Mercurial > sdl-ios-xcode
annotate docs/html/sdlsemwaittimeout.html @ 1629:ef4a796e7f24
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 |
rev | line source |
---|---|
0 | 1 <HTML |
2 ><HEAD | |
3 ><TITLE | |
4 >SDL_SemWaitTimeout</TITLE | |
5 ><META | |
6 NAME="GENERATOR" | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
7 CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ |
0 | 8 "><LINK |
9 REL="HOME" | |
10 TITLE="SDL Library Documentation" | |
11 HREF="index.html"><LINK | |
12 REL="UP" | |
13 TITLE="Multi-threaded Programming" | |
14 HREF="thread.html"><LINK | |
15 REL="PREVIOUS" | |
16 TITLE="SDL_SemTryWait" | |
17 HREF="sdlsemtrywait.html"><LINK | |
18 REL="NEXT" | |
19 TITLE="SDL_SemPost" | |
20 HREF="sdlsempost.html"></HEAD | |
21 ><BODY | |
22 CLASS="REFENTRY" | |
23 BGCOLOR="#FFF8DC" | |
24 TEXT="#000000" | |
25 LINK="#0000ee" | |
26 VLINK="#551a8b" | |
27 ALINK="#ff0000" | |
28 ><DIV | |
29 CLASS="NAVHEADER" | |
30 ><TABLE | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
31 SUMMARY="Header navigation table" |
0 | 32 WIDTH="100%" |
33 BORDER="0" | |
34 CELLPADDING="0" | |
35 CELLSPACING="0" | |
36 ><TR | |
37 ><TH | |
38 COLSPAN="3" | |
39 ALIGN="center" | |
40 >SDL Library Documentation</TH | |
41 ></TR | |
42 ><TR | |
43 ><TD | |
44 WIDTH="10%" | |
45 ALIGN="left" | |
46 VALIGN="bottom" | |
47 ><A | |
48 HREF="sdlsemtrywait.html" | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
49 ACCESSKEY="P" |
0 | 50 >Prev</A |
51 ></TD | |
52 ><TD | |
53 WIDTH="80%" | |
54 ALIGN="center" | |
55 VALIGN="bottom" | |
56 ></TD | |
57 ><TD | |
58 WIDTH="10%" | |
59 ALIGN="right" | |
60 VALIGN="bottom" | |
61 ><A | |
62 HREF="sdlsempost.html" | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
63 ACCESSKEY="N" |
0 | 64 >Next</A |
65 ></TD | |
66 ></TR | |
67 ></TABLE | |
68 ><HR | |
69 ALIGN="LEFT" | |
70 WIDTH="100%"></DIV | |
71 ><H1 | |
72 ><A | |
73 NAME="SDLSEMWAITTIMEOUT" | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
74 ></A |
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
75 >SDL_SemWaitTimeout</H1 |
0 | 76 ><DIV |
77 CLASS="REFNAMEDIV" | |
78 ><A | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
79 NAME="AEN8120" |
0 | 80 ></A |
81 ><H2 | |
82 >Name</H2 | |
83 >SDL_SemWaitTimeout -- Lock a semaphore, but only wait up to a specified maximum time.</DIV | |
84 ><DIV | |
85 CLASS="REFSYNOPSISDIV" | |
86 ><A | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
87 NAME="AEN8123" |
0 | 88 ></A |
89 ><H2 | |
90 >Synopsis</H2 | |
91 ><DIV | |
92 CLASS="FUNCSYNOPSIS" | |
93 ><A | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
94 NAME="AEN8124" |
0 | 95 ></A |
96 ><P | |
97 ></P | |
98 ><PRE | |
99 CLASS="FUNCSYNOPSISINFO" | |
100 >#include "SDL.h" | |
101 #include "SDL_thread.h"</PRE | |
102 ><P | |
103 ><CODE | |
104 ><CODE | |
105 CLASS="FUNCDEF" | |
106 >int <B | |
107 CLASS="FSFUNC" | |
108 >SDL_SemWaitTimeout</B | |
109 ></CODE | |
110 >(SDL_sem *sem, Uint32 timeout);</CODE | |
111 ></P | |
112 ><P | |
113 ></P | |
114 ></DIV | |
115 ></DIV | |
116 ><DIV | |
117 CLASS="REFSECT1" | |
118 ><A | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
119 NAME="AEN8130" |
0 | 120 ></A |
121 ><H2 | |
122 >Description</H2 | |
123 ><P | |
124 ><TT | |
125 CLASS="FUNCTION" | |
126 >SDL_SemWaitTimeout()</TT | |
127 > is a varient of | |
128 <A | |
129 HREF="sdlsemwait.html" | |
130 >SDL_SemWait</A | |
131 > | |
132 with a maximum timeout value. | |
133 If the value of the semaphore pointed to by <TT | |
134 CLASS="PARAMETER" | |
135 ><I | |
136 >sem</I | |
137 ></TT | |
138 > is | |
139 positive (greater than zero) it will atomically decrement the semaphore value | |
140 and return 0, otherwise it will wait up to <TT | |
141 CLASS="PARAMETER" | |
142 ><I | |
143 >timeout</I | |
144 ></TT | |
145 > | |
146 milliseconds trying to lock the semaphore. This function is to be avoided if | |
147 possible since on some platforms it is implemented by polling the semaphore | |
148 every millisecond in a busy loop.</P | |
149 ><P | |
150 >After <TT | |
151 CLASS="FUNCTION" | |
152 >SDL_SemWaitTimeout()</TT | |
153 > is successful, the semaphore | |
154 can be released and its count atomically incremented by a successful call to | |
155 <A | |
156 HREF="sdlsempost.html" | |
157 >SDL_SemPost</A | |
158 >.</P | |
159 ></DIV | |
160 ><DIV | |
161 CLASS="REFSECT1" | |
162 ><A | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
163 NAME="AEN8140" |
0 | 164 ></A |
165 ><H2 | |
166 >Return Value</H2 | |
167 ><P | |
168 >Returns <SPAN | |
169 CLASS="RETURNVALUE" | |
170 >0</SPAN | |
171 > if the semaphore was successfully locked or | |
172 either <SPAN | |
173 CLASS="RETURNVALUE" | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
174 >SDL_MUTEX_TIMEDOUT</SPAN |
0 | 175 > or <SPAN |
176 CLASS="RETURNVALUE" | |
177 >-1</SPAN | |
178 > | |
179 if the timeout period was exceeded or there was an error, respectivly.</P | |
180 ><P | |
181 >If the semaphore was not successfully locked, the semaphore will be unchanged.</P | |
182 ></DIV | |
183 ><DIV | |
184 CLASS="REFSECT1" | |
185 ><A | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
186 NAME="AEN8147" |
0 | 187 ></A |
188 ><H2 | |
189 >Examples</H2 | |
190 ><P | |
191 ><PRE | |
192 CLASS="PROGRAMLISTING" | |
193 >res = SDL_SemWaitTimeout(my_sem, WAIT_TIMEOUT_MILLISEC); | |
194 | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
195 if (res == SDL_MUTEX_TIMEDOUT) { |
0 | 196 return TRY_AGAIN; |
197 } | |
198 if (res == -1) { | |
199 return WAIT_ERROR; | |
200 } | |
201 | |
202 ... | |
203 | |
204 SDL_SemPost(my_sem);</PRE | |
205 ></P | |
206 ></DIV | |
207 ><DIV | |
208 CLASS="REFSECT1" | |
209 ><A | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
210 NAME="AEN8151" |
0 | 211 ></A |
212 ><H2 | |
213 >See Also</H2 | |
214 ><P | |
215 ><A | |
216 HREF="sdlcreatesemaphore.html" | |
217 ><TT | |
218 CLASS="FUNCTION" | |
219 >SDL_CreateSemaphore</TT | |
220 ></A | |
221 >, | |
222 <A | |
223 HREF="sdldestroysemaphore.html" | |
224 ><TT | |
225 CLASS="FUNCTION" | |
226 >SDL_DestroySemaphore</TT | |
227 ></A | |
228 >, | |
229 <A | |
230 HREF="sdlsemwait.html" | |
231 ><TT | |
232 CLASS="FUNCTION" | |
233 >SDL_SemWait</TT | |
234 ></A | |
235 >, | |
236 <A | |
237 HREF="sdlsemtrywait.html" | |
238 ><TT | |
239 CLASS="FUNCTION" | |
240 >SDL_SemTryWait</TT | |
241 ></A | |
242 >, | |
243 <A | |
244 HREF="sdlsempost.html" | |
245 ><TT | |
246 CLASS="FUNCTION" | |
247 >SDL_SemPost</TT | |
248 ></A | |
249 >, | |
250 <A | |
251 HREF="sdlsemvalue.html" | |
252 ><TT | |
253 CLASS="FUNCTION" | |
254 >SDL_SemValue</TT | |
255 ></A | |
256 ></P | |
257 ></DIV | |
258 ><DIV | |
259 CLASS="NAVFOOTER" | |
260 ><HR | |
261 ALIGN="LEFT" | |
262 WIDTH="100%"><TABLE | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
263 SUMMARY="Footer navigation table" |
0 | 264 WIDTH="100%" |
265 BORDER="0" | |
266 CELLPADDING="0" | |
267 CELLSPACING="0" | |
268 ><TR | |
269 ><TD | |
270 WIDTH="33%" | |
271 ALIGN="left" | |
272 VALIGN="top" | |
273 ><A | |
274 HREF="sdlsemtrywait.html" | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
275 ACCESSKEY="P" |
0 | 276 >Prev</A |
277 ></TD | |
278 ><TD | |
279 WIDTH="34%" | |
280 ALIGN="center" | |
281 VALIGN="top" | |
282 ><A | |
283 HREF="index.html" | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
284 ACCESSKEY="H" |
0 | 285 >Home</A |
286 ></TD | |
287 ><TD | |
288 WIDTH="33%" | |
289 ALIGN="right" | |
290 VALIGN="top" | |
291 ><A | |
292 HREF="sdlsempost.html" | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
293 ACCESSKEY="N" |
0 | 294 >Next</A |
295 ></TD | |
296 ></TR | |
297 ><TR | |
298 ><TD | |
299 WIDTH="33%" | |
300 ALIGN="left" | |
301 VALIGN="top" | |
302 >SDL_SemTryWait</TD | |
303 ><TD | |
304 WIDTH="34%" | |
305 ALIGN="center" | |
306 VALIGN="top" | |
307 ><A | |
308 HREF="thread.html" | |
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
309 ACCESSKEY="U" |
0 | 310 >Up</A |
311 ></TD | |
312 ><TD | |
313 WIDTH="33%" | |
314 ALIGN="right" | |
315 VALIGN="top" | |
316 >SDL_SemPost</TD | |
317 ></TR | |
318 ></TABLE | |
319 ></DIV | |
320 ></BODY | |
321 ></HTML | |
322 > |