Example application using the mixer API

examples/mixer.py

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+"""Example for using the mixer API.
+
+Plays music in the background and plays a coin sound when the user hits the
+space bar.
+"""
+
+import sdl2
+import sdl2.ext
+import sdl2.sdlmixer as mix
+
+
+SAMPLE_RATE = 44100
+CHUNK_SIZE = 4096
+
+def run():
+    # Setup--initialize the video subsystem and start a window
+    sdl2.ext.init()
+    window = sdl2.ext.Window("Let's play sound", size=(800, 600))
+    window.show()
+
+    # Dynamically load libraries needed by the mixer.
+    if mix.Mix_Init(0) == -1:
+        print('ERR: Mix_Init')
+        exit()
+
+    # Initialize the mixer API. Use 2 channels (stereo).
+    if mix.Mix_OpenAudio(SAMPLE_RATE, mix.MIX_DEFAULT_FORMAT, 2, CHUNK_SIZE) == -1:
+        print('ERR: Mix_OpenAudio')
+        exit()
+
+    # This call won't fail.
+    mix.Mix_AllocateChannels(1)
+
+    # Set volume of the channel to max. We only allocated 1 channel, so use 0.
+    mix.Mix_Volume(0, mix.MIX_MAX_VOLUME)
+
+    # Load sound assets
+    music = mix.Mix_LoadMUS(b'resources/title_screen.wav')
+    if not music:
+        print('ERR: Failed to load music')
+        exit()
+
+    coin_sound = mix.Mix_LoadWAV(b'resources/handleCoins.ogg')
+    if not coin_sound:
+        print('ERR: Failed to load sound effects')
+        exit()
+
+    # Start playing music and loop forever
+    if mix.Mix_PlayMusic(music, -1) == -1:
+        print('WARN: Mix_PlayMusic')
+
+    running = True
+    while running:
+        for event in sdl2.ext.get_events():
+            if event.type == sdl2.SDL_QUIT:
+                running = False
+                break
+            if event.type == sdl2.SDL_KEYDOWN:
+                if event.key.keysym.sym == sdl2.SDLK_SPACE:
+                    # When the user hits SPACE, play the coin sound
+                    mix.Mix_PlayChannel(0, coin_sound, 0)
+
+        sdl2.SDL_Delay(10)
+
+    # Clean up
+    mix.Mix_HaltMusic(music)
+    mix.Mix_FreeMusic(music)
+    if mix.Mix_Playing(0):
+        mix.Mix_HaltChannel(0)
+    mix.Mix_FreeChunk(coin_sound)
+
+    mix.Mix_CloseAudio()
+
+if __name__ == '__main__':
+    run()

examples/resources/credits.txt

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+
+title_screen.wav: CC0 by Juhani Junkala
+handleCoins.ogg: CC0 by Kenney (www.kenney.nl)