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event queue never empty
William Labbett
Member #4,486
March 2004
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I spent a while getting the formatting correct but when I paste it here it goes wrong and when I paste into Notepad it goes wrong.

Anyway, the code below doesn't work because al_is_event_queue_empty() always returns 0 so the drawing never happens.

This was working a few days ago. I added a bit of code and nw it's broken.

I'v got no clue as to why the queue is never empty.

Any ideas ?

Using Win7.

#SelectExpand
1 2 3int main() 4{ 5 6 OneRun OneRunObject = OneRun(); 7 8 if( OneRunObject.InitOkay() == false) 9 { 10 game_log(MAIN_LOG, "Problem initialising game.\n"); 11 pause_and_quit 12 } 13 14 15 16 Menu MainMenu("main_menu_bitmap_list.txt", "game_data/menu_bitmaps"); 17 18 Menu *CurrentMenu; 19 20 int cm_id = MAIN_MENU; /* current menu identifier */ 21 22 bool need_redraw = false; 23 bool hold_on_key_down_events = false; 24 bool close_menu = false; 25 26 int time; 27 28 int update_done = 0; 29 30 int time_of_key_down; 31 32 while( OneRunObject.ClearUpAndQuit() == false) 33 { 34 switch(cm_id) 35 { 36 case MAIN_MENU: 37 CurrentMenu = &MainMenu; 38 break; 39 } 40 41 al_wait_for_event(OneRunObject.q, &OneRunObject.event); 42 switch(OneRunObject.event.type) 43 { 44 case ALLEGRO_EVENT_DISPLAY_CLOSE: 45 pf("display close.\n"); 46 47 OneRunObject.SetClearUpAndQuitFlag(); 48 CurrentMenu->SetNeedToActFlag(); 49 break; 50 case ALLEGRO_EVENT_KEY_DOWN: 51 52 printf("key down.\n"); 53 54 if(hold_on_key_down_events == false) 55 { 56 OneRunObject.SetKeyState(ALLEGRO_EVENT_KEY_DOWN); 57 } 58 59 break; 60 case ALLEGRO_EVENT_KEY_UP: 61 printf("key up.\n"); 62 OneRunObject.SetKeyState(ALLEGRO_EVENT_KEY_UP); 63 break; 64 case ALLEGRO_EVENT_TIMER: 65 pf("timer tick\n"); 66 need_redraw = true; 67 68 if(hold_on_key_down_events == false) 69 { 70 update_done = CurrentMenu->Update(OneRunObject.key_states); 71 } 72 73 if(update_done == 1 && hold_on_key_down_events == false) /* key down processed */ 74 { 75 hold_on_key_down_events = true; 76 time_of_key_down = al_get_timer_count(OneRunObject.timer); 77 } 78 else if(update_done == 2) /* Enter key pressed. */ 79 { 80 if(cm_id == MAIN_MENU) 81 { 82 switch(CurrentMenu->OptionSelected()) 83 { 84 case 0: /* Play. */ 85 OneRunObject.time_to_play = true; 86 break; 87 case 1: 88 cm_id = CONTROL_OPTIONS; 89 close_menu = true; 90 CurrentMenu->SetCloseTime(al_get_timer_count(OneRunObject.timer)); 91 break; 92 93 } 94 } 95 96 97 } 98 99 if(hold_on_key_down_events == true && al_get_timer_count(OneRunObject.timer) >= time_of_key_down + 20) 100 { 101 hold_on_key_down_events = false; 102 } 103 104 break; 105 default: 106 pf("some other event.\n\n"); 107 break; 108 109 } /* switch(OneRunObject.event.type) */ 110 111 112 pf("need redraw = %s empty = %d", need_redraw ? "TRUE" : "FALSE", (int) al_is_event_queue_empty(OneRunObject.q)); 113 114 if(need_redraw == true && al_is_event_queue_empty(OneRunObject.q)) 115 { 116 printf("calling\n"); 117 CurrentMenu->DrawMenu(close_menu, al_get_timer_count(OneRunObject.timer)); 118 } 119 120 pf("\n"); 121 122 123 if(OneRunObject.time_to_play == true) 124 { 125 /* if a loaded game was chosen, it should already be loaded */ 126 127 printf("start game here.\n"); 128 pause_and_quit(1); 129 } 130 131 132 al_flip_display(); 133 134 pf("flushing.\n"); 135 fflush(stdout); 136 137 } 138 139 140 141 game_log(MAIN_LOG, "End of program. Returning 0.\n"); 142 return 0; 143}

weapon_S
Member #7,859
October 2006
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William Labbett
Member #4,486
March 2004
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I changed a line to

CurrentMenu->DrawMenu(close_menu, al_get_timer_count(OneRunObject.timer));

It was

CurrentMenu->DrawMenu();

Also I started using the monolith file but I switched back to seperate archives to see if the monolith was the cause but it turned out it wasn't.

weapon_S
Member #7,859
October 2006
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You are sure it runs, except for the redraw? I.e. it closes immediately when you tell it too? If a lot of events stack up, it won't close immediately.

You changed the timing code? Maybe you forgot to register the timer event source.

BTW Is that a single-case switch-statement :o
"pf" pfff... ::)
Also, if you need a text file and a bunch of bmp's, you could use a single argument to identify them both... F.i. "normal_theme" (it will look in the 'normal_theme' directory) or "./mythemes/user1" (it will look for all files in that directory). Much easier theming.

Elias
Member #358
May 2000

Don't call al_flip_display() if you aren't drawing. It takes a long time but your current code only handles one event per al_flip_display call which inevitably leads to the queue never being empty.

Also, about formatting, don't use any tabs (or alternatively, only tabs, but that's bound to go wrong in some places) then line up { and } with spaces and use a constant indentation. The way you have it right now makes it very hard to read.

--
"Either help out or stop whining" - Evert

William Labbett
Member #4,486
March 2004
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weapon_S said:

"pf" pfff...

When you suffer from newb blues as badly as me, and you've typed printf() so many times, using function name macros like pf was one the things I've learned that been a relief.

Thanks both of you for the advice. I'm going to sort out that thing with the two strings. That'll make life a bit easier.

Also, thanks Elias. My program works lovely now.

Very grateful for the guidance.

/off to kettle for tea

weapon_S
Member #7,859
October 2006
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William Labbett
Member #4,486
March 2004
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it's the dreadful indentation that makes it look like that

bamccaig
Member #7,536
July 2006
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Elias said:

Also, about formatting, don't use any tabs (or alternatively, only tabs, but that's bound to go wrong in some places) then line up { and } with spaces and use a constant indentation. The way you have it right now makes it very hard to read.

^ This.

BAF
Member #2,981
December 2002
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Elias said:

Also, about formatting, don't use any tabs (or alternatively, only tabs, but that's bound to go wrong in some places) then line up { and } with spaces and use a constant indentation. The way you have it right now makes it very hard to read.

FFS, do NOT indent with spaces. That's what tabs are for, and they're infinitely more flexible.

If you need to line things up (like code that bleeds onto another line), tab it in to the same level, then use spaces.

Edgar Reynaldo
Member #8,592
May 2007
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bamccaig
Member #7,536
July 2006
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BAF said:

If you need to line things up (like code that bleeds onto another line), tab it in to the same level, then use spaces.

That is fine in theory, but in practice it's very difficult to maintain. It's easy for you, or somebody else on the team, to mix up the tabs or spaces accidentally. Being whitespace, you won't notice. Using spaces is just much easier, especially with a mediocre or better editor that can expand them automatically for you. There's never guess work. It just works.

There's absolutely no practical difference for me. I hit the tab key (or >>) to indent, the shift-tab combo (or <<) to un-indent, and there's no visible difference. As for the actual indentation step size, you can pretty easily write a program (or editor extension or whatever) to automatically convert between them if you care, but 4-spaces should be a happy medium for everybody.

BAF
Member #2,981
December 2002
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Quote:

As for the actual indentation step size, you can pretty easily write a program (or editor extension or whatever) to automatically convert between them if you care, but 4-spaces should be a happy medium for everybody.

Or you can, you know, just use tabs and configure your editor to have how many ever spaces you want.

I don't understand why people think spaces are for indentation, and then come up with all these crazy workarounds to make it sound so usable.

bamccaig
Member #7,536
July 2006
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Don't knock it until you've tried it. It's clear that you haven't. At least, not with a useful editor (hint: Visual Studio's editor is not useful).

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