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81 | >Chapter 8. Events</H1 |
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84 | ><DL |
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86 | ><B |
87 | >Table of Contents</B |
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90 | ><A |
91 | HREF="event.html#AEN3691" |
92 | >Introduction</A |
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97 | >SDL Event Structures.</A |
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102 | >Event Functions.</A |
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108 | ><H1 |
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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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