Hey guys... I noticed some weird CPU usage while developing a project using an opengl window in allegro 5.0.5
Basically, the program was using ~15% cpu time (a core on some 60% usage since both machines I tested were quad-cores)
I removed all calls to the rest of my program and compiled this source code:
#SelectExpand
1#include <iostream>
2#include <allegro5/allegro.h>
3#include <memory>
4//#include "Game.h"
5#include <allegro5/allegro_primitives.h>
6#include <allegro5/allegro_font.h>
7#include <allegro5/allegro_ttf.h>
8#include <allegro5/allegro_image.h>
9
10const int FPS
= 60;
11
12bool initializeAllegro
(ALLEGRO_DISPLAY*& display,
ALLEGRO_EVENT_QUEUE*& queue,
ALLEGRO_TIMER*& timer
) {
13 if (!al_init()) return false;
14 if(!al_init_image_addon()) {
15 std::cout
<< "Error initializing image addon!\n";
16 return false;
17 }
18 if (!al_install_keyboard()){
19 std::cout
<< "Error installing keyboard!\n";
20 return false;
21 }
22 if (!al_install_mouse()){
23 std::cout
<< "Error installing mouse!\n";
24 return false;
25 }
26 al_set_new_display_flags(ALLEGRO_OPENGL
);
27 //display = al_create_display(Game::WIDTH, Game::HEIGHT);
28 display
= al_create_display(800,
800);
29 if (!display
){
30 std::cout
<< "Error creating display!\n";
31 return false;
32 }
33 al_init_font_addon();
34 if (!al_init_ttf_addon()){
35 std::cout
<< "Error initializing TTF!\n";
36 return false;
37 }
38 if (!al_init_primitives_addon()){
39 std::cout
<< "Error initializing primitives!\n";
40 return false;
41 }
42 queue
= al_create_event_queue();
43 if (!queue
){
44 std::cout
<< "Error creating queue!\n";
45 return false;
46 }
47 al_register_event_source(queue,
al_get_display_event_source(display
));
48 al_register_event_source(queue,
al_get_keyboard_event_source());
49// if (al_hide_mouse_cursor(display) && al_grab_mouse(display)) {
50// al_register_event_source(queue, al_get_mouse_event_source());
51// } else al_show_mouse_cursor(display);
52 timer
= al_create_timer(1.
0/FPS
);
53 if (!timer
) {
54 std::cout
<< "Error creating timer!\n";
55 return false;
56 }
57 al_start_timer(timer
);
58 al_register_event_source(queue,
al_get_timer_event_source(timer
));
59 {
60 ALLEGRO_PATH
* p
= al_get_standard_path(ALLEGRO_RESOURCES_PATH
);
61 al_set_path_filename(p,
"");
62 al_append_path_component(p,
"data");
63 al_make_path_canonical(p
);
64// std::cout << al_path_cstr(p, '/');
65 al_change_directory(al_path_cstr(p,
'/'));
66 al_destroy_path(p
);
67 }
68 return true;
69}
70
71int main
(){
72 ALLEGRO_DISPLAY* display
= nullptr
;
73 ALLEGRO_EVENT_QUEUE* queue
= nullptr
;
74 ALLEGRO_TIMER* timer
= nullptr
;
75 if (!initializeAllegro
(display, queue, timer
)){
76 std::cout
<< "Error during allegro initialization!\n";
77 al_rest(10);
78 return 1;
79 }
80// auto game = std::make_shared<Game>();
81 bool cont
= true;
82 bool redraw
= true;
83 while (cont
84 //&& !game->isOver()
85 ){
86 ALLEGRO_EVENT ev
;
87 al_wait_for_event(queue,
&ev
);
88 const ALLEGRO_EVENT_TYPE type
= ev.type
;
89 switch(type
){
90 case ALLEGRO_EVENT_DISPLAY_CLOSE:
91 cont
= false;
92 break;
93 case ALLEGRO_EVENT_TIMER:
94 //game->step();
95 redraw
= true;
96 break;
97 case ALLEGRO_EVENT_MOUSE_AXES:
98// al_set_mouse_xy(display, Game::WIDTH/2.0f, Game::HEIGHT/2.0f);
99 default:
100 //game->onEvent(ev);
101 break;
102 }
103 if (redraw
&& al_event_queue_is_empty
(queue
)){
104 redraw
= false;
105 //game->draw();
106 al_flip_display();
107 }
108 }
109
110 al_destroy_event_queue(queue
);
111 al_destroy_timer(timer
);
112 al_uninstall_keyboard();
113 al_uninstall_mouse();
114 al_destroy_display(display
);
115 return 0;
116}
windows binary: http://www.allegro.cc/files/attachment/605652
allegro dll for convenience: http://www.allegro.cc/files/attachment/605653
Still uses ~15% cpu on both machines I tested (both quad-cores, one with a GeForce 9800 GTX and one with a 430). Tried updating the graphics drivers on the 430 and running the program for about 20 minutes, but nothing changed.
Either commenting out al_flip_display(); (line 106) or al_set_new_display_flags(ALLEGRO_OPENGL); (line 26) made cpu usage plummet down to 0%
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