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| 81 | >Chapter 8. Events</H1 |
| 82 | ><DIV |
| 83 | CLASS="TOC" |
| 84 | ><DL |
| 85 | ><DT |
| 86 | ><B |
| 87 | >Table of Contents</B |
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| 89 | ><DT |
| 90 | ><A |
| 91 | HREF="event.html#AEN3691" |
| 92 | >Introduction</A |
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| 96 | HREF="eventstructures.html" |
| 97 | >SDL Event Structures.</A |
| 98 | ></DT |
| 99 | ><DT |
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| 101 | HREF="eventfunctions.html" |
| 102 | >Event Functions.</A |
| 103 | ></DT |
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| 108 | ><H1 |
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| 112 | ></A |
| 113 | >Introduction</H1 |
| 114 | ><P |
| 115 | >Event handling allows your application to receive input from the user. Event handling is initalised (along with video) with a call to: |
| 116 | <PRE |
| 117 | CLASS="PROGRAMLISTING" |
| 118 | >SDL_Init(SDL_INIT_VIDEO);</PRE |
| 119 | > |
| 120 | Internally, SDL stores all the events waiting to be handled in an event queue. Using functions like <A |
| 121 | HREF="sdlpollevent.html" |
| 122 | ><TT |
| 123 | CLASS="FUNCTION" |
| 124 | >SDL_PollEvent</TT |
| 125 | ></A |
| 126 | > and <A |
| 127 | HREF="sdlpeepevents.html" |
| 128 | ><TT |
| 129 | CLASS="FUNCTION" |
| 130 | >SDL_PeepEvents</TT |
| 131 | ></A |
| 132 | > you can observe and handle waiting input events.</P |
| 133 | ><P |
| 134 | >The key to event handling in SDL is the <A |
| 135 | HREF="sdlevent.html" |
| 136 | ><SPAN |
| 137 | CLASS="STRUCTNAME" |
| 138 | >SDL_Event</SPAN |
| 139 | ></A |
| 140 | > union. The event queue itself is composed of a series of <SPAN |
| 141 | CLASS="STRUCTNAME" |
| 142 | >SDL_Event</SPAN |
| 143 | > unions, one for each waiting event. <SPAN |
| 144 | CLASS="STRUCTNAME" |
| 145 | >SDL_Event</SPAN |
| 146 | > unions are read from the queue with the <TT |
| 147 | CLASS="FUNCTION" |
| 148 | >SDL_PollEvent</TT |
| 149 | > function and it is then up to the application to process the information stored with them.</P |
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| 196 | >SDL_WM_GrabInput</TD |
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| 210 | >SDL Event Structures.</TD |
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