From e55844274de9381e80e568b0162b07292b28f2ab Mon Sep 17 00:00:00 2001
From: Brick <[EMAIL REDACTED]>
Date: Thu, 31 Aug 2023 13:31:42 +0100
Subject: [PATCH] Added SDL_(Get|Set)AudioStreamSpeed
---
include/SDL3/SDL_audio.h | 35 +++++++++++++++++++++++++++++
src/audio/SDL_audiocvt.c | 37 +++++++++++++++++++++++++++++++
src/dynapi/SDL_dynapi.sym | 2 ++
src/dynapi/SDL_dynapi_overrides.h | 2 ++
src/dynapi/SDL_dynapi_procs.h | 2 ++
5 files changed, 78 insertions(+)
diff --git a/include/SDL3/SDL_audio.h b/include/SDL3/SDL_audio.h
index f7f96289652a..4886f86f97c9 100644
--- a/include/SDL3/SDL_audio.h
+++ b/include/SDL3/SDL_audio.h
@@ -703,11 +703,46 @@ extern DECLSPEC int SDLCALL SDL_GetAudioStreamFormat(SDL_AudioStream *stream,
* \sa SDL_PutAudioStreamData
* \sa SDL_GetAudioStreamData
* \sa SDL_GetAudioStreamAvailable
+ * \sa SDL_SetAudioStreamSpeed
*/
extern DECLSPEC int SDLCALL SDL_SetAudioStreamFormat(SDL_AudioStream *stream,
const SDL_AudioSpec *src_spec,
const SDL_AudioSpec *dst_spec);
+/**
+ * Get the playback speed of an audio stream.
+ *
+ * \param stream the SDL_AudioStream to query.
+ * \returns the playback speed of the stream, or 0.0 on error
+ *
+ * \threadsafety It is safe to call this function from any thread, as it holds
+ * a stream-specific mutex while running.
+ *
+ * \since This function is available since SDL 3.0.0.
+ *
+ * \sa SDL_SetAudioStreamSpeed
+ */
+extern DECLSPEC float SDLCALL SDL_GetAudioStreamSpeed(SDL_AudioStream *stream);
+
+/**
+ * Change the playback speed of an audio stream.
+ *
+ * \param stream The stream the speed is being changed
+ * \param speed The new speed. 1.0 is normal speed, 1.2 is 20% faster, etc.
+ * Must be between 0.01 and 100.
+ * \returns 0 on success, or -1 on error.
+ *
+ * \threadsafety It is safe to call this function from any thread, as it holds
+ * a stream-specific mutex while running.
+ *
+ * \since This function is available since SDL 3.0.0.
+ *
+ * \sa SDL_GetAudioStreamSpeed
+ * \sa SDL_SetAudioStreamFormat
+ */
+extern DECLSPEC int SDLCALL SDL_SetAudioStreamSpeed(SDL_AudioStream *stream,
+ float speed);
+
/**
* Add data to be converted/resampled to the stream.
*
diff --git a/src/audio/SDL_audiocvt.c b/src/audio/SDL_audiocvt.c
index 93ae439e307b..b04b5c15f068 100644
--- a/src/audio/SDL_audiocvt.c
+++ b/src/audio/SDL_audiocvt.c
@@ -1237,6 +1237,43 @@ int SDL_SetAudioStreamFormat(SDL_AudioStream *stream, const SDL_AudioSpec *src_s
return 0;
}
+float SDL_GetAudioStreamSpeed(SDL_AudioStream *stream)
+{
+ if (!stream) {
+ SDL_InvalidParamError("stream");
+ return 0.0f;
+ }
+
+ SDL_LockMutex(stream->lock);
+ float speed = stream->speed;
+ SDL_UnlockMutex(stream->lock);
+
+ return speed;
+}
+
+int SDL_SetAudioStreamSpeed(SDL_AudioStream *stream, float speed)
+{
+ if (!stream) {
+ return SDL_InvalidParamError("stream");
+ }
+
+ // Picked mostly arbitrarily.
+ static const float min_speed = 0.01f;
+ static const float max_speed = 100.0f;
+
+ if (speed < min_speed) {
+ return SDL_SetError("Speed is too low");
+ } else if (speed > max_speed) {
+ return SDL_SetError("Speed is too high");
+ }
+
+ SDL_LockMutex(stream->lock);
+ stream->speed = speed;
+ SDL_UnlockMutex(stream->lock);
+
+ return 0;
+}
+
static int CheckAudioStreamIsFullySetup(SDL_AudioStream *stream)
{
if (stream->src_spec.format == 0) {
diff --git a/src/dynapi/SDL_dynapi.sym b/src/dynapi/SDL_dynapi.sym
index 0887e4ba36e1..dec025772085 100644
--- a/src/dynapi/SDL_dynapi.sym
+++ b/src/dynapi/SDL_dynapi.sym
@@ -902,6 +902,8 @@ SDL3_0.0.0 {
SDL_WriteS64BE;
SDL_GDKGetDefaultUser;
SDL_SetWindowFocusable;
+ SDL_GetAudioStreamSpeed;
+ SDL_SetAudioStreamSpeed;
# extra symbols go here (don't modify this line)
local: *;
};
diff --git a/src/dynapi/SDL_dynapi_overrides.h b/src/dynapi/SDL_dynapi_overrides.h
index 93d5db6b85df..faa73153a782 100644
--- a/src/dynapi/SDL_dynapi_overrides.h
+++ b/src/dynapi/SDL_dynapi_overrides.h
@@ -927,3 +927,5 @@
#define SDL_WriteS64BE SDL_WriteS64BE_REAL
#define SDL_GDKGetDefaultUser SDL_GDKGetDefaultUser_REAL
#define SDL_SetWindowFocusable SDL_SetWindowFocusable_REAL
+#define SDL_GetAudioStreamSpeed SDL_GetAudioStreamSpeed_REAL
+#define SDL_SetAudioStreamSpeed SDL_SetAudioStreamSpeed_REAL
diff --git a/src/dynapi/SDL_dynapi_procs.h b/src/dynapi/SDL_dynapi_procs.h
index 61bf6a26ce62..d0778b87ee39 100644
--- a/src/dynapi/SDL_dynapi_procs.h
+++ b/src/dynapi/SDL_dynapi_procs.h
@@ -973,3 +973,5 @@ SDL_DYNAPI_PROC(SDL_bool,SDL_WriteS64BE,(SDL_RWops *a, Sint64 b),(a,b),return)
SDL_DYNAPI_PROC(int,SDL_GDKGetDefaultUser,(XUserHandle *a),(a),return)
#endif
SDL_DYNAPI_PROC(int,SDL_SetWindowFocusable,(SDL_Window *a, SDL_bool b),(a,b),return)
+SDL_DYNAPI_PROC(float,SDL_GetAudioStreamSpeed,(SDL_AudioStream *a),(a),return)
+SDL_DYNAPI_PROC(int,SDL_SetAudioStreamSpeed,(SDL_AudioStream *a, float b),(a,b),return)