OpenTTD Source: src/sound/sdl_s.cpp Source File

OpenTTD Source 15.0-beta1

sdl_s.cpp
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1/*
2 * This file is part of OpenTTD.
3 * OpenTTD 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, version 2.
4 * OpenTTD 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.
5 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
6 */
7
10#ifdef WITH_SDL
11
12#include "../stdafx.h"
13
14#include "../mixer.h"
15#include "sdl_s.h"
16#include <SDL.h>
17
18#include "../safeguards.h"
19
21 static FSoundDriver_SDL iFSoundDriver_SDL;
22
28 static void CDECL fill_sound_buffer(void *, Uint8 *stream, int len)
29{
30 MxMixSamples(stream, len / 4);
31}
32
33std::optional<std::string_view> SoundDriver_SDL::Start(const StringList &parm)
34{
35 SDL_AudioSpec spec;
36
37 /* Only initialise SDL if the video driver hasn't done it already */
38 int ret_code = 0;
39 if (SDL_WasInit(SDL_INIT_EVERYTHING) == 0) {
40 ret_code = SDL_Init(SDL_INIT_AUDIO | SDL_INIT_NOPARACHUTE);
41 } else if (SDL_WasInit(SDL_INIT_AUDIO) == 0) {
42 ret_code = SDL_InitSubSystem(SDL_INIT_AUDIO);
43 }
44 if (ret_code == -1) return SDL_GetError();
45
46 spec.freq = GetDriverParamInt(parm, "hz", 44100);
47 spec.format = AUDIO_S16SYS;
48 spec.channels = 2;
49 spec.samples = GetDriverParamInt(parm, "samples", 1024);
50 spec.callback = fill_sound_buffer;
51 MxInitialize(spec.freq);
52 SDL_OpenAudio(&spec, &spec);
53 SDL_PauseAudio(0);
54 return std::nullopt;
55}
56
57 void SoundDriver_SDL::Stop()
58{
59 SDL_CloseAudio();
60 SDL_QuitSubSystem(SDL_INIT_AUDIO);
61 if (SDL_WasInit(SDL_INIT_EVERYTHING) == 0) {
62 SDL_Quit(); // If there's nothing left, quit SDL
63 }
64}
65
66#endif /* WITH_SDL */
FSoundDriver_SDL
Factory for the SDL sound driver.
Definition sdl_s.h:25
SoundDriver_SDL::Start
std::optional< std::string_view > Start(const StringList &param) override
Start this driver.
Definition sdl_s.cpp:33
SoundDriver_SDL::Stop
void Stop() override
Stop this driver.
Definition sdl_s.cpp:57
GetDriverParamInt
int GetDriverParamInt(const StringList &parm, const char *name, int def)
Get an integer parameter the list of parameters.
Definition driver.cpp:76
iFSoundDriver_SDL
static FSoundDriver_SDL iFSoundDriver_SDL
Factory for the SDL sound driver.
Definition sdl_s.cpp:21
fill_sound_buffer
static void CDECL fill_sound_buffer(void *, Uint8 *stream, int len)
Callback that fills the sound buffer.
Definition sdl_s.cpp:28
sdl_s.h
Base for playing sound via SDL.
StringList
std::vector< std::string > StringList
Type for a list of strings.
Definition string_type.h:60