TT
CLASS="LITERAL"
>SDL_USEREVENT</TT
> on the event queue, however you could use it to post fake input events if you wished. Creating your own events is a simple matter of choosing the event type you want, setting the <TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
> member and filling the appropriate member structure with information.
<PRE
CLASS="PROGRAMLISTING"
>SDL_Event user_event;

user_event.type=SDL_USEREVENT;
user_event.user.code=2;
user_event.user.data1=NULL;
user_event.user.data2=NULL;
SDL_PushEvent(&#38;user_event);</PRE
></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3942"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlpollevent.html"
><TT
CLASS="FUNCTION"
>SDL_PollEvent</TT
></A
>,
<A
HREF="sdlpushevent.html"
><TT
CLASS="FUNCTION"
>SDL_PushEvent</TT
></A
>,
<A
HREF="sdlpeepevents.html"
><TT
CLASS="FUNCTION"
>SDL_PeepEvents</TT
></A
></P
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