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162a0989 1<div class="pod">
2<!-- INDEX START -->
3<h3 id="TOP">Index</h3>
4
5<ul><li><a href="#NAME">NAME</a></li>
6<li><a href="#SYNOPSIS">SYNOPSIS</a></li>
7<li><a href="#DESCRIPTION">DESCRIPTION</a></li>
8<li><a href="#METHODS">METHODS</a>
9<ul><li><a href="#new">new</a></li>
10<li><a href="#type">type</a></li>
767fbad8 11<li><a href="#Application_visibility_events">Application visibility events</a>
6e0d970b 12<ul><li><a href="#active_gain">active_gain</a></li>
162a0989 13<li><a href="#active_state">active_state</a></li>
14</ul>
15</li>
767fbad8 16<li><a href="#Keyboard_events">Keyboard events</a>
6e0d970b 17<ul><li><a href="#key_state">key_state</a></li>
162a0989 18<li><a href="#key_scancode">key_scancode</a></li>
19<li><a href="#key_sym">key_sym</a></li>
20<li><a href="#key_mod">key_mod</a></li>
21<li><a href="#key_unicode">key_unicode</a></li>
22</ul>
23</li>
767fbad8 24<li><a href="#Mouse_motion_events">Mouse motion events</a>
6e0d970b 25<ul><li><a href="#motion_state">motion_state</a></li>
162a0989 26<li><a href="#motion_x_motion_y">motion_x, motion_y</a></li>
27<li><a href="#motion_xrel_motion_yrel">motion_xrel, motion_yrel</a></li>
28</ul>
29</li>
767fbad8 30<li><a href="#Mouse_button_events">Mouse button events</a>
6e0d970b 31<ul><li><a href="#button_which">button_which</a></li>
162a0989 32<li><a href="#button_button">button_button</a></li>
33<li><a href="#button_state">button_state</a></li>
34<li><a href="#button_x_button_y">button_x, button_y</a></li>
35</ul>
36</li>
767fbad8 37<li><a href="#Joystick_axis_events">Joystick axis events</a>
6e0d970b 38<ul><li><a href="#jaxis_which">jaxis_which</a></li>
162a0989 39<li><a href="#jaxis_axis">jaxis_axis</a></li>
40<li><a href="#jaxis_value">jaxis_value</a></li>
41</ul>
42</li>
767fbad8 43<li><a href="#Joystick_button_events">Joystick button events</a>
6e0d970b 44<ul><li><a href="#jbutton_which">jbutton_which</a></li>
162a0989 45<li><a href="#jbutton_button">jbutton_button</a></li>
46<li><a href="#jbutton_state">jbutton_state</a></li>
47</ul>
48</li>
767fbad8 49<li><a href="#Joystick_hat_events">Joystick hat events</a>
6e0d970b 50<ul><li><a href="#jhat_which">jhat_which</a></li>
162a0989 51<li><a href="#jhat_hat">jhat_hat</a></li>
52<li><a href="#jhat_value">jhat_value</a></li>
53</ul>
54</li>
767fbad8 55<li><a href="#Joystrick_trackball_events">Joystrick trackball events</a>
6e0d970b 56<ul><li><a href="#jball_which">jball_which</a></li>
162a0989 57<li><a href="#jball_ball">jball_ball</a></li>
58<li><a href="#jball_xrel_jball_yrel">jball_xrel, jball_yrel</a></li>
59</ul>
60</li>
767fbad8 61<li><a href="#Window_resize_events">Window resize events</a>
d4446e6e 62<ul><li><a href="#resize_w_resize_h">resize_w, resize_h</a></li>
162a0989 63</ul>
64</li>
767fbad8 65<li><a href="#Window_expose_events">Window expose events</a></li>
66<li><a href="#System_window_manager_events">System window manager events</a>
6e0d970b 67<ul><li><a href="#syswm_msg">syswm_msg</a></li>
162a0989 68</ul>
69</li>
767fbad8 70<li><a href="#User_defined_events">User defined events</a>
6e0d970b 71<ul><li><a href="#user_code">user_code</a></li>
162a0989 72<li><a href="#user_data1_user_data2">user_data1, user_data2</a></li>
73</ul>
74</li>
767fbad8 75<li><a href="#Quit_event">Quit event</a></li>
162a0989 76</ul>
77</li>
78<li><a href="#AUTHOR">AUTHOR</a></li>
79<li><a href="#SEE_ALSO">SEE ALSO</a>
80</li>
81</ul><hr />
82<!-- INDEX END -->
83
84<h1 id="NAME">NAME</h1><p><a href="#TOP" class="toplink">Top</a></p>
85<div id="NAME_CONTENT">
86<p>SDL::Event - General event structure</p>
87
88</div>
89<h1 id="SYNOPSIS">SYNOPSIS</h1><p><a href="#TOP" class="toplink">Top</a></p>
90<div id="SYNOPSIS_CONTENT">
91<pre> use SDL::Event; # for the event object itself
92 use SDL::Events qw(pump_events poll_event); # functions for event queue handling
93
94 SDL::init(SDL_INIT_VIDEO);
95 my $event = SDL::Event-&gt;new();
96
97 while(1)
98 {
99 pump_events();
100
101 if(poll_event($event))
102 {
103 if($event-&gt;type == SDL_MOUSEBUTTONDOWN)
104 {
105 # now you can handle the details
106 $event-&gt;button_which;
107 $event-&gt;button_button;
108 $event-&gt;button_x;
109 $event-&gt;button_y;
110 }
111
112 last if $event-&gt;type == SDL_QUIT;
113 }
114
115 # your screen drawing code will be here
116 }
117
118</pre>
119
120</div>
121<h1 id="DESCRIPTION">DESCRIPTION</h1><p><a href="#TOP" class="toplink">Top</a></p>
122<div id="DESCRIPTION_CONTENT">
123<p>Event handling allows your application to receive input from the user.
124Event handling is initalised (along with video) with a call to:</p>
125<p><code>SDL::init(SDL_INIT_VIDEO);</code></p>
126<p>Internally, SDL stores all the events waiting to be handled in an event queue.
127Using functions like <code>SDL::Events::poll_event()</code>, <code>SDL::Events::peep_events</code>
128and <code>SDL::Events::wait_event()</code> you can observe and handle waiting input events.</p>
129<p>The key to event handling in SDL is the <code>SDL::Event</code> union.
130The event queue itself is composed of a series of <code>SDL::Event</code> unions, one for each waiting event.
131<code>SDL::Event</code> unions are read from the queue with the <code>SDL::Events::poll_event()</code> function
132and it is then up to the application to process the information stored with them. </p>
133
134</div>
135<h1 id="METHODS">METHODS</h1><p><a href="#TOP" class="toplink">Top</a></p>
136<div id="METHODS_CONTENT">
137
138</div>
139<h2 id="new">new</h2>
140<div id="new_CONTENT">
141<p><code>new</code> creates an empty event-object, which can be used store information.
142Either by calling <code>poll_event($event)</code> that transferes one event from the queue into our object
143or by setting all the needed data manually in order to push the event to the queue.</p>
144<pre> use SDL::Event;
145
146 my $event = SDL::Event-&gt;new();
147
148</pre>
149
150</div>
151<h2 id="type">type</h2>
152<div id="type_CONTENT">
153<p>SDL::Event is a union of all event structures used in SDL, using it is a simple matter of knowing
154which union member relates to which event <code>type</code>.</p>
6e0d970b 155<pre> print 'heureka' if $event-&gt;type == SDL_MOUSEBUTTONDOWN;
162a0989 156
157</pre>
158<p>Available type constants:</p>
159<ul>
160 <li><a href="#active">SDL_ACTIVEEVENT</a> - Application visibility event structure </li>
161 <li><a href="#active">SDL_KEYDOWN</a> - Keyboard event structure </li>
162 <li><a href="#active">SDL_KEYUP</a> - Keyboard event structure </li>
163 <li><a href="#active">SDL_MOUSEMOTION</a> - Mouse motion event structure </li>
164 <li><a href="#active">SDL_MOUSEBUTTONDOWN</a> - Mouse button event structure </li>
165 <li><a href="#button">SDL_MOUSEBUTTONUP</a> - Mouse button event structure </li>
166 <li><a href="#active">SDL_JOYAXISMOTION</a> - Joystick axis motion event structure </li>
167 <li><a href="#active">SDL_JOYBALLMOTION</a> - Joystick trackball motion event structure </li>
168 <li><a href="#active">SDL_JOYHATMOTION</a> - Joystick hat position change event structure </li>
169 <li><a href="#active">SDL_JOYBUTTONDOWN</a> - Joystick button event structure </li>
170 <li><a href="#active">SDL_JOYBUTTONUP</a> - Joystick button event structure </li>
171 <li><a href="#active">SDL_VIDEORESIZE</a> - Window resize event structure </li>
172 <li><a href="#active">SDL_VIDEOEXPOSE</a> - Window expose event </li>
173 <li><a href="#active">SDL_QUIT</a> - Quit requested event </li>
174 <li><a href="#active">SDL_USEREVENT</a> - A user-defined event type </li>
175 <li><a href="#active">SDL_SYSWMEVENT</a> - Platform-dependent window manager event. </li>
176</ul>
177
6e0d970b 178<p>Event types are grouped by masks. <code>SDL_EVENTMASK($type)</code> will return the proper mask for the given <code>type</code>.</p>
179<p>Available event mask constants:</p>
180<ul>
181 <li>SDL_ACTIVEEVENTMASK </li>
182 <li>SDL_KEYDOWNMASK </li>
183 <li>SDL_KEYUPMASK </li>
184 <li>SDL_KEYEVENTMASK </li>
185 <li>SDL_MOUSEMOTIONMASK </li>
186 <li>SDL_MOUSEBUTTONDOWNMASK </li>
187 <li>SDL_MOUSEBUTTONUPMASK </li>
188 <li>SDL_MOUSEEVENTMASK </li>
189 <li>SDL_JOYAXISMOTIONMASK </li>
190 <li>SDL_JOYBALLMOTIONMASK </li>
191 <li>SDL_JOYHATMOTIONMASK </li>
192 <li>SDL_JOYBUTTONDOWNMASK </li>
193 <li>SDL_JOYBUTTONUPMASK </li>
194 <li>SDL_JOYEVENTMASK </li>
195 <li>SDL_VIDEORESIZEMASK </li>
196 <li>SDL_VIDEOEXPOSEMASK </li>
197 <li>SDL_QUITMASK </li>
198 <li>SDL_SYSWMEVENTMASK</li>
199</ul>
200
201<p>This way you can check if a given <code>type</code> matches a mask:</p>
202<pre> (SDL_JOYBUTTONDOWN &amp; SDL_MOUSEEVENTMASK) # is false
203 (SDL_MOUSEBUTTONDOWN &amp; SDL_MOUSEEVENTMASK) # is true
204 (SDL_MOUSEBUTTONUP &amp; SDL_MOUSEEVENTMASK) # is true
205 (SDL_MOUSEMOTION &amp; SDL_MOUSEEVENTMASK) # is true
206
207 # and also true is:
208
209 (SDL_MOUSEEVENTMASK == SDL_EVENTMASK(SDL_MOUSEBUTTONDOWN)
210 | SDL_EVENTMASK(SDL_MOUSEBUTTONUP)
211 | SDL_EVENTMASK(SDL_MOUSEMOTION))
212
213</pre>
162a0989 214
215</div>
767fbad8 216<h2 id="Application_visibility_events">Application visibility events</h2>
217<div id="Application_visibility_events_CONTEN">
6e0d970b 218<p><code>active</code> is used when an event of type <code>SDL_ACTIVEEVENT</code> is reported.</p>
162a0989 219<p>When the mouse leaves or enters the window area a <code>SDL_APPMOUSEFOCUS</code> type activation event occurs,
220if the mouse entered the window then <strong>gain</strong> will be 1, otherwise <strong>gain</strong> will be 0. </p>
221<p>A <code>SDL_APPINPUTFOCUS</code> type activation event occurs when the application loses or gains keyboard focus.
222This usually occurs when another application is made active. </p>
223<p>Finally, a <code>SDL_APPACTIVE</code> type event occurs when the application is either minimised/iconified (<strong>gain</strong>=0) or restored. </p>
224<p>A single event can have multiple values set in <strong>state</strong>.</p>
225<p><strong>Note:</strong> This event does not occur when an application window is first created. </p>
226<p>A new ActiveEvent (to fake focus loss) will be created like this:</p>
227<pre> my $event = SDL::Event-&gt;new();
228 $event-&gt;type(SDL_ACTIVEEVENT);
229 $event-&gt;active_gain(0);
230 $event-&gt;active_state(SDL_APPMOUSEFOCUS);
231
232 # I think this is wrong, -&gt;active_type() should get SDL_APPMOUSEFOCUS, but what state gets?
233
234</pre>
235
236</div>
162a0989 237<h3 id="active_gain">active_gain</h3>
238<div id="active_gain_CONTENT">
6e0d970b 239<p>See <code>active</code>. 0 if the event is a loss or 1 if it is a gain.</p>
162a0989 240
241</div>
242<h3 id="active_state">active_state</h3>
243<div id="active_state_CONTENT">
6e0d970b 244<p>A bitmask of the following values: SDL_APPMOUSEFOCUS if mouse focus was gained or lost,
245SDL_APPINPUTFOCUS if input focus was gained or lost, and SDL_APPACTIVE if the application was iconified (gain=0) or restored(gain=1).</p>
162a0989 246
247</div>
767fbad8 248<h2 id="Keyboard_events">Keyboard events</h2>
249<div id="Keyboard_events_CONTENT">
6e0d970b 250<p><code>key</code> is used when an event of type <code>SDL_KEYDOWN</code> or <code>SDL_KEYUP</code> is reported.</p>
251<p>The type and state actually report the same information, they just use different values to do it.
252A keyboard event generally occurs when a key is released (<code>type=SDL_KEYUP</code> or <code>key_state=SDL_RELEASED</code>)
253and when a key is pressed (<code>type=SDL_KEYDOWN</code> or <code>key_state=SDL_PRESSED</code>). </p>
254<p>The <code>SDLK_CAPSLOCK</code> and <code>SDLK_NUMLOCK</code> keys are special cases and report an <code>SDL_KEYDOWN</code> when first pressed,
255then an <code>SDL_RELEASED</code> when released and pressed again. For these keys <code>KEYUP</code> and <code>KEYDOWN</code> events are therefore
256analogous to the state of the caps lock and num lock LEDs rather than the keys themselves.
257These special cases are required for compatibility with Sun workstations.</p>
258<p><strong>Note:</strong> Repeating <code>SDL_KEYDOWN</code> events will occur if key repeat is enabled (see <code>SDL_EnableKeyRepeat</code>). </p>
162a0989 259
260</div>
261<h3 id="key_state">key_state</h3>
262<div id="key_state_CONTENT">
6e0d970b 263<p><code>SDL_PRESSED</code> or <code>SDL_RELEASED</code></p>
162a0989 264
265</div>
266<h3 id="key_scancode">key_scancode</h3>
267<div id="key_scancode_CONTENT">
767fbad8 268<p>The <code>scancode</code> field should generally be left alone, it is the hardware-dependent scancode returned by the keyboard.</p>
162a0989 269
270</div>
271<h3 id="key_sym">key_sym</h3>
272<div id="key_sym_CONTENT">
767fbad8 273<p>The <code>sym</code> field is extremely useful. It is the SDL-defined value of the key (see the keysym definitions in SDLKey).
274This field is very useful when you are checking for certain key presses, like so: </p>
275<pre> while(poll_event($event))
276 {
277 switch($event-&gt;type)
278 {
279 case SDL_KEYDOWN:
280 move_left() if($event-&gt;key_sym == SDLK_LEFT);
281 break;
282 .
283 .
284 .
285 }
286 }
287
288</pre>
162a0989 289
290</div>
291<h3 id="key_mod">key_mod</h3>
292<div id="key_mod_CONTENT">
767fbad8 293<p><code>mod</code> stores the current state of the keyboard modifiers as explained in SDL_GetModState.</p>
162a0989 294
295</div>
296<h3 id="key_unicode">key_unicode</h3>
297<div id="key_unicode_CONTENT">
767fbad8 298<p>The <code>unicode</code> field is only used when UNICODE translation is enabled with SDL_EnableUNICODE.
299If <code>unicode</code> is non-zero then this is the UNICODE character corresponding to the keypress.
300If the high 9 bits of the character are 0, then this maps to the equivalent ASCII character:</p>
301<pre> my $char;
302 if(($event-&gt;key_unicode &amp; 0xFF80) == 0)
303 {
304 $char = $event-&gt;key_unicode &amp; 0x7F;
305 }
306 else
307 {
308 print(&quot;An International Character.\n&quot;);
309 }
310
311</pre>
312<p>UNICODE translation does create a slight overhead so don't enable it unless its needed.</p>
313<p>NOTE: Key release events (SDL_KEYUP) won't necessarily (ever?) contain unicode information.
314See <a href="http://lists.libsdl.org/pipermail/sdl-libsdl.org/2005-January/048355.html">http://lists.libsdl.org/pipermail/sdl-libsdl.org/2005-January/048355.html</a></p>
162a0989 315
316</div>
767fbad8 317<h2 id="Mouse_motion_events">Mouse motion events</h2>
318<div id="Mouse_motion_events_CONTENT">
319<p>Simply put, a SDL_MOUSEMOTION type event occurs when a user moves the mouse within the
320application window or when SDL_WarpMouse is called. Both the absolute (<code>motion_x</code> and <code>motion_y</code>)
321and relative (<code>motion_xrel</code> and <code>motion_yrel</code>) coordinates are reported along with the current
322button states (<code>motion_state</code>).</p>
162a0989 323
324</div>
162a0989 325<h3 id="motion_state">motion_state</h3>
326<div id="motion_state_CONTENT">
767fbad8 327<p>The button state can be interpreted using the <code>SDL_BUTTON</code> macro (see SDL_GetMouseState). </p>
162a0989 328
329</div>
330<h3 id="motion_x_motion_y">motion_x, motion_y</h3>
331<div id="motion_x_motion_y_CONTENT">
767fbad8 332<p>The X/Y coordinates of the mouse</p>
162a0989 333
334</div>
335<h3 id="motion_xrel_motion_yrel">motion_xrel, motion_yrel</h3>
336<div id="motion_xrel_motion_yrel_CONTENT">
767fbad8 337<p>Relative motion in the X/Y direction.</p>
338<p>If the cursor is hidden (SDL_ShowCursor(0)) and the input is grabbed (SDL_WM_GrabInput(SDL_GRAB_ON)),
339then the mouse will give relative motion events even when the cursor reaches the edge of the screen.
340This is currently only implemented on Windows and Linux/Unix-alikes.</p>
162a0989 341
342</div>
767fbad8 343<h2 id="Mouse_button_events">Mouse button events</h2>
344<div id="Mouse_button_events_CONTENT">
345<p>When a mouse button press or release is detected the number of the button pressed (from 1 to 255,
346with 1 usually being the left button and 2 the right) is placed into <code>button_button</code>, the position of the mouse
347when this event occured is stored in the <code>button_x</code> and the <code>button_y</code> fields. Like SDL_KeyboardEvent,
348information on whether the event was a press or a release event is stored in both the <code>button_type</code>
349and <code>button_state</code> fields, but this should be obvious.</p>
350<p>Mouse wheel events are reported as buttons 4 (up) and 5 (down). Two events are generated i.e. you get
351a <code>SDL_MOUSEBUTTONDOWN</code> followed by a <code>SDL_MOUSEBUTTONUP</code> event.</p>
162a0989 352
353</div>
162a0989 354<h3 id="button_which">button_which</h3>
355<div id="button_which_CONTENT">
767fbad8 356<p>The input device index</p>
162a0989 357
358</div>
359<h3 id="button_button">button_button</h3>
360<div id="button_button_CONTENT">
767fbad8 361<p>The mouse button index (<code>SDL_BUTTON_LEFT</code>, <code>SDL_BUTTON_MIDDLE</code>, <code>SDL_BUTTON_RIGHT</code>, <code>SDL_BUTTON_WHEELUP</code>,
362<code>SDL_BUTTON_WHEELDOWN</code>)</p>
162a0989 363
364</div>
365<h3 id="button_state">button_state</h3>
366<div id="button_state_CONTENT">
767fbad8 367<p><code>SDL_PRESSED</code> or <code>SDL_RELEASED</code></p>
162a0989 368
369</div>
370<h3 id="button_x_button_y">button_x, button_y</h3>
371<div id="button_x_button_y_CONTENT">
767fbad8 372<p>The X/Y coordinates of the mouse at press/release time</p>
162a0989 373
374</div>
767fbad8 375<h2 id="Joystick_axis_events">Joystick axis events</h2>
376<div id="Joystick_axis_events_CONTENT">
9be52186 377<p>A <code>SDL_JOYAXISMOTION</code> event occurs whenever a user moves an axis on the joystick.</p>
162a0989 378
379</div>
162a0989 380<h3 id="jaxis_which">jaxis_which</h3>
381<div id="jaxis_which_CONTENT">
9be52186 382<p>The field <code>jaxis_which</code> is the index of the joystick that reported the event.</p>
162a0989 383
384</div>
385<h3 id="jaxis_axis">jaxis_axis</h3>
386<div id="jaxis_axis_CONTENT">
9be52186 387<p>The <code>jaxis_axis</code> is the index of the axis (for a more detailed explaination see the Joystick section).</p>
162a0989 388
389</div>
390<h3 id="jaxis_value">jaxis_value</h3>
391<div id="jaxis_value_CONTENT">
9be52186 392<p><code>jaxis_value</code> is the current position of the axis (range: -32768 to 32767).</p>
162a0989 393
394</div>
767fbad8 395<h2 id="Joystick_button_events">Joystick button events</h2>
396<div id="Joystick_button_events_CONTENT">
9be52186 397<p>A <code>SDL_JOYBUTTONDOWN</code> or <code>SDL_JOYBUTTONUP</code> event occurs when ever a user presses
398or releases a button on a joystick.</p>
162a0989 399
400</div>
162a0989 401<h3 id="jbutton_which">jbutton_which</h3>
402<div id="jbutton_which_CONTENT">
9be52186 403<p>The field <code>jbutton_which</code> is the index of the joystick that reported the event.</p>
162a0989 404
405</div>
406<h3 id="jbutton_button">jbutton_button</h3>
407<div id="jbutton_button_CONTENT">
9be52186 408<p>The <code>jbutton_button</code> is the index of the button (for a more detailed explanation see the Joystick section).</p>
162a0989 409
410</div>
411<h3 id="jbutton_state">jbutton_state</h3>
412<div id="jbutton_state_CONTENT">
9be52186 413<p><code>jbutton_state</code> is the current state of the button which is either <code>jbutton_SDL_PRESSED</code>
414or <code>jbutton_SDL_RELEASED</code>. </p>
162a0989 415
416</div>
767fbad8 417<h2 id="Joystick_hat_events">Joystick hat events</h2>
418<div id="Joystick_hat_events_CONTENT">
9be52186 419<p>A <code>SDL_JOYHATMOTION</code> event occurs when ever a user moves a hat on the joystick. </p>
162a0989 420
421</div>
162a0989 422<h3 id="jhat_which">jhat_which</h3>
423<div id="jhat_which_CONTENT">
9be52186 424<p>The field <code>jhat_which</code> is the index of the joystick that reported the event.</p>
162a0989 425
426</div>
427<h3 id="jhat_hat">jhat_hat</h3>
428<div id="jhat_hat_CONTENT">
9be52186 429<p><code>jhat_hat</code> is the index of the hat (for a more detailed explanation see the Joystick section).</p>
162a0989 430
431</div>
432<h3 id="jhat_value">jhat_value</h3>
433<div id="jhat_value_CONTENT">
9be52186 434<p><code>jhat_value</code> is the current position of the hat. It is a bitwise OR'd combination of the following
435values (whose meanings should be pretty obvious):</p>
436<ul>
437 <li><code>SDL_HAT_CENTERED</code> </li>
438 <li><code>SDL_HAT_UP</code> </li>
439 <li><code>SDL_HAT_RIGHT</code> </li>
440 <li><code>SDL_HAT_DOWN</code> </li>
441 <li><code>SDL_HAT_LEFT</code></li>
442</ul>
443
444<p>The following defines are also provided:</p>
445<ul>
446 <li><code>SDL_HAT_RIGHTUP</code> </li>
447 <li><code>SDL_HAT_RIGHTDOWN</code> </li>
448 <li><code>SDL_HAT_LEFTUP</code> </li>
449 <li><code>SDL_HAT_LEFTDOWN</code></li>
450</ul>
451
162a0989 452
453</div>
767fbad8 454<h2 id="Joystrick_trackball_events">Joystrick trackball events</h2>
455<div id="Joystrick_trackball_events_CONTENT">
9be52186 456<p>A <code>SDL_JOYBALLMOTION</code> event occurs when a user moves a trackball on the joystick.</p>
162a0989 457
458</div>
162a0989 459<h3 id="jball_which">jball_which</h3>
460<div id="jball_which_CONTENT">
9be52186 461<p>The field <code>jball_which</code> is the index of the joystick that reported the event.</p>
162a0989 462
463</div>
464<h3 id="jball_ball">jball_ball</h3>
465<div id="jball_ball_CONTENT">
9be52186 466<p><code>jball_ball</code> is the index of the trackball (for a more detailed explanation see the Joystick section).</p>
162a0989 467
468</div>
469<h3 id="jball_xrel_jball_yrel">jball_xrel, jball_yrel</h3>
470<div id="jball_xrel_jball_yrel_CONTENT">
9be52186 471<p>Trackballs only return relative motion, this is the change in position on the ball since it was last
472polled (last cycle of the event loop) and it is stored in <code>jball_xrel</code> and <code>jball_yrel</code>.</p>
162a0989 473
474</div>
767fbad8 475<h2 id="Window_resize_events">Window resize events</h2>
476<div id="Window_resize_events_CONTENT">
162a0989 477
478</div>
d4446e6e 479<h3 id="resize_w_resize_h">resize_w, resize_h</h3>
480<div id="resize_w_resize_h_CONTENT">
481<p>When <code>SDL_RESIZABLE</code> is passed as a flag to <code>SDL_SetVideoMode</code> the user is allowed to resize the
482applications window. When the window is resized an <code>SDL_VIDEORESIZE</code> is reported, with the new
483window width and height values stored in the resize structure's <code>resize_w</code> and <code>resize_h</code>.
484When an <code>SDL_VIDEORESIZE</code> is received the window should be resized to the new dimensions using
485SDL_SetVideoMode. </p>
162a0989 486
487</div>
767fbad8 488<h2 id="Window_expose_events">Window expose events</h2>
489<div id="Window_expose_events_CONTENT">
d4446e6e 490<p>A <code>VIDEOEXPOSE</code> event is triggered when the screen has been modified outside of the application,
491usually by the window manager and needs to be redrawn.</p>
162a0989 492
493</div>
767fbad8 494<h2 id="System_window_manager_events">System window manager events</h2>
495<div id="System_window_manager_events_CONTENT">
d4446e6e 496<p>The system window manager event contains a system-specific information about unknown window manager
497events. If you enable this event using <code>SDL_EventState</code>, it will be generated whenever unhandled
498events are received from the window manager. This can be used, for example, to implement cut-and-paste
499in your application.</p>
500<p>If you want to obtain system-specific information about the window manager, you can fill in the
501version member of a SDL_SysWMinfo structure (details can be found in SDL_syswm.h, which must be included)
502using the SDL_VERSION() macro found in SDL_version.h, and pass it to the function:</p>
503<pre> int SDL_GetWMInfo(SDL_SysWMinfo *info);
504
505</pre>
506<p>See <a href="http://www.libsdl.org/cgi/docwiki.cgi/SDL_SysWMEvent">http://www.libsdl.org/cgi/docwiki.cgi/SDL_SysWMEvent</a></p>
162a0989 507
508</div>
162a0989 509<h3 id="syswm_msg">syswm_msg</h3>
510<div id="syswm_msg_CONTENT">
511
512</div>
767fbad8 513<h2 id="User_defined_events">User defined events</h2>
514<div id="User_defined_events_CONTENT">
d4446e6e 515<p>This event is unique, it is never created by SDL but only by the user. The event can be pushed onto
516the event queue using <code>SDL::Events::push_event</code>. The contents of the structure members are completely up to the
517programmer, the only requirement is that type is a value from <code>SDL_USEREVENT</code> to <code>SDL_NUMEVENTS-1</code> (inclusive)</p>
518<pre> my $event = SDL::Event-&gt;new();
519 $event-&gt;type ( SDL_USEREVENT + 3 );
520 $event-&gt;event_code(10);
521 $event-&gt;data1('hello event');
522
523 SDL::Events::push_event($event);
524
525</pre>
162a0989 526
527</div>
162a0989 528<h3 id="user_code">user_code</h3>
529<div id="user_code_CONTENT">
d4446e6e 530<p>User defined event code (integer).</p>
162a0989 531
532</div>
533<h3 id="user_data1_user_data2">user_data1, user_data2</h3>
534<div id="user_data1_user_data2_CONTENT">
d4446e6e 535<p>User defined data.</p>
162a0989 536
537</div>
767fbad8 538<h2 id="Quit_event">Quit event</h2>
539<div id="Quit_event_CONTENT">
d4446e6e 540<p>As can be seen, the <code>SDL_QuitEvent</code> structure serves no useful purpose. The event itself, on the other hand,
541is very important. If you filter out or ignore a quit event then it is impossible for the user to close the
542window. On the other hand, if you do accept a quit event then the application window will be closed, and
543screen updates will still report success even though the application will no longer be visible.</p>
544<p><strong>Note</strong>: The macro SDL_QuitRequested will return non-zero if a quit event is pending </p>
162a0989 545
546</div>
547<h1 id="AUTHOR">AUTHOR</h1><p><a href="#TOP" class="toplink">Top</a></p>
548<div id="AUTHOR_CONTENT">
549
550</div>
551<h1 id="SEE_ALSO">SEE ALSO</h1><p><a href="#TOP" class="toplink">Top</a></p>
552<div id="SEE_ALSO_CONTENT">
553<p><cite>perl</cite></p>
554
555</div>
556</div>