Minor tweaks to the resampler.

research/mal_resampler.h

@@ -47,7 +47,9 @@ Random Notes:
 #define MAL_RESAMPLER_SEEK_NO_CLIENT_READ   (1 << 0)    /* When set, does not read anything from the client when seeking. This does _not_ call onRead(). */
 #define MAL_RESAMPLER_SEEK_INPUT_RATE       (1 << 1)    /* When set, treats the specified frame count based on the input sample rate rather than the output sample rate. */
 
+#ifndef MAL_RESAMPLER_CACHE_SIZE_IN_BYTES
 #define MAL_RESAMPLER_CACHE_SIZE_IN_BYTES   4096
+#endif
 
 typedef struct mal_resampler mal_resampler;
 
@@ -91,7 +93,7 @@ struct mal_resampler
     {
         float     f32[MAL_RESAMPLER_CACHE_SIZE_IN_BYTES/sizeof(float)];
         mal_int16 s16[MAL_RESAMPLER_CACHE_SIZE_IN_BYTES/sizeof(mal_int16)];
-    } cache;   /* Do not use directly. Keep this as the first member of this structure for SIMD alignment purposes. */
+    } cache;   /* Keep this as the first member of this structure for SIMD alignment purposes. */
     mal_uint32 cacheStrideInFrames; /* The number of the samples between channels in the cache. The first sample for channel 0 is cacheStrideInFrames*0. The first sample for channel 1 is cacheStrideInFrames*1, etc. */
     mal_uint16 cacheLengthInFrames; /* The number of valid frames sitting in the cache, including the filter window. May be less than the cache's capacity. */
     mal_uint16 windowLength;
@@ -120,6 +122,8 @@ mal_result mal_resampler_set_rate(mal_resampler* pResampler, mal_uint32 sampleRa
 
 /*
 Dynamically adjusts the sample rate by a ratio.
+
+The ratio is in/out.
 */
 mal_result mal_resampler_set_rate_ratio(mal_resampler* pResampler, double ratio);
 
@@ -163,7 +167,7 @@ When the end of input mode is set to mal_resampler_end_of_input_mode_no_consume,
 window are not included in the calculation.
 
 This can return a negative value if nothing has yet been loaded into the internal cache. This will happen if this is called
-immediately after initialization, before the first read has been performed, and may also happen if only a few samples have
+immediately after initialization, before the first read has been performed. It may also happen if only a few samples have
 been read from the client.
 */
 double mal_resampler_get_cached_input_time(mal_resampler* pResampler);
@@ -175,9 +179,7 @@ of time in output rate making up the cached output.
 When the end of input mode is set to mal_resampler_end_of_input_mode_no_consume, the input frames currently sitting in the
 window are not included in the calculation.
 
-This can return a negative value if nothing has yet been loaded into the internal cache. This will happen if this is called
-immediately after initialization, before the first read has been performed, and may also happen if only a few samples have
-been read from the client.
+This can return a negative value. See mal_resampler_get_cached_input_time() for details.
 */
 double mal_resampler_get_cached_output_time(mal_resampler* pResampler);
 
@@ -394,7 +396,7 @@ typedef union
 
 mal_uint64 mal_resampler_read(mal_resampler* pResampler, mal_uint64 frameCount, void** ppFrames)
 {
-    mal_uint64 framesRead;
+    mal_uint64 totalFramesRead;
     mal_resampler_deinterleaved_pointers runningFramesOut;
     mal_bool32 atEnd = MAL_FALSE;
 
@@ -429,14 +431,15 @@ mal_uint64 mal_resampler_read(mal_resampler* pResampler, mal_uint64 frameCount,
     because they do not need to worry about cache reloading logic. Instead we do all of the cache reloading stuff from here.
     */
 
-    framesRead = 0;
-    while (framesRead < frameCount) {
+    totalFramesRead = 0;
+    while (totalFramesRead < frameCount) {
         double cachedOutputTime;
-        mal_uint64 framesRemaining = frameCount - framesRead;
+        mal_uint64 framesRemaining = frameCount - totalFramesRead;
         mal_uint64 framesToReadRightNow = framesRemaining;
 
         /* We need to make sure we don't read more than what's already in the buffer at a time. */
         cachedOutputTime = mal_resampler_get_cached_output_time(pResampler);
+        if (cachedOutputTime > 0) {
             if (framesRemaining > cachedOutputTime) {
                 framesToReadRightNow = (mal_uint64)floor(cachedOutputTime);
             }
@@ -493,10 +496,11 @@ mal_uint64 mal_resampler_read(mal_resampler* pResampler, mal_uint64 frameCount,
             }
 
             /* We don't want to reload the buffer if we've finished reading. */
-        framesRead += framesToReadRightNow;
-        if (framesRead == frameCount) {
+            totalFramesRead += framesToReadRightNow;
+            if (totalFramesRead == frameCount) {
                 break;
             }
+        }
 
         /*
         We need to exit if we've reached the end of the input buffer. We do not want to attempt to read more data, nor
@@ -561,7 +565,7 @@ mal_uint64 mal_resampler_read(mal_resampler* pResampler, mal_uint64 frameCount,
         }
     }
 
-    return framesRead;
+    return totalFramesRead;
 }
 
 mal_uint64 mal_resampler_seek(mal_resampler* pResampler, mal_uint64 frameCount, mal_uint32 options)