Mercurial > sdl-ios-xcode
annotate docs/man3/SDL_Event.3 @ 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 | e5bc29de3f0a |
children | 85cbe9c892f4 |
rev | line source |
---|---|
181
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parents:
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1 .TH "SDL_Event" "3" "Tue 11 Sep 2001, 22:59" "SDL" "SDL API Reference" |
0 | 2 .SH "NAME" |
3 SDL_Event\- General event structure | |
4 .SH "STRUCTURE DEFINITION" | |
5 .PP | |
6 .nf | |
7 \f(CWtypedef union{ | |
8 Uint8 type; | |
9 SDL_ActiveEvent active; | |
10 SDL_KeyboardEvent key; | |
11 SDL_MouseMotionEvent motion; | |
12 SDL_MouseButtonEvent button; | |
13 SDL_JoyAxisEvent jaxis; | |
14 SDL_JoyBallEvent jball; | |
15 SDL_JoyHatEvent jhat; | |
16 SDL_JoyButtonEvent jbutton; | |
17 SDL_ResizeEvent resize; | |
181
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18 SDL_ExposeEvent expose; |
0 | 19 SDL_QuitEvent quit; |
20 SDL_UserEvent user; | |
21 SDL_SywWMEvent syswm; | |
22 } SDL_Event;\fR | |
23 .fi | |
24 .PP | |
25 .SH "STRUCTURE DATA" | |
26 .TP 20 | |
27 \fBtype\fR | |
28 The type of event | |
29 .TP 20 | |
30 \fBactive\fR | |
31 \fIActivation event\fR | |
32 .TP 20 | |
33 \fBkey\fR | |
34 \fIKeyboard event\fR | |
35 .TP 20 | |
36 \fBmotion\fR | |
37 \fIMouse motion event\fR | |
38 .TP 20 | |
39 \fBbutton\fR | |
40 \fIMouse button event\fR | |
41 .TP 20 | |
42 \fBjaxis\fR | |
43 \fIJoystick axis motion event\fR | |
44 .TP 20 | |
45 \fBjball\fR | |
46 \fIJoystick trackball motion event\fR | |
47 .TP 20 | |
48 \fBjhat\fR | |
49 \fIJoystick hat motion event\fR | |
50 .TP 20 | |
51 \fBjbutton\fR | |
52 \fIJoystick button event\fR | |
53 .TP 20 | |
54 \fBresize\fR | |
55 \fIApplication window resize event\fR | |
56 .TP 20 | |
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57 \fBexpose\fR |
e5bc29de3f0a
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58 \fIApplication window expose event\fR |
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59 .TP 20 |
0 | 60 \fBquit\fR |
61 \fIApplication quit request event\fR | |
62 .TP 20 | |
63 \fBuser\fR | |
64 \fIUser defined event\fR | |
65 .TP 20 | |
66 \fBsyswm\fR | |
67 \fIUndefined window manager event\fR | |
68 .SH "DESCRIPTION" | |
69 .PP | |
70 The \fBSDL_Event\fR union is the core to all event handling is SDL, its probably the most important structure after \fBSDL_Surface\fR\&. \fBSDL_Event\fR 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 \fBtype\fR\&. | |
71 .PP | |
72 .TP 20 | |
73 \fBEvent \fBtype\fR\fR | |
74 \fBEvent Structure\fR | |
75 .TP 20 | |
76 \fBSDL_ACTIVEEVENT\fP | |
77 \fI\fBSDL_ActiveEvent\fR\fR | |
78 .TP 20 | |
79 \fBSDL_KEYDOWN/UP\fP | |
80 \fI\fBSDL_KeyboardEvent\fR\fR | |
81 .TP 20 | |
82 \fBSDL_MOUSEMOTION\fP | |
83 \fI\fBSDL_MouseMotionEvent\fR\fR | |
84 .TP 20 | |
85 \fBSDL_MOUSEBUTTONDOWN/UP\fP | |
86 \fI\fBSDL_MouseButtonEvent\fR\fR | |
87 .TP 20 | |
88 \fBSDL_JOYAXISMOTION\fP | |
89 \fI\fBSDL_JoyAxisEvent\fR\fR | |
90 .TP 20 | |
91 \fBSDL_JOYBALLMOTION\fP | |
92 \fI\fBSDL_JoyBallEvent\fR\fR | |
93 .TP 20 | |
94 \fBSDL_JOYHATMOTION\fP | |
95 \fI\fBSDL_JoyHatEvent\fR\fR | |
96 .TP 20 | |
97 \fBSDL_JOYBUTTONDOWN/UP\fP | |
98 \fI\fBSDL_JoyButtonEvent\fR\fR | |
99 .TP 20 | |
100 \fBSDL_QUIT\fP | |
101 \fI\fBSDL_QuitEvent\fR\fR | |
102 .TP 20 | |
103 \fBSDL_SYSWMEVENT\fP | |
104 \fI\fBSDL_SysWMEvent\fR\fR | |
105 .TP 20 | |
106 \fBSDL_VIDEORESIZE\fP | |
107 \fI\fBSDL_ResizeEvent\fR\fR | |
108 .TP 20 | |
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109 \fBSDL_VIDEOEXPOSE\fP |
e5bc29de3f0a
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parents:
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110 \fI\fBSDL_ExposeEvent\fR\fR |
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parents:
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111 .TP 20 |
0 | 112 \fBSDL_USEREVENT\fP |
113 \fI\fBSDL_UserEvent\fR\fR | |
114 .SH "USE" | |
115 .PP | |
116 The \fBSDL_Event\fR structure has two uses | |
117 .IP " \(bu" 6 | |
118 Reading events on the event queue | |
119 .IP " \(bu" 6 | |
120 Placing events on the event queue | |
121 .PP | |
122 Reading events from the event queue is done with either \fI\fBSDL_PollEvent\fP\fR or \fI\fBSDL_PeepEvents\fP\fR\&. We\&'ll use \fBSDL_PollEvent\fP and step through an example\&. | |
123 .PP | |
124 First off, we create an empty \fBSDL_Event\fR structure\&. | |
125 .PP | |
126 .nf | |
127 \f(CWSDL_Event test_event;\fR | |
128 .fi | |
129 .PP | |
130 \fBSDL_PollEvent\fP removes the next event from the event queue, if there are no events on the queue it returns \fB0\fR otherwise it returns \fB1\fR\&. We use a \fBwhile\fP loop to process each event in turn\&. | |
131 .PP | |
132 .nf | |
133 \f(CWwhile(SDL_PollEvent(&test_event)) {\fR | |
134 .fi | |
135 .PP | |
136 The \fBSDL_PollEvent\fP function take a pointer to an \fBSDL_Event\fR structure that is to be filled with event information\&. We know that if \fBSDL_PollEvent\fP removes an event from the queue then the event information will be placed in our \fBtest_event\fR structure, but we also know that the \fItype\fP of event will be placed in the \fBtype\fR member of \fBtest_event\fR\&. So to handle each event \fBtype\fR seperately we use a \fBswitch\fP statement\&. | |
137 .PP | |
138 .nf | |
139 \f(CW switch(test_event\&.type) {\fR | |
140 .fi | |
141 .PP | |
142 We need to know what kind of events we\&'re looking for \fIand\fP the event \fBtype\fR\&'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 \fBSDL_MOUSEMOTION\fP is, more than likely, the event we\&'re looking for\&. A little \fImore\fR research tells use that \fBSDL_MOUSEMOTION\fP events are handled within the \fI\fBSDL_MouseMotionEvent\fR\fR structure which is the \fBmotion\fR member of \fBSDL_Event\fR\&. We can check for the \fBSDL_MOUSEMOTION\fP event \fBtype\fR within our \fBswitch\fP statement like so: | |
143 .PP | |
144 .nf | |
145 \f(CW case SDL_MOUSEMOTION:\fR | |
146 .fi | |
147 .PP | |
148 All we need do now is read the information out of the \fBmotion\fR member of \fBtest_event\fR\&. | |
149 .PP | |
150 .nf | |
151 \f(CW printf("We got a motion event\&. | |
152 "); | |
153 printf("Current mouse position is: (%d, %d) | |
154 ", test_event\&.motion\&.x, test_event\&.motion\&.y); | |
155 break; | |
156 default: | |
157 printf("Unhandled Event! | |
158 "); | |
159 break; | |
160 } | |
161 } | |
162 printf("Event queue empty\&. | |
163 ");\fR | |
164 .fi | |
165 .PP | |
166 .PP | |
167 It is also possible to push events onto the event queue and so use it as a two-way communication path\&. Both \fI\fBSDL_PushEvent\fP\fR and \fI\fBSDL_PeepEvents\fP\fR allow you to place events onto the event queue\&. This is usually used to place a \fBSDL_USEREVENT\fP 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 \fBtype\fR member and filling the appropriate member structure with information\&. | |
168 .PP | |
169 .nf | |
170 \f(CWSDL_Event user_event; | |
171 | |
172 user_event\&.type=SDL_USEREVENT; | |
173 user_event\&.user\&.code=2; | |
174 user_event\&.user\&.data1=NULL; | |
175 user_event\&.user\&.data2=NULL; | |
176 SDL_PushEvent(&user_event);\fR | |
177 .fi | |
178 .PP | |
179 .SH "SEE ALSO" | |
180 .PP | |
181 \fI\fBSDL_PollEvent\fP\fR, \fI\fBSDL_PushEvent\fP\fR, \fI\fBSDL_PeepEvents\fP\fR | |
181
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182 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 22:59 |