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Date: Sat, 16 Aug 2003 16:22:56 +0300 From: "Mike Gorchak" Subject: Package building for QNX6 I'm just completed the package description file for QNX6 - qpg, it is like a\ .spec files for Linux. Please place SDL.qpg.in file in the root of the proj\ ect, where .spec file is placed. And sdl12qpg.diff - just adding the SDL.qpg\ .in. The same for the SDL_image. I'm planning to add .qpg files creation for\ all SDL* projects. As for shared library building for QNX6. It is very hard to improve the exis\ ting libtool code to support QNX shared libraries. Much easyiest is to remov\ e libtool.m4 code from the acinclude.m4 for those persons, who building shar\ ed libraries for QNX6. I'm described all what they need to do with .so under\ QNX6 in the README.QNX file. And 90% of people used the precompiled librari\ es, so I think it is not big problem :)
author Sam Lantinga <slouken@libsdl.org>
date Sat, 23 Aug 2003 23:25:46 +0000
parents e5bc29de3f0a
children 355632dca928
line wrap: on
line source

<HTML
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>SDL_Event</TITLE
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><H1
><A
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>SDL_Event</A
></H1
><DIV
CLASS="REFNAMEDIV"
><A
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></A
><H2
>Name</H2
>SDL_Event&nbsp;--&nbsp;General event structure</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3330"
></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="AEN3333"
></A
><H2
>Structure Data</H2
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN3335"
></A
><P
></P
><TABLE
BORDER="0"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>The type of event</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>active</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlactiveevent.html"
>Activation event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>key</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlkeyboardevent.html"
>Keyboard event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>motion</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlmousemotionevent.html"
>Mouse motion event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>button</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlmousebuttonevent.html"
>Mouse button event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>jaxis</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><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"
VALIGN="TOP"
><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
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdljoyhatevent.html"
>Joystick hat motion event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>jbutton</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdljoybuttonevent.html"
>Joystick button event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>resize</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlresizeevent.html"
>Application window resize event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>expose</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlexposeevent.html"
>Application window expose event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>quit</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlquitevent.html"
>Application quit request event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>user</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdluserevent.html"
>User defined event</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>syswm</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="sdlsyswmevent.html"
>Undefined window manager event</A
></TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3407"
></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="AEN3415"
></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
></TBODY
></TABLE
><P
></P
></DIV
></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3501"
></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 <I
CLASS="EMPHASIS"
>type</I
> 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 <I
CLASS="EMPHASIS"
>and</I
> 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="AEN3558"
></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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