forked from 0ad/0ad
134 lines
5.1 KiB
C
Executable File
134 lines
5.1 KiB
C
Executable File
// OpenAL sound engine
|
|
//
|
|
// Copyright (c) 2004 Jan Wassenberg
|
|
//
|
|
// This program is free software; you can redistribute it and/or
|
|
// modify it under the terms of the GNU General Public License as
|
|
// published by the Free Software Foundation; either version 2 of the
|
|
// License, or (at your option) any later version.
|
|
//
|
|
// This program 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.
|
|
//
|
|
// Contact info:
|
|
// Jan.Wassenberg@stud.uni-karlsruhe.de
|
|
// http://www.stud.uni-karlsruhe.de/~urkt/
|
|
|
|
#include "handle.h"
|
|
|
|
|
|
//
|
|
// device enumeration
|
|
//
|
|
|
|
// prepare to enumerate all device names (this resets the list returned by
|
|
// snd_dev_next). return 0 on success, otherwise -1 (only if the requisite
|
|
// OpenAL extension isn't available). on failure, a "cannot enum device"
|
|
// message should be presented to the user, and snd_dev_set need not be
|
|
// called; OpenAL will use its default device.
|
|
// may be called each time the device list is needed.
|
|
extern int snd_dev_prepare_enum();
|
|
|
|
// return the next device name, or 0 if all have been returned.
|
|
// do not call unless snd_dev_prepare_enum succeeded!
|
|
// not thread-safe! (static data from snd_dev_prepare_enum is used)
|
|
extern const char* snd_dev_next();
|
|
|
|
|
|
//
|
|
// sound system setup
|
|
//
|
|
|
|
// tell OpenAL to use the specified device (0 for default) in future.
|
|
// if OpenAL hasn't been initialized yet, we only remember the device
|
|
// name, which will be set when oal_init is later called; otherwise,
|
|
// OpenAL is reinitialized to use the desired device.
|
|
// (this is to speed up the common case of retrieving a device name from
|
|
// config files and setting it; OpenAL doesn't have to be loaded until
|
|
// sounds are actually played).
|
|
// return 0 to indicate success, or the status returned while initializing
|
|
// OpenAL.
|
|
extern int snd_dev_set(const char* alc_new_dev_name);
|
|
|
|
// set maximum number of voices to play simultaneously,
|
|
// to reduce mixing cost on low-end systems.
|
|
// return 0 on success, or 1 if limit was ignored
|
|
// (e.g. if higher than an implementation-defined limit anyway).
|
|
extern int snd_set_max_voices(uint cap);
|
|
|
|
// set amplitude modifier, which is effectively applied to all sounds.
|
|
// must be non-negative; 1 -> unattenuated, 0.5 -> -6 dB, 0 -> silence.
|
|
extern int snd_set_master_gain(float gain);
|
|
|
|
|
|
//
|
|
// sound instance
|
|
//
|
|
|
|
// open and return a handle to the sound specified by the
|
|
// definition file <def_fn> (it consists of filename and gain).
|
|
//
|
|
// is_stream (default false) forces the sound to be opened as a stream:
|
|
// opening is faster, it won't be kept in memory, but only one instance
|
|
// can be open at a time.
|
|
extern Handle snd_open_def(const char* def_fn, bool stream = false);
|
|
|
|
// open and return a handle to the sound <snd_fn>.
|
|
// gain is set to the default, and may be changed via snd_set_gain.
|
|
//
|
|
// is_stream (default false) forces the sound to be opened as a stream:
|
|
// opening is faster, it won't be kept in memory, but only one instance
|
|
// can be open at a time.
|
|
extern Handle snd_open(const char* snd_fn, bool stream = false);
|
|
|
|
// close the sound <hvs> and set hvs to 0. if it was playing,
|
|
// it will be stopped. sounds are closed automatically when done
|
|
// playing; this is provided for completeness only.
|
|
extern int snd_free(Handle& hs);
|
|
|
|
// request the sound <hs> be played. once done playing, the sound is
|
|
// automatically closed (allows fire-and-forget play code).
|
|
// if no hardware voice is available, this sound may not be played at all,
|
|
// or in the case of looped sounds, later.
|
|
// priority (min 0 .. max 1, default 0) indicates which sounds are
|
|
// considered more important; this is attenuated by distance to the
|
|
// listener (see snd_update)
|
|
extern int snd_play(Handle hs, float priority = 0.0f);
|
|
|
|
// change 3d position of the sound source.
|
|
// if relative (default false), (x,y,z) is treated as relative to the
|
|
// listener; otherwise, it is the position in world coordinates.
|
|
// may be called at any time.
|
|
extern int snd_set_pos(Handle hs, float x, float y, float z, bool relative = false);
|
|
|
|
// change gain (amplitude modifier) of the sound source.
|
|
// must be non-negative; 1 -> unattenuated, 0.5 -> -6 dB, 0 -> silence.
|
|
extern int snd_set_gain(Handle hs, float gain);
|
|
|
|
// enable/disable looping on the sound source.
|
|
// used to implement variable-length sounds (e.g. while building).
|
|
//
|
|
// notes:
|
|
// - looping sounds are not discarded if they cannot be played for lack of
|
|
// a hardware voice at the moment play was requested.
|
|
// - once looping is again disabled and the sound has reached its end,
|
|
// the sound instance is freed automatically (as if never looped).
|
|
extern int snd_set_loop(Handle hs, bool loop);
|
|
|
|
|
|
//
|
|
// sound engine
|
|
//
|
|
|
|
// perform housekeeping (e.g. streaming); call once a frame.
|
|
//
|
|
// additionally, if any parameter is non-NULL, we set the listener
|
|
// position, look direction, and up vector (in world coordinates).
|
|
extern int snd_update(const float* pos, const float* dir, const float* up);
|
|
|
|
// free all resources and shut down the sound system.
|
|
// call before h_mgr_shutdown.
|
|
extern void snd_shutdown();
|