aaudio: Try to select a more-useful microphone for recording.

Fixes #13402.

Author: icculus

src/audio/aaudio/SDL_aaudio.c

@@ -65,11 +65,16 @@ static bool AAUDIO_LoadFunctions(AAUDIO_Data *data)
 {
 #define SDL_PROC(ret, func, params)                                                             \
     do {                                                                                        \
-        data->func = (ret (*) params)SDL_LoadFunction(data->handle, #func);                                     \
-        if (!data->func) {                                                                      \
+        data->func = (ret (*) params)SDL_LoadFunction(data->handle, #func);                     \
+        if (!data->func) {                                                          \
             return SDL_SetError("Couldn't load AAUDIO function %s: %s", #func, SDL_GetError()); \
         }                                                                                       \
     } while (0);
+
+#define SDL_PROC_OPTIONAL(ret, func, params)                                                          \
+    do {                                                                                              \
+        data->func = (ret (*) params)SDL_LoadFunction(data->handle, #func);  /* if it fails, okay. */ \
+    } while (0);
 #include "SDL_aaudiofuncs.h"
     return true;
 }
@@ -327,6 +332,12 @@ static bool BuildAAudioStream(SDL_AudioDevice *device)
         SDL_Log("Low latency audio disabled");
     }
 
+    if (recording && ctx.AAudioStreamBuilder_setInputPreset) {    // optional API: requires Android 28
+        // try to use a microphone that is for recording external audio. Otherwise Android might choose the mic used for talking
+        // on the telephone when held to the user's ear, which is often not useful at any distance from the device.
+        ctx.AAudioStreamBuilder_setInputPreset(builder, AAUDIO_INPUT_PRESET_CAMCORDER);
+    }
+
     LOGI("AAudio Try to open %u hz %s %u channels samples %u",
          device->spec.freq, SDL_GetAudioFormatName(device->spec.format),
          device->spec.channels, device->sample_frames);

src/audio/aaudio/SDL_aaudiofuncs.h

@@ -19,6 +19,10 @@
   3. This notice may not be removed or altered from any source distribution.
 */
 
+#ifndef SDL_PROC_OPTIONAL(ret, func, params)
+#define SDL_PROC_OPTIONAL(ret, func, params) SDL_PROC(ret, func, params)
+#endif
+
 #define SDL_PROC_UNUSED(ret, func, params)
 
 SDL_PROC(const char *, AAudio_convertResultToText, (aaudio_result_t returnCode))
@@ -35,7 +39,7 @@ SDL_PROC(void, AAudioStreamBuilder_setBufferCapacityInFrames, (AAudioStreamBuild
 SDL_PROC(void, AAudioStreamBuilder_setPerformanceMode, (AAudioStreamBuilder * builder, aaudio_performance_mode_t mode))
 SDL_PROC_UNUSED(void, AAudioStreamBuilder_setUsage, (AAudioStreamBuilder * builder, aaudio_usage_t usage))                                         // API 28
 SDL_PROC_UNUSED(void, AAudioStreamBuilder_setContentType, (AAudioStreamBuilder * builder, aaudio_content_type_t contentType))                      // API 28
-SDL_PROC_UNUSED(void, AAudioStreamBuilder_setInputPreset, (AAudioStreamBuilder * builder, aaudio_input_preset_t inputPreset))                      // API 28
+SDL_PROC_OPTIONAL(void, AAudioStreamBuilder_setInputPreset, (AAudioStreamBuilder * builder, aaudio_input_preset_t inputPreset))                      // API 28
 SDL_PROC_UNUSED(void, AAudioStreamBuilder_setAllowedCapturePolicy, (AAudioStreamBuilder * builder, aaudio_allowed_capture_policy_t capturePolicy)) // API 29
 SDL_PROC_UNUSED(void, AAudioStreamBuilder_setSessionId, (AAudioStreamBuilder * builder, aaudio_session_id_t sessionId))                            // API 28
 SDL_PROC_UNUSED(void, AAudioStreamBuilder_setPrivacySensitive, (AAudioStreamBuilder * builder, bool privacySensitive))                             // API 30
@@ -80,3 +84,4 @@ SDL_PROC_UNUSED(bool, AAudioStream_isPrivacySensitive, (AAudioStream * stream))
 
 #undef SDL_PROC
 #undef SDL_PROC_UNUSED
+#undef SDL_PROC_OPTIONAL