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Diffstat (limited to 'sdl2/mixer.scm')
| -rw-r--r-- | sdl2/mixer.scm | 319 |
1 files changed, 319 insertions, 0 deletions
diff --git a/sdl2/mixer.scm b/sdl2/mixer.scm new file mode 100644 index 0000000..c740d85 --- /dev/null +++ b/sdl2/mixer.scm @@ -0,0 +1,319 @@ +;;; guile-sdl2 --- FFI bindings for SDL2 +;;; Copyright © 2015 David Thompson <davet@gnu.org> +;;; +;;; This file is part of guile-sdl2. +;;; +;;; Guile-sdl2 is free software; you can redistribute it and/or modify +;;; it under the terms of the GNU Lesser General Public License as +;;; published by the Free Software Foundation; either version 3 of the +;;; License, or (at your option) any later version. +;;; +;;; Guile-sdl2 is distributed in the hope that it will be useful, but +;;; WITHOUT ANY WARRANTY; without even the implied warranty of +;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +;;; General Public License for more details. +;;; +;;; You should have received a copy of the GNU Lesser General Public +;;; License along with guile-sdl2. If not, see +;;; <http://www.gnu.org/licenses/>. + +;;; Commentary: +;; +;; Font rendering. +;; +;;; Code: + +(define-module (sdl2 mixer) + #:use-module (ice-9 format) + #:use-module (ice-9 match) + #:use-module (system foreign) + #:use-module (sdl2) + #:use-module ((sdl2 bindings) #:prefix ffi:) + #:use-module ((sdl2 bindings mixer) #:prefix ffi:) + #:export (%default-frequency + %default-format + %default-chunk-size + + mixer-init + mixer-quit + open-audio + close-audio + + chunk? + load-chunk + delete-chunk! + set-chunk-volume! + play-chunk! + + set-channel-volume! + pause-channel! + resume-channel! + stop-channel! + channel-playing? + playing-channels-count + channel-paused? + paused-channels-count + + music? + load-music + delete-music! + play-music! + set-music-volume! + music-volume + pause-music! + resume-music! + rewind-music! + stop-music! + music-playing? + music-paused?)) + +(define (audio-format->symbol n) + (cond + ((= n ffi:AUDIO_U8) 'u8) + ((= n ffi:AUDIO_S8) 's8) + ((= n ffi:AUDIO_U16LSB) 'u16lsb) + ((= n ffi:AUDIO_S16LSB) 's16lsb) + ((= n ffi:AUDIO_U16MSB) 'u16msb) + ((= n ffi:AUDIO_S16MSB) 's16msb) + ((= n ffi:AUDIO_U16) 'u16) + ((= n ffi:AUDIO_S16) 's16) + ((= n ffi:AUDIO_S32LSB) 's32lsb) + ((= n ffi:AUDIO_S32MSB) 's32msb) + ((= n ffi:AUDIO_S32) 's32) + ((= n ffi:AUDIO_F32LSB) 'f32lsb) + ((= n ffi:AUDIO_F32MSB) 'f32msb) + ((= n ffi:AUDIO_F32) 'f32))) + +(define symbol->audio-format + (match-lambda + ('u8 ffi:AUDIO_U8) + ('s8 ffi:AUDIO_S8) + ('u16lsb ffi:AUDIO_U16LSB) + ('s16lsb ffi:AUDIO_S16LSB) + ('u16msb ffi:AUDIO_U16MSB) + ('s16msb ffi:AUDIO_S16MSB) + ('u16 ffi:AUDIO_U16) + ('s16 ffi:AUDIO_S16) + ('s32lsb ffi:AUDIO_S32LSB) + ('s32msb ffi:AUDIO_S32MSB) + ('s32 ffi:AUDIO_S32) + ('f32lsb ffi:AUDIO_F32LSB) + ('f32msb ffi:AUDIO_F32MSB) + ('f32 ffi:AUDIO_F32))) + +(define %default-frequency ffi:MIX_DEFAULT_FREQUENCY) +(define %default-format (audio-format->symbol ffi:MIX_DEFAULT_FORMAT)) +(define %default-chunk-size 4096) + +(define* (mixer-init #:optional + (formats '(flac mod modplug mp3 ogg fluidsynth))) + "Initialize mixer library with support for FORMATS, a list of +symbols representing audio file formats. Possible formats are: + +- flac +- mod +- modplug +- mp3 +- ogg +- fluidsynth" + (define symbol->init-flag + (match-lambda + ('flac ffi:MIX_INIT_FLAC) + ('mod ffi:MIX_INIT_MOD) + ('modplug ffi:MIX_INIT_MODPLUG) + ('mp3 ffi:MIX_INIT_MP3) + ('ogg ffi:MIX_INIT_OGG) + ('fluidsynth ffi:MIX_INIT_FLUIDSYNTH))) + + (let* ((mask (apply logior (map symbol->init-flag formats))) + (result (ffi:mix-init mask))) + (unless (= mask result) + (sdl-error "mixer-init" "failed to initialize mixer library")))) + +(define (mixer-quit) + "Shutdown mixer library." + (ffi:mix-quit)) + +(define* (open-audio #:key (frequency %default-frequency) + (format %default-format) + (stereo? #t) + (chunk-size %default-chunk-size)) + "Initialize the mixer API. FREQUENCY specificies the sample rate in +hertz. When STEREO? is #t, two output channels are used, otherwise +mono output is used instead. CHUNK-SIZE specifies the number of bytes +used per output sample. FORMAT is a symbol that specifies the output +sample format. Possible values are: + +- u8 +- s8 +- u16lsb +- s16lsb +- u16msb +- s16msb +- u16 +- s16 +- s32lsb +- s32msb +- s32 +- f32lsb +- f32msb +- f32" + (unless (zero? (ffi:mix-open-audio frequency + (symbol->audio-format format) + (if stereo? 2 1) + chunk-size)) + (sdl-error "open-audio" "failed to open audio"))) + +(define (close-audio) + "Shut down the mixer API." + (ffi:mix-close-audio)) + + +;;; +;;; Chunks +;;; + +(define-wrapped-pointer-type <chunk> + chunk? + wrap-chunk unwrap-chunk + (lambda (chunk port) + (format port "#<chunk ~x>" + (pointer-address (unwrap-chunk chunk))))) + +(define (load-chunk file) + "Load the audio data in FILE and return an audio chunk." + (let ((ptr (ffi:mix-load-wav-rw (ffi:sdl-rw-from-file (string->pointer file) + (string->pointer "rb")) + 1))) + (if (null-pointer? ptr) + (sdl-error "load-audio" "failed to load audio") + (wrap-chunk ptr)))) + +(define (delete-chunk! chunk) + "Free the memory used for CHUNK." + (ffi:mix-free-chunk (unwrap-chunk chunk))) + +(define (set-chunk-volume! chunk volume) + "Set the loudness of CHUNK to VOLUME, an integer in the range [0, +128]. Return the previous chunk volume setting." + (ffi:mix-volume-chunk (unwrap-chunk chunk) volume)) + +(define* (play-chunk! chunk #:key (loops 0) channel) + "Play CHUNK on CHANNEL, an integer channel identifier or #f to use +the first unreserved audio channel. CHUNK will play LOOPS + 1 times. +Return the channel identifier that CHUNK is played on." + (let ((ret (ffi:mix-play-channel-timed (if channel channel -1) + (unwrap-chunk chunk) + loops -1))) + (if (= -1 ret) + (sdl-error "play-chunk!" "failed to play audio") + ret))) + + +;;; +;;; Channels +;;; + +(define (set-channel-volume! channel volume) + "Set the loudness of CHANNEL, an integer channel identifier or #f +for all channels, to VOLUME, an integer in the range 0-128. Return +the previous volume of CHANNEL, or the average of all channels if +CHANNEL is #f." + (ffi:mix-volume (if channel channel -1) volume)) + +(define (pause-channel! channel) + "Pause playback on CHANNEL, an integer channel identifier, or #f to +pause all channels." + (ffi:mix-pause (if channel channel -1))) + +(define (resume-channel! channel) + "Resume playback on CHANNEL, an integer channel identifier, or #f to +pause all channels." + (ffi:mix-resume (if channel channel -1))) + +(define (stop-channel! channel) + "Halt playback on CHANNEL, an integer channel identifier, or #f to +pause all channels." + (ffi:mix-halt-channel (if channel channel -1))) + +(define (channel-playing? channel) + "Return #t if CHANNEL is playing." + (= 1 (ffi:mix-playing channel))) + +(define (playing-channels-count) + "Return the number of channels currently playing." + (ffi:mix-playing -1)) + +(define (channel-paused? channel) + "Return #t if CHANNEL is paused." + (= 1 (ffi:mix-paused channel))) + +(define (paused-channels-count) + "Return the number of channels that are paused." + (ffi:mix-paused -1)) + + +;;; +;;; Music +;;; + +(define-wrapped-pointer-type <music> + music? + wrap-music unwrap-music + (lambda (music port) + (format port "#<music ~x>" + (pointer-address (unwrap-music music))))) + +(define (load-music file) + "Load music from FILE." + (let ((ptr (ffi:mix-load-mus (string->pointer file)))) + (if (null-pointer? ptr) + (sdl-error "load-music" "failed to load music") + (wrap-music ptr)))) + +(define (delete-music! music) + "Delete the memory used for MUSIC." + (ffi:mix-free-music (unwrap-music music))) + +(define* (play-music! music #:optional (loops 1)) + "Play MUSIC, repeated LOOPS times. LOOPS may be #f, in which case +the music loops indefinitely." + (unless (zero? (ffi:mix-play-music (unwrap-music music) (if loops loops -1))) + (sdl-error "play-music!" "failed to play music"))) + +(define (set-music-volume! volume) + "Set music loudness to VOLUME, an integer in the range 0-128. +Return the previous volume." + (if (>= volume 0) + (ffi:mix-volume-music volume) + (throw 'sdl-error "set-music-volume!" + "volume must be a non-negative integer"))) + +(define (music-volume) + "Return the music volume." + (ffi:mix-volume-music -1)) + +(define (pause-music!) + "Pause the music." + (ffi:mix-pause-music)) + +(define (resume-music!) + "Resume music playback." + (ffi:mix-resume-music)) + +(define (rewind-music!) + "Start music playback from the beginning. Rewinding is only +supported for MOD, OGG, MP3, and native MIDI music." + (ffi:mix-rewind-music)) + +(define (stop-music!) + "Halt music playback." + (ffi:mix-halt-music)) + +(define (music-playing?) + "Return #t if music is currently playing." + (= 1 (ffi:mix-playing-music))) + +(define (music-paused?) + "Return #t if music is currently paused." + (= 1 (ffi:mix-paused-music))) |