我一直在做这个平台化的 Allegro 5 测试，稍后我将把它变成一个游戏。到目前为止，Allegro 的每个附加组件都运行良好，当时我尝试使用音频播放我在 Audacity 中制作的 .ogg 文件。我正在使用 MinGW 版本，并将所有内容与 Code::Blocks 静态链接。它只有一个文件 main.cpp：
#include <stdio.h> // Good library to always have on hand
#include <math.h> // C++ math library
#include <allegro5/allegro.h> // Allegro base library
#include <allegro5/allegro_audio.h> // Allegro audio library
#include <allegro5/allegro_acodec.h> // Library used to load different audio codecs
#include <allegro5/allegro_image.h> // You MUST load the image library for anything bitmap-image related
#include <allegro5/allegro_primitives.h> // Allegro primitives addon, for drawing shapes n' stuff
#include <allegro5/allegro_native_dialog.h> // You load this for the native message box feature (see below)
enum MYKEYS {
KEY_UP, KEY_DOWN, KEY_LEFT, KEY_RIGHT
};
int main() {
ALLEGRO_DISPLAY *display = NULL;
ALLEGRO_DISPLAY_MODE disp_info;
ALLEGRO_SAMPLE *sound_effect = NULL;
ALLEGRO_BITMAP *manLeft = NULL; // Maximum texture size is a minimum of 1024 * 1024
ALLEGRO_EVENT_QUEUE *event_queue = NULL;
ALLEGRO_TIMER *fpsTimer = NULL;
const float FPS = 60; // This global variable "FPS" is how many times per second the screen will redraw
const char window_title[] = "Neil's Box Game"; // This is the window's title
int window_width = 800; // This is the display's in-window width
int window_height = 600; // This is the display's in-window height
int display_width = window_width;
int display_height = window_height;
bool redraw = true;
bool doexit = false;
bool manFlipped = false;
bool prevUp = false;
bool isFullscreen = false;
int manWidth = 19; // The "man" sprite's pixel width
int manHeight = 48; // The "man" sprite's pixel height
int manX = (display_width / 2) - (manWidth / 2); // This is the man's drawn x-value
int manY = display_height - manHeight; // Same for y
float manXVel = 0.0; // For our "platformer", this is the player character's x-axis velocity
float manXVelCap = 200.0 / FPS; // This "caps" the x-velocity to how much we want our character to move, 200 is how much in 1 second
float manYVel = 0.0; // Etc. for y
float manYVelCap = 400.0 / FPS; // Etc.
bool key[4] = { false, false, false, false };
if(!al_init()) { // Initialise Allegro, test it's working
fprintf(stderr, "ERROR: Failed to initialize Allegro library!\n");
return -1;
}
if(!al_install_audio()){
fprintf(stderr, "ERROR: Failed to initialize Allegro audio add-on!\n");
return -1;
}
if(!al_init_acodec_addon()){
fprintf(stderr, "ERROR: Failed to initialize Allegro audio codecs!\n");
return -1;
}
if(!al_install_keyboard()) { // Initialises the keyboard control, test if it's working
fprintf(stderr, "ERROR: Failed to initialize the keyboard!\n");
return -1;
}
if(!al_init_image_addon()) { // Initialise Allegro's image addon, make sure it works
fprintf(stderr, "ERROR: Failed to initialize Allegro's image add-on!\n");
return -1;
}
if (!al_init_primitives_addon()) { // Initialise the Allegro primitives addon
fprintf(stderr, "ERROR: Failed to initialize Allegro's primitives add-on!\n");
return -1;
}
// "al_reserve_samples" sets how many audio samples you can load
if (!al_reserve_samples(1)){
fprintf(stderr, "ERROR: Failed to reserve Allegro audio samples!\n");
return -1;
}
fpsTimer = al_create_timer(1.0 / FPS); // Create our FPS timer, and make sure it's working
if(!fpsTimer) {
fprintf(stderr, "ERROR: Failed to create timer!\n");
return -1;
}
sound_effect = al_load_sample("pitchshift.ogg");
if (!sound_effect){
fprintf(stderr, "ERROR: Audio sample \"pitchshift.ogg\" not loaded!\n" );
return -1;
}
al_get_display_mode(al_get_num_display_modes() - 1, &disp_info);
display = al_create_display(display_width, display_height);
if(!display) {
al_show_native_message_box(display, "Error", "Error", "Failed to create display!", NULL, ALLEGRO_MESSAGEBOX_ERROR);
return -1;
}
// Set it to the efficient blender mode
al_set_blender(ALLEGRO_ADD, ALLEGRO_ALPHA, ALLEGRO_INVERSE_ALPHA);
// This loads the event queue, and verifies it's working
event_queue = al_create_event_queue();
if(!event_queue) {
al_show_native_message_box(display, "Error", "Error", "Failed to create event queue!", NULL, ALLEGRO_MESSAGEBOX_ERROR);
al_destroy_display(display); // If failed, always destroy EVERYTHING that has been allegro-created, like displays and timers
al_destroy_timer(fpsTimer);
return -1;
}
// Always load images AFTER the creation of the display
manLeft = al_load_bitmap("Left.png"); // Load our man png
if(!manLeft) { // Check to make sure if it loaded right, if not say "!@#$ THIS" and gtfo
al_show_native_message_box(display, "Error", "Error", "Failed to load image!", NULL, ALLEGRO_MESSAGEBOX_ERROR);
al_destroy_display(display);
al_destroy_timer(fpsTimer);
return 0;
}
al_set_window_title(display, window_title); // Sets the window's caption title
al_register_event_source(event_queue, al_get_display_event_source(display)); // This attaches the event_queue to the "display" display iten
al_register_event_source(event_queue, al_get_timer_event_source(fpsTimer)); // Bind the fpsTimer object to the event handler
al_register_event_source(event_queue, al_get_keyboard_event_source()); // Bind the keyboard to the Allegro event handler
al_clear_to_color(al_map_rgb(255,255,255)); // Setting the mood...
al_draw_bitmap(manLeft, manX, manY, 0); // Draw the "left" sprite, (imagename, x, y, FLAGS) FLAGS is either 0 for nothing, "ALLEGRO_FLIP_HORIZONTAL" or "ALLEGRO_FLIP_VERTICAL", purdy self explanatory
al_start_timer(fpsTimer); // After we've refreshed the display, begin the FPS timer
while (!doexit) {
ALLEGRO_EVENT ev;
al_wait_for_event(event_queue, &ev);
switch(ev.type) {
case ALLEGRO_EVENT_DISPLAY_CLOSE:
doexit = true;
break;
case ALLEGRO_EVENT_KEY_DOWN:
switch(ev.keyboard.keycode) {
case ALLEGRO_KEY_UP:
key[KEY_UP] = true;
break;
case ALLEGRO_KEY_DOWN:
key[KEY_DOWN] = true;
break;
case ALLEGRO_KEY_LEFT:
key[KEY_LEFT] = true;
break;
case ALLEGRO_KEY_RIGHT:
key[KEY_RIGHT] = true;
break;
case ALLEGRO_KEY_ESCAPE:
doexit = true;
case ALLEGRO_KEY_F11:
if (isFullscreen) {
manX *= ((float)window_width / (float)disp_info.width);
manY *= ((float)window_height / (float)disp_info.height);
al_set_new_display_flags(ALLEGRO_WINDOWED);
al_destroy_display(display);
display = al_create_display(window_width, window_height);
al_set_window_title(display, window_title);
al_register_event_source(event_queue, al_get_display_event_source(display)); // After re-creating the display, we need to again bind it to the event queue
display_width = window_width;
display_height = window_height;
isFullscreen = false;
} else {
manX *= ((float)disp_info.width / (float)window_width);
manY *= ((float)disp_info.height / (float)window_height);
al_set_new_display_flags(ALLEGRO_FULLSCREEN);
al_destroy_display(display);
display = al_create_display(disp_info.width, disp_info.height);
al_set_window_title(display, window_title);
al_register_event_source(event_queue, al_get_display_event_source(display)); // After re-creating the display, we need to again bind it to the event queue
display_width = disp_info.width;
display_height = disp_info.height;
isFullscreen = true;
}
}
break;
case ALLEGRO_EVENT_KEY_UP:
switch(ev.keyboard.keycode) {
case ALLEGRO_KEY_UP:
key[KEY_UP] = false;
break;
case ALLEGRO_KEY_DOWN:
key[KEY_DOWN] = false;
break;
case ALLEGRO_KEY_LEFT:
key[KEY_LEFT] = false;
break;
case ALLEGRO_KEY_RIGHT:
key[KEY_RIGHT] = false;
break;
case ALLEGRO_KEY_ESCAPE:
doexit = true;
break;
}
break;
case ALLEGRO_EVENT_TIMER:
if(key[KEY_UP] && !prevUp) {
if (manY >= display_height - manHeight) {
manYVel = -10.0;
al_play_sample(sound_effect, 1.0, 0.0, 1.0, ALLEGRO_PLAYMODE_ONCE, NULL);
}
}
if(key[KEY_LEFT]) {
manXVel -= 0.5;
manFlipped = false; // Change the sprite
}
if(key[KEY_RIGHT]) {
manXVel += 0.5;
manFlipped = true; // Change the sprite
}
// Cap the velocity to make sure he doesn't get moving TOO fast...
if (manXVel > manXVelCap) {
manXVel = manXVelCap;
}
if (manXVel < -manXVelCap) {
manXVel = -manXVelCap;
}
if (manYVel > manYVelCap) {
manYVel = manYVelCap;
}
if (manYVel < -manYVelCap) {
manYVel = -manYVelCap;
}
if (manXVel * FPS > -5.0 && manXVel * FPS < 5.0) {
manXVel = 0;
}
// Add some horizontal ground friction
if ((!key[KEY_LEFT] || !key[KEY_RIGHT]) && manY >= display_height - manHeight) { // Make sure that he's "sliding" and he's touching the ground
manXVel *= pow(10, log (0.4) / FPS); // The 0.4 is how much x friction we want every second
}
// Adding gravity
manYVel += 0.15;
redraw = true;
prevUp = key[KEY_UP];
break;
default:
break;
}
if(redraw && al_is_event_queue_empty(event_queue)) {
if (manX > display_width - manWidth) {
manX = display_width - manWidth;
}
if (manX < 0) {
manX = 0;
}
if (manY > display_height - manHeight) {
manY = display_height - manHeight;
}
if (manY < 0) {
manY = 0;
}
al_clear_to_color(al_map_rgb(255,255,255)); // Clear screen
if (manFlipped) {
al_draw_bitmap(manLeft, (int)manX, (int)manY, ALLEGRO_FLIP_HORIZONTAL); // Draw our "man sprite"
} else {
al_draw_bitmap(manLeft, (int)manX, (int)manY, 0); // Draw our "man sprite"
}
al_flip_display(); // Refresh screen
// Put the x and y refreshes AFTER the screen update to preserve collision checking is working
redraw = false;
manX += manXVel; // Assign the respective velocities to their axes
manY += manYVel; // Same for y
}
}
// ON CLOSURE OF THE PROGRAM, YOU MUST DESTROY EVERYTHING THAT IS ALLEGRO CREATED, IN THE FOLLOWING ORDER:
// - Bitmaps
// - Timers
// - Displays
// - Event queues
al_destroy_bitmap(manLeft); // Destroy the bimaps
al_destroy_timer(fpsTimer); // Destroy the timer
al_destroy_display(display); // Delete the display
al_destroy_event_queue(event_queue); // You have to destroy an event queue after you've created it
return 0; // nitey nite
}
当我尝试构建我的代码时，它给了我这个奇怪的错误序列，我在 Google 上没有找到任何解决方案：
||=== box - Allegro Visual Thingy, Default ===|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourcei'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetSourcei'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetSourcei'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteBuffers'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteSources'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourceStop'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteSources'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteBuffers'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGenSources'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGenBuffers'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourcef'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourcePlay'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteSources'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteSources'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteBuffers'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteSources'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGenSources'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGenBuffers'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alBufferData'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourcei'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourcei'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourcef'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteSources'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteSources'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteBuffers'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alDeleteSources'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourcei'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alBufferData'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourceQueueBuffers'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourcePlay'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetSourcei'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourceUnqueueBuffers'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alBufferData'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourceQueueBuffers'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetSourcei'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourcePlay'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alSourceStop'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alGetError'|
C:\Allegro\allegro-5.0.7-mingw-4.6.2\lib\liballegro_audio-5.0.7-static-mt.a(openal.o):openal.c|| undefined reference to `alcGetError'|
||More errors follow but not being shown.|
||Edit the max errors limit in compiler options...|
||=== Build finished: 50 errors, 0 warnings ===|
我将发布Code::Blocks 项目，以便您可以看到我正在链接的内容，但我只是不明白为什么音频库是唯一不起作用的东西！
感谢您的帮助，
-尼尔